Zinc complexes coordinated by bipyridine-phenolate ligands as an efficient initiator for ring-opening polymerization of cyclic esters

Accepted Manuscript Zinc Complexes Coordinated by Bipyridine-Phenolate Ligands as An Efficient Initiator for Ring-Opening Polymerization of Cyclic Esters Yi-Liang Hsieh , Yi-Chien Lin , Gene-Hsiang Lee , Chi-How Peng PII:

S0032-3861(14)01100-8

DOI:

10.1016/j.polymer.2014.12.001

Reference:

JPOL 17459

To appear in:

Polymer

Received Date: 9 September 2014 Revised Date:

14 November 2014

Accepted Date: 2 December 2014

Please cite this article as: Hsieh Y-L, Lin Y-C, Lee G-H, Peng C-H, Zinc Complexes Coordinated by Bipyridine-Phenolate Ligands as An Efficient Initiator for Ring-Opening Polymerization of Cyclic Esters, Polymer (2015), doi: 10.1016/j.polymer.2014.12.001. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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For Table of Contents Use Only

Zinc Complexes Coordinated by Bipyridine-Phenolate Ligands as An Efficient Initiator for

Yi-Liang Hsieh, Yi-Chien Lin, Gene-Hsiang Lee, Chi-How Peng*

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SYNOPSIS TOC

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Ring-Opening Polymerization of Cyclic Esters

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Zinc Complexes Coordinated by BipyridinePhenolate Ligands as An Efficient Initiator for

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Ring-Opening Polymerization of Cyclic Esters

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Yi-Liang Hsieh,1 Yi-Chien Lin,1 Gene-Hsiang Lee,2 Chi-How Peng*,1

Department of chemistry and Frontier Research Center on Fundamental and Applied Sciences

of Matters, National Tsing-Hua University, Hsinchu 30013, Taiwan. Instrumentation Center, National Taiwan University, Taipei 10617, Taiwan.

ABSTRACT

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A series of zinc complexes coordinated by different bipyridine-phenolate (BpyPh) ligands, 2([2,2'-bipyridin]-6-yl)-4,6-di-tert-butylphenol (BpyPh2,4-tBu-H, 3) and 2-([2,2'-bipyridin]-6-yl)-4-

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(tert-butyl)phenol (BpyPh4-tBu-H, 4) have been synthesized. The reaction of BpyPh2,4-tBu-H with ZnEt2 gave a six-coordinated complex of [(BpyPh2,4-tBu)2Zn] (5) with the distorted octahedral geometry. However, the dinuclear complexes of [(BpyPh)Zn(µ-OBn)]2 (6 and 7) were formed when benzyl alcohol was added and then can be converted to mononuclear zinc benzylalkoxide species by the increased temperature. The ε-CL and L-LA polymerizations initiated by complex 6 showed the living characteristics of narrow molecular weight distribution (PDIs < 1.15) and the

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capability of block copolymer synthesis demonstrated by the formation of PCL-b-PVL and PCLb-PHB. The ring-opening polymerizations of cyclic esters initiated by complex 5, however, was

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not effective possibly due to the highly steric hindered metal center.

Introduction

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Poly(ε-caprolactone) (PCL) and poly(lactide) (PLA) have shown a wide application such as absorbable sutures and drug delivery in biomedical materials and pharmaceuticals due to the

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highly biocompatible and biodegradable properties.1-4 Ring-opening polymerization (ROP) is the major technique to synthesize the polyester with low polydispersity (PDI = Mw/Mn) and wellcontrolled molecular weight. Although different organometallic complexes have been utilized in ROP,5-13 zinc complexes were valued by their high activity, low cost, and negligible toxicity.14-19 However, side reactions such as backbiting and transesterification have been observed and

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resulted in the formation of macrocycles or chain redistribution, which could be largely suppressed by the sterically hindered ligands.20-21 Recently the zinc complexes coordinated by

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phenolate ligands with nitrogen donors have attracted more attention due to the well-controlled ROP mediated by zinc phenoxyimine complexes such as N,N,O-tridentate Schiff-base zinc

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alkoxides that showed a tunable steric and electronic properties for the control of ring-opening polymerization.22-31 Herein we report a relatively simple, one-pot synthesis of bulky NNO-type ligands, bipyridine-phenolate (BpyPh-H), which coordinated with zinc to form the ROP initiators that mediated the polymerization of ε-CL and L-LA with the living characters demonstrated by predictable molecular weight, narrow molecular weight distribution, and the formation of block copolymers.

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Results and Discussion Synthesis and characterization of Zn complexes

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The NNO-tridentate, bipyridine-phenolate ligands (3 and 4) were obtained through a relatively simple, one pot two steps reaction from a halogen-metal exchange of bromophenols (1 and 2) and tert-butyllithium followed by nucleophilic addition to the bipyridine.32-33 The reaction of

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BpyPh-H and ZnEt2 in toluene yielded a unique six-coordinated zinc complex with a highly sterically hindered metal center (5) but the expected product of (BpyPh)ZnEt were not obtained.

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The dinuclear Zn complexes (6 and 7), which were reported as the active species in ROP, were synthesized by the reaction of ligands and ZnEt2 with BnOH. The synthetic processes were summarized in Scheme 1 and the ligands and complexes were characterized by 1H and 13C NMR. The structures of BpyPh2,4-tBu-H (3) and [(BpyPh2,4-tBu)2Zn] (5) were further confirmed by single

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crystal X-ray crystallography (Figure 1-2).

Scheme 1. The synthesis of bipyridine-phenolate ligands (BpyPh-H) and the zinc complexes.

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The molecular structure of compound 3 showed an intramolecular hydrogen bond of O-H･･･N between the phenol and pyridine group (Figure 1). The distance of N･･･H (1.8154(16) Å) is

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substantially shorter than the Van der Waals distance of 2.75 Å for the N and H atom, and the angle (O-H･･･N(2)) formed by the hydrogen bond is 149.083(51). The structure of complex 5 revealed a monomeric Zn(II) complex that contains the Zn center with a slightly distorted

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octahedral geometry and two BpyPh2,4-tBu ligands forming a meridional isomerism (Figure 2). The angle of O-Zn-O is 89.97(14)°. The average bond distances between the Zn atom and O

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(phenoxy) and N (pyridine) are 2.012(3) and 2.187(4) Å, respectively.

Figure 1. Crystal structure of BpyPh2,4-tBu-H depicted with ellipsoids at the 50% probability.

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selected bond lengths [Å] and angles [°] for BpyPh2,4-tBu-H：O(1)-C(12) 1.3627(19), N(1)-C(1) 1.331(2), N(1)-C(5) 1.347(2), N(2)-C(6) 1.348(2), N(2)-C(10) 1.350(2).

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Figure 2. Crystal structure of [(BpyPh2,4-tBu)2Zn] depicted with ellipsoids at the 50% probability.

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selected bond lengths [Å] and angles [°] for [(BpyPh2,4-tBu)2Zn]：Zn-O(1) 1.990(3), Zn-O(2) 2.034(3), Zn-N(1) 2.161(5), Zn-N(2) 2.178(4), Zn-N(4) 2.180(4), Zn-N(3) 2.228(4), O(1)-ZnO(2) 89.97(14), O(1)-Zn-N(1) 160.11(16), O(2)-Zn-N(1) 90.75(15), O(1)-Zn-N(2) 85.76(15), O(2)-Zn-N(2) 107.74(15), N(1)-Zn-N(2) 75.10(17), O(1)-Zn-N(4) 102.95(14), O(2)-Zn-N(4)

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85.60(15), N(1)-Zn-N(4) 96.92(17), N(2)-Zn-N(4) 164.26(16), O(1)-Zn-N(3) 92.27(15), O(2)Zn-N(3) 158.72(15), N(1)-Zn-N(3) 94.23(16), N(2)-Zn-N(3) 93.53(16), N(4)-Zn-N(3) 73.28(16)

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The dinuclear complex of [(BpyPh2,4-tBu)Zn(µ-OBn)]2 (6) was mainly characterized by 1H NMR spectrum (Figure S7) and recognized by one set of doublet peaks at 3.93 and 4.81 ppm for two

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methylene protons of the benzylalkoxy groups. However, another peak at 4.63 ppm was also observed and ascribed to mononuclear zinc complex of (BpyPh2,4-tBu)ZnOBn (Figure 3a). The temperature-dependent

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H NMR spectrum demonstrated that the equilibrium between

[(BpyPh2,4-tBu)Zn(µ-OBn)]2 and (BpyPh2,4-tBu)ZnOBn gradually shifts to the mononuclear side when the temperature increased from 20oC to 50oC (Figure 3). The equilibrium constants of dinuclear/mononuclear zinc complexes transformation in different temperatures could be preliminarily estimated as 4.3×10-4 (20oC), 6.9×10-3 (30oC) and 8.3×10-3 (50oC) by the equation

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of K = [mononuclear Zn]2/[dinuclear Zn] associated with [[(BpyPh2,4-tBu)Zn(µ-OBn)]2]0 = 2.5×10-3 M. The dissociation of dinuclear zinc complex to form the mononuclear zinc complex

Ha’ (c) 50 oC

Ha

(b) 30 oC

Ha

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(a) 20 oC

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was also observed with other reported NNO-tridentate ligands.34-36

Figure 3. Temperature-dependent 1H NMR spectrum showing the change of equilibrium

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between dinuclear and mononuclear zinc complexes in CDCl3 with [[(BpyPh2,4-tBu)Zn(µ-

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OBn)]2]0 = 2.5×10-3 M at (a) 20 oC, (b) 30 oC, (c) 50 oC.

Ring-Opening Polymerization of ε-caprolactone, β-butyrolactone, and δ-valerolactone. The polymerization of ε-caprolactone was performed in toluene at varied temperature with the zinc initiators and different [ε-CL]0/[I]0 ratio (Table 1). The mononuclear zinc complex 5 led to a ROP of ε-CL to 94% monomer conversion in 24 hours at 50oC with PDI equal to 1.42 (Entry 1).

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Ring-opening polymerization of ε-caprolactone, β-butyrolactone, and δ-

Table 1.

valerolactone initiated by BpyPh coordinated Zn complexes in toluene.a Time (h) 24

Conv. (%) 94

Mnc (obsd.) 2031f

Mnd (calcd.) 5365

Mne (NMR) 5023

100

70

13

88

2149f

5022

99

1518

f

2112

f

4665

f f

1b

5

2b

5 6

4

50

6

5

50

50

6

70

100

70

12 2 2

99 99

6

200

70

2

97

9127

7

6

300

70

2

97

13483f

6

400

70

4

9

6

400

90

4

10

7

100

70

2

g

6

100

70

2

12h

6

200

70

2

h

6

200

90

1

11

13

b

TOFi

1.42

4

4043

1.77

7

2933

2946

1.31

8

2933

2962

1.12

50

5758

5870

1.09

50

11179

11065

1.11

49

16715

17685

1.15

49

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6

8

PDIc

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[ε-CL]0/[I]0

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[I]

3

a

100

Temp. (oC) 50

Entry

75

f

17230

17702

1.08

19

f

10655

86

13210

19740

19651

1.09

22

94

2420f

5472

6385

2.39

47

99

3300

4370

4410

1.04

50

99

21046

10020

9720

1.36

50

99

15037

10020

10120

1.29

99

c

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[I]0 = 5 mM. The condition ratio is [ε-CL]/[Cat.]/[BnOH] = 100/1/2. Determined by GPC and calibrated by polystyrene standards in THF. d Calculated from the molecular weight of ε-caprolactone ✕ [ε-CL]0/2[I]0 ✕ the conversion. e Obtained from 1H NMR analysis. f The values are obtained from GPC analysis multiplied by 0.56 for PCL.37 g β-butyrolactone as monomer. h δ-valerolactone as monomer. i Turnover frequency determined from the conversion and reaction time (h-1).

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Increasing the temperature from 50oC to 70oC shortened the polymerization time to 13 hours with 88% conversion but the molecular weight distribution became wider (Entry 2). The limited control efficiency of complex 5 should be attributed to the highly steric hindrance of the six coordinated zinc center. The dinuclear zinc complex 6, which has a less steric, five coordinated metal center, was also applied to ROP of ε-CL. The polymerization reached 99% conversion in 12 hours with PDI value equal to 1.31 (Entry 3). When the temperature was raised to 70oC, both

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the rate and the control of polymerization were improved. The better control efficiency was possibly due to the shifted equilibrium caused by the increased temperature to produce more mononuclear zinc complex, which is the major active catalyst. Poly(ε-caprolactone) with a

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molecular weight close to the theoretical value and a narrow molecular weight distribution was obtained in 2 hours with 99% conversion (Entry 4). Higher molecular weight of PCL could also be achieved in 2 hours with 97% conversion by increasing the [ε-CL]0/[I]0 ratio (Entry 5-7). The

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narrow molecular weight distribution and little molecular weight deviation associated with the fast polymerization rate demonstrated the high efficiency of this BpyPh2,4-tBu coordinated zinc

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initiator to mediate the ring-opening polymerization of ε-caprolactone. The polymeric products still showed a narrow molecular weight distribution when the ratio of [ε-CL]0/[I]0 was raised to 400 but the conversion approached to only 75% within 4 hours (Entry 8). The enhancement of polymerization rate became less significant when the temperature was changed from 70oC to

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90oC. The monomer conversion was just slightly increased to 86% although the molecular distribution was still narrow (Entry 9). The dinuclear zinc complex 7 that has an even less sterically hindered metal center was utilized in the ROP of ε-CL. The polymerization rate was

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similar to that with complex 6 but the higher PDI value and an obvious molecular weight deviation indicated a lower control efficiency (Entry 10), supporting the statement that sterically

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hindered ligands could suppress the side reactions. The living characters of ROP of εcaprolactone initiated by BpyPh2,4-tBu coordinated zinc complex 6 were better illustrated by a linear increased molecular weight (Mn from GPC) with ([ε-CL]0-[ε-CL])/[I]0 as well as low PDI values as shown in Figure 4. The linear first order kinetic plots (Figure 5) and the molecular weight not only increasing linearly with conversion but also matching the theoretical values (Figure 6) were also observed. The zinc complex 6 was further applied to the ROP of β-

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butyrolactone and δ-valerolactone. The polymerization of β-butyrolactone at 70oC approached

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99% conversion in 2 hours with the same control efficiency, which was judged by

Figure 4. Linear increased Mn (GPC) with the initial molar ratio of ([ε-CL]0-[ε-CL])/[I]0 (◆) and

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PDI(●) of ε-CL polymerization initiated by 6 in toluene at 70 °C.

ln([ ln([εε-CL CL]]0/[ /[εε-CL CL]]t)

4.0

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5.0

0.0

y = 6.40E-04x + 2.12E-02 R² = 9.99E-01

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3.0 2.0 1.0

0

2000

4000 6000 Time (sec)

8000

Figure 5. The first-order kinetic plots of ln([ε-CL]0/[ ε-CL]) versus time for the polymerization of ε-CL initiated by complex 6 with the condition of [ε-CL]0 / [I] 0 = 200 / 1, [ε-CL]0 = 0.5 M in toluene at 70 oC.

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Series3 M

2.4

15,000

Series1 PDI

2.2

12,000

Linear M (Series3)

2.0

n

n,theory

1.8

9,000

1.6

6,000

PDI

18,000

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Mn(GPC)

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1.4

3,000

1.2

0

1.0

20

40 60 80 Conversion (%)

100

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0

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Figure 6. The plots of Conv. vs. Mn vs. PDI for ε-CL polymerization initiated by complex 6 in toluene at 70 oC under the condition of [ε-CL]0 / [I] = 200 / 1, [ε-CL]0 = 0.5 M.

molecular weight distribution and molecular weight deviation from the theoretical values, as that of ε-caprolactone (Entry 11). Complex 6 could also initiate the ROP of δ-valerolactone with a

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similar polymerization rate, but the PDI value raised to 1.36 and the molecular weight deviation became more obvious (Entry 12). Increasing the reaction temperature to 90oC led to a faster

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polymerization of δ-valerolactone with the improved control efficiency (Entry 13).

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Ring-Opening Polymerization of L-lactide and rac-lactide The dinuclear zinc complex 6 can also efficiently control the ring-opening polymerization of Llactide at ambient temperature (Table 2). The polymerization reached almost completion in half hour with narrow molecular weight distribution when [L-LA]0/[I]0 was equal to 100 and 200 but a significant decrease in polymerization rate was observed when [L-LA]0/[I]0 increased to 300 although the molecular weight distribution was not affected (Entry 1-3). The attempt to enhance

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the polymerization rate via the elevation of temperature was not success and only trace amount of

Zn complexes in DCM.a

100

Temp. (oC) 30

Time (h) 0.5

Conv. (%) 99

Mnb (obsd.) 5379

Mnc (calcd.) 7315

Mnd (NMR) 7890

6

200

30

0.5

98

10706

14232

3

6

300

30

1

83

12632

18052

4e

6

300

50

0.5

trace

-

-

e

6

300

30

0.5

trace

-

f

6

300

50

0.5

99

7f

6

300

30

0.5

f

6

400

30

0.5

9f

6

500

30

0.5

10

7

100

30

0.5

g

11

6

200

30

0.5

12g

7

200

30

1.5

1

6

2

6

8

b

PDIb

TOFi

1.11

198

13512

1.07

196

17403

1.07

83

-

-

-

-

-

-

-

17848

21511

21080

1.13

198

98

18529

21295

19998

1.10

196

98

21640

28358

28790

1.08

196

97

24458

35059

35419

1.07

194

93

3457

6810

6882

1.11

186

99

15246

14377

14810

1.11

196

99

7576

14377

15675

1.08

66

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[L-LA]0/[I]0

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[I]

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Entry

5

a

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Table 2. Ring-opening polymerization of L-lactide and rac-lactide initiated by BpyPh coordinated

c

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[I]0 = 5 mM. Determined by GPC and calibrated by polystyrene standards in THF. Calculated from the molecular weight of L-lactide ✕ [L-LA]0/2[I]0 ✕ the conversion. d Obtained from 1H NMR analysis. e Toluene as the solvent. f DCE as the solvent. g Polymerization of rac-lactide. The heterotactic selectivity in DCM with the Pr value as 0.52 (entry 9) and 0.50 (entry 10). h The values are obtained from GPC analysis multiplied by 0.58.38-39 i Turnover frequency determined from the conversion and reaction time (h-1).

polymeric product was obtained from polymerization at 50oC in toluene (Entry 4). The

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polymerization in toluene at 30oC still produced almost no polymeric product (Entry 5) indicating that the L-LA polymerization was mainly inhibited by toluene. The 1,2-dichloroethane (DCE) was then selected as the solvent due to the similarity to dichloromethane (DCM) and the higher boiling point. Since the polymerization of L-lactide in DCE showed a narrow molecular weight distribution and high monomer conversion within half hour at both 50oC and 30oC (Entry 6 and 7), we adopted the lower temperature condition for following study. Poly(lactide) with

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higher molecular weight was obtained by increasing the monomer to initiator ratio (Entry 8-9). The molecular weight of poly(lactide) was linearly increased with ([L-LA]0-[L-LA])/[I]0 and the

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PDI values were all below 1.10 (Figure 7).

Figure 7. Linear increased Mn (GPC) with the initial molar ratio of ([L-LA]0-[L-LA])/[I]0 (◆)

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and PDI(●) of L-LA polymerization initiated by 6 in DCM/DCE at 30 °C.

The less steric hindered Zn complex 7 showed a similar control fashion as complex 6 in ROP of

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L-lactide, which was demonstrated by a 93% monomer conversion in half hour and low PDI value as 1.11 (Entry 10). The little difference between ROP of L-LA initiated by complexes 6

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and 7 suggested that the importance of bulky ligand to the suppression of side reactions became less significant in polymerization of L-lactide. Both complexes 6 and 7 could also initiate the polymerization of rac-lactide with similar polymerization behavior as that of L-lactide (entry 11 and 12), however, the Pr values were equal to 0.52 and 0.50, respectively, indicating that these NNO-tridentate Zn complexes have no heterotactic selectivity.

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Chain extension of ε-CL with β-BL and δ-VL Synthesis of block copolymer, another important feature of controlled polymerization, was

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demonstrated by the chain extension from ε-CL to β-BL and δ-VL. The living prepolymer of PCL-50 was synthesized from ROP of ε-CL initiated by complex 6 (Figure 8a, Mn = 8100, Mw/Mn = 1.08). When the monomer conversion approached to 95%, the other monomer of β-BL

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was sequentially added into the reaction to generate the block copolymer of PCL-b-PHB with Mn

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= 12200, Mw/Mn = 1.13 (Figure 8b). The polymeric product was also characterized by proton NMR spectrum (Figure 9).

(a)

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(b)

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Figure 8. GPC traces of chain extension from (a) macro-initiator of PCL, Mn=8100, Mw/Mn = 1.08, to (b) block copolymer of PCL-b-PHB, Mn=12200, PDI=1.13 with the condition of [β-

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BL]0/[I]0/[ε-CL]0=100/1/100

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e

j

g

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h

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i

f

b a

7.5

7.0

6.5

6.0

5.5

d

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8.0

c

5.0

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

ppm

Figure 9. 1H NMR spectrum of PCL(50)-b-PHB(50) in CDCl3.

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The block copolymer of PCL-b-PVL (Mn = 19600, Mw/Mn = 1.24) was obtained via a similar process from the prepolymer of PCL with Mn = 10310, Mw/Mn = 1.07 and characterized by GPC (Figure 10) and 1H NMR spectrum (Figure 11) as well. The success in block copolymerization

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indicated that the BpyPh2,4-tBu coordinated zinc complex is a versatile initiator for ring-opening

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polymerization of various cyclic esters.

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(a)

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(b)

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Figure 10. GPC traces of chain extension from (a) macro-initiator of PCL, Mn=10310, Mw/Mn = 1.07, to (b) block copolymer of PCL-b-PVL, Mn=19600, PDI=1.24 with the condition of [δ-

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VL]0/[I]0/[ε-CL]0=100/1/100.

c+d

f+j+k

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TE D

e+i

AC C

a

8.0

7.5

7.0

6.5

6.0

g

b

5.5

5.0

h

4.5

4.0

3.5

3.0

2.5

2.0

1.5

1.0

0.5

ppm

Figure 11. 1H NMR spectrum of PCL(50)-b-PVL(50) in CDCl3.

Mechanism Although all successful ROP in this work started from the dinuclear zinc complexes 6 or 7 and the cyclic esters, the proton NMR spectrum indicated that the mononuclear zinc complex is the

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major zinc species when the reaction temperature was above 30oC (Figure 3b). The polymeric products were observed to have the benzyl ester group on one end and a hydroxyl group on the other end using 1H NMR (Figure S3), suggesting a “coordination-insertion” pathway for the

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propagation process.40-45 Therefore, the mechanism of ROP initiated by [(BpyPh2,4-tBu)Zn(µOBn)]2 was proposed in scheme 2. The increased temperature drives the equilibrium of dinuclear/mononuclear zinc complexes to the mononuclear side so that the cyclic esters such as

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ε-caprolactone can coordinate to the four-coordinated, less steric zinc center. The benzylalkoxy group then attacks the activated carbonyl carbon to form the new alkoxide chain end for next

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solvent to quench the reaction.

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coordination-insertion cycle. At the end, the polyester was obtained by the addition of protic

Scheme 2. The proposed mechanism for ring-opening polymerization of ε-caprolactone initiated by dinuclear zinc complex of [(BpyPh2,4-tBu)Zn(µ-OBn)]2.

Conclusions

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A designed bipyridine-phenolate ligand, BpyPh-H, which can be simply obtained from an onepot reaction, was applied to form the zinc complexes used in ring-opening polymerization as the initiator. The six-coordinated mononuclear zinc complex 5 showed a poor initiation efficiency

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possibly due to the highly steric environment of the zinc center. The dinuclear zinc complex 6 initiated the ROP of ε-caprolactone, β-butyrolactone, δ-valerolactone, L-lactide and rac-lactide with a narrow molecular weight distribution and molecular weight close to the theoretical value

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as well as the synthesis of block copolymers, which demonstrated that this BpyPh2,4-tBu coordinated zinc complex is a versatile initiator for ROP of various cyclic esters. However, the

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temperature-dependent 1H NMR spectrum disclosed that the dinuclear zinc complex 6 gradually dissociates to mononuclear zinc complex of (BpyPh2,4-tBu)ZnOBn with an increased temperature and thus (BpyPh2,4-tBu)ZnOBn was proposed to be the actual species to initiate the ROP. Comparing to complex 6, the less steric dinuclear zinc complex 7 showed a lower control

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efficiency in the polymerization of ε-CL but performed similarly in the polymerization of L-LA, suggesting that the steric effect to suppress of side reaction is more significant in the

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polymerization of lactone.20, 46-47

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Experimental Section

Materials. Solvents were dried by refluxing at least 24 hr over sodium/benzophenone (toluene, THF, ether), CaH2 (CH2Cl2, DCE and benzyl alcohol). All cyclic ester monomers were purchased from Alfa Aesar and Aldrich. ε-Caprolactone, β-butyrolacton and δ-valerolacton were dried with CaH2 for 24 hr at room temperature and then distilled under reduced pressure. Llactide and rac-lactide were recrystallized from a toluene solution prior to use. Deuterated solvents (Aldrich) were dried over molecular sieves. Bromophenols and ZnEt2 were purchased

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from Aldrich and used without further purification. Instruments. All manipulations were carried out under a dry nitrogen atmosphere using an

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MBraun glove box and Schlenk flask. NMR spectra (400 MHz) were recorded by a Mercury-400 Spectrometer. 1H NMR chemical shifts are given in ppm versus residual protons in deuterated solvents as follows：δ 7.24 ppm (CDCl3), δ 3.58 ppm (THF-d8, O-CH2). 13

C NMR chemical

C in solvents as follows：δ 77 ppm (CDCl3). NMR

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shifts are given in ppm versus residual

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spectroscopy was used to identify the ligand structure and monomer conversion. Polymers were

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characterized by a gel permeation chromatography (GPC) system equipped with three Shodex columns (Shodex KF-802, Shodex KF-803, and Shodex KF-805) using THF eluent at 30 °C and 1.0 mL min-1 flow rate. The signal was collected by DIONEX Shodex RI-101 refractometer (RI) detector and UltiMate 3000 variable wavelength detector operated at 254 nm. The molecular weight was calibrated with narrow linear poly(styrene) Shodex standard (SM-105) ranging in

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molecular weight from 1.20 × 102 g mol-1 ~ 2.61 × 106 g mol-1. Molecular weights and the Mw/Mn value were calculated using DIONEX chromeleon software.

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Synthesis of 2-([2,2'-bipyridin]-6-yl)-4,6-di-tert-butylphenol (BpyPh2,4-tBu-H, 3)

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t-BuLi (11.6 mL, 22 mmol of a 1.9 M solution) was added dropwise to a anhydrous diethyl ether solution (20 mL) of 2-bromo-4,6-di-tert-butylphenol (2.85 g, 10 mmol) at 243 K under inert atmosphere. After one night stirring at room temperature the white suspension was slowly added to a warm solution (323 K) of 2,2-bipyridine (0.64 g, 4 mmol) in 20 mL of anhydrous toluene. Immediately, a red color was obtained. The solution was maintained at 323 K for 48 h and then cooled to 273 K and hydrolyzed slowly with H2O (30 mL). The mixture was extracted with ethyl acetate and the combined organic layers were dried over Na2SO4 for 3 h. Following filtration, 2.5

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g of MnO2 were added. The reaction mixture was stirred for 24 h at room temperature and filtered thorough Celite. The solution was evaporated to dryness with a rotary evaporator. The mixture was purified by column chromatography (silica gel, hexane/EtOAc = 6:1) to give ligand

1

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as a pale yellow oil which was recrystallized in methanol gave pale yellow solid (0.72 g, 50%). H NMR (400 MHz, CDCl3)：δ 8.71 (1H, d, J = 4 Hz, ArH), 8.31 (1H, d, J = 8 Hz, ArH), 8.23

(1H, d, J = 8 Hz, ArH), 7.98-7.90 (3H, m, ArH), 7.70 (1H, s, ArH), 7.42 (1H, s, ArH), 7.3913

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7.34(1H, m, ArH), 1.50 (9H, s, Ar-C(CH3)3), 1.36 (9H, s, Ar-C(CH3)3).

C NMR (100 MHz,

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CDCl3) ： δ158.53, 156.49, 154.78, 152.92, 149.44, 140.02, 138.60, 137.52, 137.43, 126.29, 124.08, 121.13, 120.88, 120.09, 118.91, 118.10, 35.34, 34.37, 31.62, 29.62. Mass spectrum (EI, m/z) 360.2209, calc. exact mass C24H28N2O 360.22. Anal. Calcd. (found) for C24H28N2O: N, 7.85 (7.77); C, 81.76 (79.96); H, 8.06 (7.83) %

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Synthesis of 2-([2,2'-bipyridin]-6-yl)-4-di-tert-butylphenol (BpyPh4-tBu-H, 4) n-BuLi (8.8 mL, 22 mmol of a 2.5 M solution) was added dropwise at 243 K under inert atmosphere to a anhydrous diethyl ether solution (20 mL) of 2-bromo-4-di-tert-butylphenol (2.29

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g, 10 mmol). After one night stirring at room temperature the white suspension was slowly added to a warm solution (323 K) of 2,2-bipyridine (0.64 g, 4 mmol) in 20 mL of anhydrous toluene.

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Immediately, a red color was obtained. The solution was maintained at 323 K for 48 h and then cooled to 273 K and hydrolyzed slowly with H2O (30 mL). The mixture was extracted with ethyl acetate and the combined organic layers were dried over Na2SO4 for 3 h. Following filtration, 2.5 g of MnO2 were added. The reaction mixture was stirred for 24 h at room temperature and filtered thorough Celite. The solution was evaporated to dryness with a rotary evaporator. The mixture was purified by column chromatography (silica gel, hexane/EtOAc = 6:1) to give ligand

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as a pale yellow oil which was recrystallized in methanol gave pale yellow solid (0.58 g, 48%). 1

H NMR (400 MHz, CDCl3)：δ 8.01-7.97 (2H, m, ArH), 7.87 (1H, d, J = 8 Hz, ArH), 7.81 (1H,

d, J = 4 Hz, ArH), 7.66-7.62 (2H, m, ArH) 7.24-7.23 (1H, m, ArH) 6.87 (1H, dd, J = 8.8, 2.8 Hz,

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ArH) 6.81-6.78(1H, m, ArH), 6.14 (1H, d, J = 8 Hz, ArH), 1.27 (9H, s, Ar-C(CH3)3). 13C NMR (100 MHz, CDCl3)：δ 157.70, 157.32, 154.68, 153.35, 149.56, 141.50, 138.72, 137.32, 129.02, 124.17, 122.80, 120.79, 119.26, 119.24, 118.08, 117.94, 34.20, 31.56. Mass spectrum (EI, m/z)

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304.1571, calc. exact mass C20H20N2O 304.16. Anal. Calcd. (found) for C20H20N2O: N, 9.25

Synthesis of [(BpyPh2,4-tBu)2Zn] (5)

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(9.20); C, 81.16 (78.92); 6.82 (6.62) %

To an ice cold solution (0 oC) of BpyPh2,4-tBu-H (0.36 g, 1 mmol) in toluene (5 mL) was slowly added ZnEt2 (0.5 mL, 0.5 mmol). The mixture was stirred at room temperature overnight, and the

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resulting precipitate was collected by filtration. The precipitate was washed with pentane twice, then dried under vacuum to give yellow powder (0.30 g, 78%). 1H NMR (400 MHz, CDCl3) δ 7.98-7.92 (2H. m, ArH), 7.83-7.80 (2H, m, ArH), 7.69-7.66 (2H, m, ArH), 7.20 (1H, d, J = 4 Hz,

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ArH), 7.05 (1H, d, J = 2.8 Hz, ArH), 6.97-6.94 (1H, m, ArH), 1.25 (9H, s, Ar-C(CH3)3), 0.88 (9H, s, Ar-C(CH3)3).

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C NMR (100 MHz, CDCl3)：δ 166.66, 164.64, 151.09, 148.75, 147.18,

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140.57, 138.22, 137.89, 132.18, 125.60, 125.56, 124.30, 124.20, 120.90, 120.42, 115.69, 35.09, 33.86, 31.63, 29.11. Mass spectrum (FAB, m/z) 782.3533, calc. exact mass C48H54N4O2Zn 782.35. Anal. Calcd. (found) for C48H54N4O2Zn: N, 6.92 (7.14); C, 72.54 (73.50); H, 6.96 (6.94) % Synthesis of [(BpyPh2,4-tBu)Zn(µ-OBn)]2 (6)

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ZnEt2 (0.5 mL, 1.0 M in hexane, 0.5 mmol) was added to a solution of benzyl alcohol (0.1 mL, 1 mmol) in toluene (2.5 mL). The mixture was stirred for 3 h at room temperature and then dried in a vacuum. The mixture was cooled to 0 oC and then a solution of ligand BpyPh2,4-tBu-H (0.18 g,

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0.5 mmol) in 4 mL toluene was added slowly and stirred overnight. The resulting precipitate was collected by filtration and dried under a vacuum to give yellow powder (0.22 g, 82%). 1H NMR (400 MHz, CDCl3) δ 7.96-7.92 (4H. m, ArH), 7.82 (2H, d, J = 8 Hz, ArH), 7.74-7.71 (6H. m,

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ArH), 7.51 (2H, d, J = 2.4 Hz, ArH), 7.33 (2H, d, J = 2.4 Hz, ArH), 6.94 (10H, s, Ph), 6.76-6.73 (2H. m, ArH), 4.81 (2H, d, J = 12 Hz, CHHPh), 3.93 (2H, d, J = 12 Hz, CHHPh), 1.47(18H, s,

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Ar-C(CH3)3), 1.10 (18H, s, Ar-C(CH3)3). FAB-MS : m/z 865.4 ([M − 2 CH2Ph − O]+, 20), 423.3 ([LZn]+, 100), Anal. Calcd. (found) for C62H68N4O4Zn2: N, 4.70 (5.27); C, 71.24 (69.99); H, 6.66 (6.44) %

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Synthesis of [(BpyPh4-tBu)Zn(µ-OBn)]2 (7)

ZnEt2 (0.5 mL, 1.0 M in hexane, 0.5 mmol) was added to a solution of benzyl alcohol (0.1 mL, 1 mmol) in toluene (2.5 mL). The mixture was stirred for 3 h at room temperature and then dried in

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a vacuum. The mixture was cooled to 0 oC and then a solution of ligand BpyPh4-tBu-H (0.15 g, 0.5 mmol) in 4 mL toluene was added slowly and stirred overnight. The resulting precipitate was

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collected by filtration and dried under a vacuum to give yellow powder (0.20 g, 86%). 1H NMR (400 MHz, THF-d8) δ 8.71 (2H, d, J = 8 Hz, ArH), 8.41 (2H, d, J = 8 Hz, ArH), 8.21 (2H, d, J = 8 Hz, ArH), 8.14 (2H, d, J = 8 Hz, ArH), 8.04 (2H, t, J = 8 Hz, ArH), 7.93 (4H, d, J = 2 Hz, ArH), 7.42 (4H. m, ArH), 7.31 (8H, m, ArH), 7.16 (2H, d, J = 8 Hz, ArH), 6.91 (2H, d, J = 8 Hz, ArH), 4.54 (4H, s, CH2Ph), 1.37 (18H, s, Ar-C(CH3)3). FAB-MS : m/z 753.3 ([M − 2 CH2Ph − O]+, 2.5), 367.2 ([LZn]+, 100). Anal. Calcd. (found) for C54H52N4O4Zn2: N, 5.73 (5.89); C, 64.95 (68.14); H, 5.43 (5.51) %

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Typical procedure for ROP of ε-caprolactone initiated by complex 6 A solution of complex 6 (0.053 g, 0.05 mmol) in toluene (10 mL), ε-caprolactone (0.55 mL, 5.0

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mmol) was added and the reaction mixture was stirred at 70 oC for 2 hr. The conversion yield (99%) of PCL was analyzed by 1H NMR spectroscopic studies. After the reaction was quenched by the addition of acetic acid, the polymer was precipitated into hexane. The white solid was

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dissolved in CH2Cl2 (10.0 mL) and then hexane (100.0 mL) was added for recrystallization and was then evaporated to dryness under vacuum to yield a white solid.

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Typical procedure for ROP of L-lactide initiated by complex 6

A solution of complex 6 (0.026 g, 0.025 mmol) and L-lactide (0.36 mg, 2.5 mmol) in DCM (5 mL). The reaction mixture was stirred at 30 oC for 30 min. The conversion yield (99%) of PLLA was analyzed by 1H NMR spectroscopic studies. After the reaction was quenched by the addition

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of acetic acid, the polymer was precipitated into hexane. The white solid was dissolved in CH2Cl2 (10.0 mL) and then hexane (100.0 mL) was added for recrystallization and was then

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evaporated to dryness under vacuum to yield a white solid. Synthesis of PCL-b-PVL and PCL-b-PHB diblock copolymers initiated by complex 6

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The polymerization procedures were exemplified by the synthesis of PCL(50)-b-PVL(50) and PCL(50)-b-PHB(50) (the number 50 indicates the [ε-CL]0/2[I]0, [δ-VL]0/2[I]0 and [β-BL]0/2[I]0 ratio). The macroinitiator of PCL-50 was synthesized by the approach described in previous paragraph. After 2h polymerization of ε-CL, the conversion reached more than 95% and then δVL (5.0 mmol) or β-BL (5.0 mmol) was added. The reaction mixture was stirred for another 2 h in 90 oC for δ-VL or 3 h in 70 oC for β-BL and then was quenched using the procedures described previously.

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ASSOCIATED CONTENT Supporting Information: GPC traces of ε-CL and L-LA polymerization, NMR spectrum of the all compound, FAB mass spectrum of complexes 6 and 7 and the crystallographic data of

Corresponding Author

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ACKNOWLEDGMENT

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*E-mail: [email protected]

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AUTHOR INFORMATION

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compound 3 and complex 5.

This work was supported by the National Science Council in Taiwan (NSC 102-2113-M-007-

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007-MY2).

REFERENCES

1. Jeong, B.; Bae, Y. H.; Lee, D. S.; Kim, S. W., Nature 1997, 388, 860-862. 2. Drumright, R. E.; Gruber, P. R.; Henton, D. E., Adv. Mater. 2000, 12, 1841-1846. 3. Gross, R. A.; Kalra, B., Science 2002, 297, 803-807. 4. Li, Y. Y.; Cunin, F.; Link, J. R.; Gao, T.; Betts, R. E.; Reiver, S. H.; Chin, V.; Bhatia, S. N.; Sailor, M. J., Science 2003, 299, 2045-2047.

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5. O'Keefe, B. J.; Hillmyer, M. A.; Tolman, W. B., J. Chem. Soc., Dalton Trans. 2001, 30, 2215-2224. 6. Dechy-Cabaret, O.; Martin-Vaca, B.; Bourissou, D., Chem. Rev. 2004, 104, 6147-6176. 7. Wu, J.; Yu, T. L.; Chen, C. T.; Lin, C. C., Coord. Chem. Rev. 2006, 250, 602-626. 8. Platel, R. H.; Hodgson, L. M.; Williams, C. K., Polym. Rev. 2008, 48, 11-63. 9. Ajellal, N.; Carpentier, J. F.; Guillaume, C.; Guillaume, S. M.; Helou, M.; Poirier, V.; Sarazin, Y.; Trifonov, A., Dalton Trans. 2010, 39, 8363-8376. 10. Chisholm, M. H., Pure Appl. Chem. 2010, 82, 1647-1662. 11. Thomas, C. M., Chem. Soc. Rev. 2010, 39, 165-173. 12. Wang, Y.; Liu, B.; Wang, X.; Zhao, W.; Liu, D.; Liu, X.; Cui, D., Polym. Chem. 2014, 5, 4580-4588. 13. Yi, W.; Ma, H., Dalton Trans. 2014, 43, 5200-5210. 14. Cheng, M.; Attygalle, A. B.; Lobkovsky, E. B.; Coates, G. W., J. Am. Chem. Soc. 1999, 121, 11583-11584. 15. Chamberlain, B. M.; Cheng, M.; Moore, D. R.; Ovitt, T. M.; Lobkovsky, E. B.; Coates, G. W., J. Am. Chem. Soc. 2001, 123, 3229-3238. 16. Chisholm, M. H.; Gallucci, J.; Phomphrai, K., Inorg. Chem. 2002, 41, 2785-2794. 17. Williams, C. K., Chem. Soc. Rev. 2007, 36, 1573-1580. 18. Wheaton, C. A.; Hayes, P. G.; Ireland, B. J., Dalton Trans. 2009, 38, 4832-4846. 19. Mou, Z.; Liu, B.; Wang, M.; Xie, H.; Li, P.; Li, L.; Li, S.; Cui, D., Chem. Commun. 2014, 50, 11411-11414. 20. Huang, B. H.; Lin, C. N.; Hsueh, M. L.; Athar, T.; Lin, C. C., Polymer 2006, 47, 66226629. 21. Chuang, H. J.; Weng, S. F.; Chang, C. C.; Lin, C. C.; Chen, H. Y., Dalton Trans. 2011, 40, 9601-9607. 22. Williams, C. K.; Breyfogle, L. E.; Choi, S. K.; Nam, W.; Young, V. G.; Hillmyer, M. A.; Tolman, W. B., J. Am. Chem. Soc. 2003, 125, 11350-11359. 23. Zheng, Z.; Zhao, G.; Fablet, R.; Bouyahyi, M.; Thomas, C. M.; Roisnel, T.; Casagrande Jr, O.; Carpentier, J.-F., New J. Chem. 2008, 32, 2279-2291. 24. Huang, Y.; Hung, W. C.; Liao, M. Y.; Tsai, T. E.; Peng, Y. L.; Lin, C. C., J. Polym. Sci. Part A: Polym. Chem. 2009, 47, 2318-2329. 25. Darensbourg, D. J.; Karroonnirun, O., Inorg. Chem. 2010, 49, 2360-2371. 26. Piedra-Arroni, E.; Brignou, P.; Amgoune, A.; Guillaume, S. M.; Carpentier, J. F.; Bourissou, D., Chem. Comm. 2011, 47, 9828-9830. 27. Roberts, C. C.; Barnett, B. R.; Green, D. B.; Fritsch, J. M., Organometallics 2012, 31, 4133-4141. 28. Sung, C. Y.; Li, C. Y.; Su, J. K.; Chen, T. Y.; Lin, C. H.; Ko, B. T., Dalton Trans. 2012, 41, 953-961. 29. Chuang, H. J.; Chen, H. L.; Huang, B. H.; Tsai, T. E.; Huang, P. L.; Liao, T. T.; Lin, C. C., J. Polym. Sci. Part A: Polym. Chem. 2013, 51, 1185-1196. 30. Rezayee, N. M.; Gerling, K. A.; Rheingold, A. L.; Fritsch, J. M., Dalton Trans. 2013, 42, 5573. 31. Yu, X. F.; Zhang, C.; Wang, Z. X., Organometallics 2013, 32, 3262-3268. 32. Gebbink, R. J. K.; Watanabe, M.; Pratt, R. C.; Stack, T. D. P., Chem. Comm. 2003, 630631. 33. Arora, H.; Philouze, C.; Jarjayes, O.; Thomas, F., Dalton Trans. 2010, 39, 10088-10098.

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Zinc Complexes Coordinated by Bipyridine-Phenolate Ligands as An Efficient

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Initiator for Ring-Opening Polymerization of Cyclic Esters Yi-Liang Hsieh, Yi-Chien Lin, Gene-Hsiang Lee, Chi-How Peng*

Designed ligands were obtained via a simple, one pot synthetic process




Well controlled ring-opening polymerization of various cyclic esters was achieved




Different block copolymers of lactones have been synthesized

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Zinc Complexes Coordinated by Bipyridine-Phenolate Ligands as An Efficient Initiator for Ring-Opening

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Polymerization of Cyclic Esters

Yi-Liang Hsieh, 1 Yi-Chien Lin, 1 Gene-Hsiang Lee, 2 Chi-How Peng*,1 1

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Department of chemistry and Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing-Hua University, Hsinchu 30013, Taiwan. 2 Instrumentation Center, National Taiwan University, Taipei 10617, Taiwan.

Contents A.

Gel permeation chromatographic studies of PCL and PLLA .............................. 2

B.

1

C.

FAB mass spectrum of complexes 6 and 7 ............................................................. 8

H and 13C NMR spectrum .................................................................................... 3

D. Summary of Crystallographic Data .................................................................... 10

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Figure S1 GPC traces of PCL produced by ROP of -caprolactone with complex 6. In Table 1, the conditions are [-CL]0 : [I]0 = 50 : 1 (Entry 4, PDI = 1.12, Mn = 2112), [CL]0 : [I]0 = 100 : 1 (Entry 5, PDI = 1.09, Mn = 4665), [-CL]0 : [I]0 = 200 : 1 (Entry 6, PDI = 1.11, Mn = 9127) and [-CL]0 : [I]0 = 300 : 1 (Entry 7, PDI = 1.15, Mn = 13483). All the -CL polymerizations were carried out in toluene at 70 °C.

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Figure S2 GPC traces of PCL produced by ROP of L-lactide with complex 6. In Table 2, the conditions are [L-LA]0 : [I]0 = 100 : 1 (Entry 1, PDI = 1.11, Mn = 5379), [L-LA]0 : [I]0 = 200 : 1 (Entry 2, PDI = 1.07, Mn = 10706), [L-LA]0 : [I]0 = 300 : 1 (Entry 5, PDI = 1.10, Mn = 18529), [L-LA]0 : [I]0 = 400 : 1 (Entry 6, PDI = 1.08, Mn = 21640) and [LLA]0 : [I]0 = 500 : 1 (Entry 7, PDI = 1.07, Mn = 24458). The L-LA polymerizations were carried out in DCM or DCE at 30 °C. 2

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Figure S3 1H NMR spectrum of the polyesters of (a) PCL-100 and (b) PLLA-100. 3

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Figure S4 (a) 1H NMR and (b) 13C NMR spectrum of 2-([2,2'-bipyridin]-6-yl)-4,6-ditert-butylphenol (BpyPh2,4-tBu-H, 3).

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Figure S5 (a) 1H NMR and (b) 13C NMR spectrum of 2-([2,2'-bipyridin]-6-yl)-4-ditert-butylphenol (BpyPh4-tBu-H, 4).

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Figure S6 (a) 1H NMR and (b) 13C NMR spectrum of (BpyPh2,4-tBu)2Zn (5).

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Figure S7 1H NMR spectrum of (a) [(BpyPh2,4-tBu)Zn(μ-OBn)]2 (6) and (b) [(BpyPh4tBu )Zn(μ-OBn)]2 (7).

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Figure S8 FAB mass spectrum of [(BpyPh2,4-tBu)Zn(μ-OBn)]2 (6) using 3-Nitrobenzyl alcohol (3NBA) as matrix.

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Figure S9 FAB mass spectrum of [(BpyPh4-tBu)Zn(μ-OBn)]2 (7) using 3-Nitrobenzyl alcohol (3NBA) as matrix.

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C24H28N2O

C50H60Cl2N4O3Zn

formula weight

360.48

901.29

color

Yellow

empirical formula

Monoclinic

crystal system space group

P2(1)/c 21.3528(6)

b (Å )

5.9391(2)

c (Å )

Orthorhombic Pbca

17.2028(9) 17.0843(8)

16.0490(5)

31.6397(15)







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4

8

2034.18(11)

9298.8(8)

1.177

1.288

0.072

0.689

150(2)

150(2)

range (deg)

1.91 to 25.00

1.29 to 25.00

reflns collect.

12656

31236

indpndnt reflns

3544

8191

0.0421

0.0704

wR2

0.1016

0.1240

GOF

1.011

1.065

(deg) (deg)

Z V(Å 3) Dcalc(g/cm3)

AC C

temp (K)

EP

(Mo K)(mm-1)

TE D

(deg)

a

R1

b c

a

Yellow

M AN U

a (Å )

RI PT

3

SC

Compound

R1=|(|Fo|-|Fc|)/|Fo||. bwR2={[w(Fo2-Fc2)2]/[w](Fo2)2}1/2 cGOF=[w(Fo2-Fc2)2]/(Nrflns-Nparams)]1/2.

10

ACCEPTED MANUSCRIPT

Identification code

ic16037

Empirical formula

C24 H28 N2 O

Formula weight

360.48

Temperature

150(2) K

Wavelength

0.71073 Å

Crystal system

Monoclinic

Space group

P2(1)/c

Unit cell dimensions

a = 21.3528(6) Å b = 5.9391(2) Å c = 16.0490(5) Å 2034.18(11) Å 3

Z

4

Density (calculated)

1.177 Mg/m3

= 90°.

= 91.8834(16)°.  = 90°.

M AN U

SC

Volume

RI PT

Table S2. Crystal data and structure refinement for compound 3.

0.072 mm-1

Absorption coefficient F(000)

776

0.50 x 0.15 x 0.04 mm3

Crystal size Theta range for data collection Index ranges

1.91 to 25.00°.

-25<=h<=25, -7<=k<=7, -19<=l<=18

Independent reflections

12656

TE D

Reflections collected

3544 [R(int) = 0.0423]

Completeness to theta = 25.00°

99.2 %

Absorption correction

Semi-empirical from equivalents 0.998 and 0.952

Refinement method

Full-matrix least-squares on F2

EP

Max. and min. transmission

3544 / 0 / 251

Goodness-of-fit on F2

1.011

Final R indices [I>2sigma(I)]

R1 = 0.0421, wR2 = 0.1016

R indices (all data)

R1 = 0.0805, wR2 = 0.1152

Largest diff. peak and hole

0.175 and -0.209 e.Å -3

AC C

Data / restraints / parameters

11

ACCEPTED MANUSCRIPT Table S3. Atomic coordinates for compound 3.

( x 104) and equivalent

isotropic displacement parameters (Å 2x 103)

the trace of the orthogonalized U ij tensor.

U(eq) is defined as one third of

________________________________________________________________________________ x

y

z

U(eq)

1855(1)

3433(2)

2465(1)

35(1)

N(1)

-420(1)

6048(2)

1100(1)

36(1)

N(2)

1253(1)

5458(2)

1269(1)

30(1)

C(1)

-936(1)

4996(3)

1333(1)

44(1)

C(2)

-945(1)

2853(3)

1662(1)

40(1)

C(3)

-387(1)

1716(3)

1757(1)

37(1)

C(4)

159(1)

2773(3)

1537(1)

32(1)

C(5)

128(1)

4941(3)

1210(1)

29(1)

C(6)

692(1)

6202(3)

972(1)

28(1)

C(7)

644(1)

C(8)

1175(1)

C(9)

1748(1)

C(10)

1780(1)

C(11)

2381(1)

C(12)

2396(1)

C(13)

SC

RI PT

O(1)

M AN U

________________________________________________________________________________

477(1)

34(1)

9299(3)

307(1)

38(1)

8583(3)

629(1)

36(1)

6601(3)

1101(1)

30(1)

5752(3)

1473(1)

29(1)

4288(3)

2166(1)

28(1)

2968(1)

3729(3)

2578(1)

27(1)

3512(1)

4558(3)

2242(1)

29(1)

3523(1)

5925(3)

1531(1)

29(1)

2952(1)

6491(3)

1164(1)

31(1)

2982(1)

2291(3)

3376(1)

30(1)

2602(1)

3452(3)

4054(1)

36(1)

2719(1)

-70(3)

3194(1)

38(1)

3651(1)

1999(3)

3742(1)

38(1)

C(21)

4152(1)

6747(3)

1212(1)

31(1)

C(22)

4569(1)

4722(3)

1009(1)

37(1)

C(23)

4486(1)

8171(3)

1893(1)

43(1)

C(24)

4076(1)

8217(3)

432(1)

38(1)

C(15) C(16) C(17) C(18) C(19)

AC C

C(20)

EP

C(14)

TE D

8107(3)

________________________________________________________________________________

12

ACCEPTED MANUSCRIPT Table S4. Bond lengths [Å ] and angles [°] for compound 3. _____________________________________________________ 1.3627(19)

N(1)-C(1)

1.331(2)

N(1)-C(5)

1.347(2)

N(2)-C(6)

1.348(2)

N(2)-C(10)

1.350(2)

C(1)-C(2)

1.378(3)

C(2)-C(3)

1.374(2)

C(3)-C(4)

1.379(2)

C(4)-C(5)

1.391(2)

C(5)-C(6)

1.480(2)

C(6)-C(7)

1.385(2)

C(7)-C(8)

1.373(2)

C(8)-C(9)

1.378(2)

C(9)-C(10)

1.400(2)

C(10)-C(11)

1.484(2)

C(11)-C(16)

1.402(2)

C(11)-C(12)

1.411(2)

C(12)-C(13)

1.410(2)

C(13)-C(14)

1.388(2)

C(15)-C(16) C(15)-C(21) C(17)-C(19) C(17)-C(20)

SC M AN U

1.401(2) 1.378(2) 1.533(2)

AC C

C(17)-C(18)

TE D

C(14)-C(15)

1.539(2)

EP

C(13)-C(17)

RI PT

O(1)-C(12)

1.535(2) 1.537(2) 1.540(2)

C(21)-C(24)

1.531(2)

C(21)-C(22)

1.537(2)

C(21)-C(23)

1.538(2)

C(1)-N(1)-C(5)

117.19(16)

C(6)-N(2)-C(10)

120.14(15)

N(1)-C(1)-C(2)

124.26(18)

C(3)-C(2)-C(1)

118.25(18)

C(2)-C(3)-C(4)

118.99(18)

C(3)-C(4)-C(5)

119.19(17)

13

115.46(15)

C(4)-C(5)-C(6)

122.45(16)

N(2)-C(6)-C(7)

121.28(16)

N(2)-C(6)-C(5)

117.69(15)

C(7)-C(6)-C(5)

121.02(15)

C(8)-C(7)-C(6)

119.25(16)

C(7)-C(8)-C(9)

119.68(17)

C(8)-C(9)-C(10)

119.36(17)

N(2)-C(10)-C(9)

120.22(15)

N(2)-C(10)-C(11)

117.67(15)

C(9)-C(10)-C(11)

122.02(16)

C(16)-C(11)-C(12)

118.30(15)

C(16)-C(11)-C(10)

120.09(16)

C(12)-C(11)-C(10)

121.53(15)

O(1)-C(12)-C(11)

120.63(14)

O(1)-C(12)-C(13)

118.54(15)

C(11)-C(12)-C(13)

120.80(15)

C(14)-C(13)-C(12)

117.22(15)

C(14)-C(13)-C(17)

121.81(14)

C(12)-C(13)-C(17)

120.96(15)

C(13)-C(14)-C(15) C(16)-C(15)-C(14) C(16)-C(15)-C(21)

123.98(15) 116.81(15) 123.53(15) 119.65(14)

EP

C(14)-C(15)-C(21)

SC

N(1)-C(5)-C(6)

M AN U

122.09(16)

TE D

N(1)-C(5)-C(4)

RI PT

ACCEPTED MANUSCRIPT

122.70(16)

C(19)-C(17)-C(20)

107.42(14)

C(19)-C(17)-C(13)

110.59(14)

C(20)-C(17)-C(13)

111.89(14)

C(19)-C(17)-C(18)

110.25(14)

C(20)-C(17)-C(18)

106.56(14)

C(13)-C(17)-C(18)

110.03(13)

C(24)-C(21)-C(15)

112.57(14)

C(24)-C(21)-C(22)

108.63(14)

C(15)-C(21)-C(22)

109.96(14)

C(24)-C(21)-C(23)

107.56(15)

C(15)-C(21)-C(23)

109.22(14)

C(22)-C(21)-C(23)

108.81(14)

AC C

C(15)-C(16)-C(11)

14

ACCEPTED MANUSCRIPT _____________________________________________________________

AC C

EP

TE D

M AN U

SC

RI PT

Symmetry transformations used to generate equivalent atoms:

15

ACCEPTED MANUSCRIPT Table S5. Anisotropic displacement parameters (Å 2x 103) for compound 3. The anisotropic displacement factor exponent takes the form: -22[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______________________________________________________________________________ U11

U22

U33

U23

U13

U12

______________________________________________________________________________ 25(1)

42(1)

39(1)

12(1)

0(1)

1(1)

N(1)

27(1)

35(1)

46(1)

1(1)

3(1)

3(1)

N(2)

28(1)

31(1)

30(1)

0(1)

-1(1)

2(1)

C(1)

32(1)

44(1)

56(1)

1(1)

5(1)

3(1)

C(2)

37(1)

43(1)

41(1)

2(1)

7(1)

-7(1)

C(3)

44(1)

34(1)

32(1)

1(1)

-2(1)

-2(1)

C(4)

32(1)

34(1)

31(1)

-2(1)

-4(1)

3(1)

C(5)

31(1)

31(1)

26(1)

-2(1)

-1(1)

2(1)

C(6)

28(1)

30(1)

27(1)

-3(1)

-1(1)

4(1)

C(7)

30(1)

38(1)

34(1)

4(1)

-2(1)

6(1)

C(8)

37(1)

39(1)

38(1)

11(1)

0(1)

4(1)

C(9)

33(1)

38(1)

39(1)

10(1)

4(1)

-2(1)

C(10)

29(1)

33(1)

28(1)

0(1)

2(1)

-1(1)

C(11)

30(1)

30(1)

28(1)

0(1)

0(1)

0(1)

C(12)

26(1)

29(1)

29(1)

-1(1)

5(1)

-2(1)

C(13)

28(1)

27(1)

25(1)

-2(1)

0(1)

3(1)

C(14)

28(1)

31(1)

28(1)

-2(1)

-2(1)

3(1)

C(15)

28(1)

30(1)

27(1)

-2(1)

0(1)

0(1)

C(16)

33(1)

33(1)

26(1)

3(1)

2(1)

-2(1)

C(17)

31(1)

29(1)

29(1)

2(1)

2(1)

3(1)

C(18)

43(1)

36(1)

30(1)

3(1)

3(1)

3(1)

C(19)

43(1)

31(1)

40(1)

4(1)

3(1)

4(1)

C(20)

37(1)

44(1)

33(1)

7(1)

-2(1)

5(1)

C(21)

27(1)

36(1)

31(1)

-1(1)

2(1)

-4(1)

C(22)

33(1)

43(1)

35(1)

-1(1)

4(1)

-1(1)

C(23)

40(1)

49(1)

41(1)

-6(1)

1(1)

-11(1)

C(24)

34(1)

40(1)

40(1)

5(1)

4(1)

-5(1)

SC

M AN U

TE D

EP

AC C

RI PT

O(1)

______________________________________________________________________________

16

ACCEPTED MANUSCRIPT Table S6. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å 2x 10 3) for compound 3. ________________________________________________________________________________ x

y

z

U(eq)

________________________________________________________________________________

3820

2151

53

H(1A)

-1323

5774

1269

H(2)

-1327

2179

1819

H(3)

-377

224

1971

H(4)

551

2029

1608

H(7)

247

8583

257

41

H(8)

1149

10610

-31

46

H(9)

2116

9426

532

44

H(14)

3901

H(16)

2945

H(18A)

2793

H(18B)

2601

H(18C)

2170

H(19A)

2293

H(19B)

SC

RI PT

1551

M AN U

H(1)

52 48 44 39

2510

35

7421

682

37

4909

4195

55

2500

4552

55

3687

3845

55

58

2952

57

2709

-933

3714

57

2986

-843

2801

57

3906

1195

3342

57

3639

1134

4262

57

3835

3483

3857

57

4971

5261

811

55

4361

3805

575

55

4640

3810

1512

55

H(23A)

4895

8657

1699

65

H(23B)

4545

7268

2400

65

H(23C)

4231

9496

2013

65

H(24A)

3825

9547

559

57

H(24B)

3864

7352

-15

57

H(24C)

4489

8694

252

57

H(20A) H(20B) H(20C) H(22A) H(22B)

AC C

H(22C)

EP

H(19C)

TE D

4175

________________________________________________________________________________

17

ACCEPTED MANUSCRIPT Table S7. Hydrogen bonds for compound 3 [Å and °]. ____________________________________________________________________________ D-H...A

d(D-H)

d(H...A)

d(D...A)

<(DHA)

____________________________________________________________________________ O(1)-H(1)...N(2)

0.84

1.82

2.5727(17)

149.1

AC C

EP

TE D

M AN U

SC

RI PT

____________________________________________________________________________ Symmetry transformations used to generate equivalent atoms:

18

ACCEPTED MANUSCRIPT Table S8. Crystal data and structure refinement for complex 5. ic16203

Empirical formula

C50 H60 Cl2 N4 O3 Zn

Formula weight

901.29

Temperature

150(2) K

Wavelength

0.71073 Å

Crystal system

Orthorhombic

Space group

Pbca

Unit cell dimensions

a = 17.2028(9) Å b = 17.0843(8) Å c = 31.6397(15) Å 9298.8(8) Å 3

Z

8

Density (calculated)

1.288 Mg/m3

= 90°. = 90°.

 = 90°.

M AN U

SC

Volume

RI PT

Identification code

0.689 mm-1

Absorption coefficient F(000)

3808

0.50 x 0.11 x 0.04 mm3

Crystal size Theta range for data collection Index ranges

1.29 to 25.00°.

-20<=h<=20, -20<=k<=20, -37<=l<=0

Independent reflections

31236

TE D

Reflections collected

8191 [R(int) = 0.1434]

Completeness to theta = 25.00°

100.0 %

Absorption correction

Semi-empirical from equivalents 0.9730 and 0.7246

Refinement method

Full-matrix least-squares on F2

EP

Max. and min. transmission

8191 / 2 / 551

Goodness-of-fit on F2

1.065

Final R indices [I>2sigma(I)]

R1 = 0.0704, wR2 = 0.1240

R indices (all data)

R1 = 0.1447, wR2 = 0.1435

Extinction coefficient

0.00080(6)

Largest diff. peak and hole

0.987 and -0.599 e.Å -3

AC C

Data / restraints / parameters

19

ACCEPTED MANUSCRIPT Table S9. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å 2x 103) for complex 5. U(eq) is defined as one third of

the trace of the orthogonalized Uij tensor.

________________________________________________________________________________ x

y

z

U(eq)

6234(1)

6429(1)

1981(1)

21(1)

O(1)

6646(2)

6217(2)

2557(1)

21(1)

O(2)

7174(2)

5886(2)

1724(1)

21(1)

N(1)

6009(3)

7027(3)

1391(2)

27(1)

N(2)

6550(2)

7643(2)

2100(1)

21(1)

N(3)

5026(3)

6582(3)

2222(1)

24(1)

N(4)

5606(2)

5356(2)

1830(1)

18(1)

C(1)

5724(4)

6676(4)

1041(2)

34(2)

C(2)

5697(4)

7036(4)

652(2)

47(2)

C(3)

5972(5)

C(4)

6267(4)

C(5)

6293(3)

C(6)

6624(3)

C(7)

7001(3)

C(8)

7333(3)

C(9)

SC

RI PT

Zn

M AN U

________________________________________________________________________________

619(2)

61(2)

8148(4)

975(2)

51(2)

7759(3)

1358(2)

26(1)

8093(3)

1749(2)

25(2)

8812(3)

1750(2)

28(2)

9071(3)

2122(2)

31(2)

7255(3)

8622(3)

2480(2)

28(2)

6834(3)

7916(3)

2471(2)

21(1)

6659(3)

7494(3)

2872(2)

19(1)

6567(3)

6673(3)

2889(2)

21(1)

6412(3)

6330(3)

3299(2)

21(1)

6339(3)

6806(3)

3644(2)

23(1)

6424(3)

7634(3)

3627(2)

23(1)

6594(3)

7946(3)

3239(2)

23(1)

C(17)

6371(3)

5440(3)

3351(2)

23(1)

C(18)

7174(3)

5091(3)

3245(2)

35(2)

C(19)

6170(4)

5186(3)

3806(2)

37(2)

C(20)

5759(3)

5068(3)

3059(2)

35(2)

C(21)

6320(4)

8119(3)

4037(2)

29(2)

C(22)

5523(4)

7956(4)

4228(2)

42(2)

C(23)

6398(4)

9002(3)

3962(2)

46(2)

C(24)

6938(4)

7879(4)

4364(2)

45(2)

C(25)

4702(3)

7250(3)

2367(2)

28(2)

C(26)

3968(3)

7287(4)

2542(2)

36(2)

C(11) C(12) C(13) C(14) C(15)

AC C

C(16)

EP

C(10)

TE D

7784(4)

20

3538(3)

6603(4)

2569(2)

32(2)

C(28)

3858(3)

5910(3)

2424(2)

30(2)

C(29)

4599(3)

5913(3)

2256(2)

21(1)

C(30)

4980(3)

5212(3)

2071(2)

19(1)

C(31)

4689(3)

4462(3)

2142(2)

27(2)

C(32)

5070(3)

3841(3)

1946(2)

28(2)

C(33)

5700(3)

3992(3)

1685(2)

23(1)

C(34)

5949(3)

4755(3)

1620(2)

21(1)

C(35)

6536(3)

4945(3)

1300(2)

19(1)

C(36)

7121(3)

5511(3)

1365(2)

20(1)

C(37)

7663(3)

5623(3)

1026(2)

24(1)

C(38)

7556(3)

5219(3)

650(2)

28(2)

C(39)

6968(3)

4677(3)

580(2)

23(1)

C(40)

6468(3)

4540(3)

918(2)

21(1)

C(41)

8366(3)

C(42)

8896(3)

C(43)

8117(4)

C(44)

8848(4)

C(45)

6810(4)

C(46)

6024(3)

C(47)

Cl(1) Cl(2) O(3) C(50)

AC C

O(4)

C(51)

SC 1081(2)

31(2)

5813(4)

1422(2)

50(2)

6996(3)

1214(2)

44(2)

6254(4)

676(2)

56(2)

4291(3)

150(2)

30(2)

4595(4)

-18(2)

43(2)

6753(4)

3399(3)

197(2)

44(2)

7442(4)

4477(4)

-173(2)

49(2)

1582(4)

2041(3)

1445(2)

46(2)

1262(1)

1289(1)

1140(1)

94(1)

1093(1)

2923(1)

1368(1)

91(1)

4917(5)

9314(6)

331(3)

45(2)

4245(8)

8673(7)

357(4)

55(3)

5407(5)

9457(5)

-46(3)

45(2)

4765(8)

9729(11)

238(5)

55(3)

TE D

C(49)

6168(3)

EP

C(48)

RI PT

C(27)

M AN U

ACCEPTED MANUSCRIPT

________________________________________________________________________________

21

ACCEPTED MANUSCRIPT Table S10. Bond lengths [Å ] and angles [°] for complex 5.

2.034(3)

Zn-N(1)

2.161(5)

Zn-N(2)

2.178(4)

Zn-N(4)

2.180(4)

Zn-N(3)

2.228(4)

O(1)-C(12)

1.312(6)

O(2)-C(36)

1.307(6)

N(1)-C(5)

1.348(6)

N(1)-C(1)

1.353(7)

N(2)-C(10)

1.355(6)

N(2)-C(6)

1.355(7)

N(3)-C(25)

1.349(6)

N(3)-C(29)

1.363(6)

N(4)-C(30)

1.341(6)

N(4)-C(34)

1.358(6)

C(1)-C(2)

1.375(8)

C(2)-C(3)

1.366(8)

C(3)-C(4)

1.383(8)

C(5)-C(6) C(6)-C(7) C(7)-C(8) C(8)-C(9) C(9)-C(10)

1.478(7) 1.388(7) 1.379(7)

AC C

C(10)-C(11)

1.381(7)

EP

C(4)-C(5)

SC

Zn-O(2)

M AN U

1.990(3)

TE D

Zn-O(1)

RI PT

_____________________________________________________

1.373(7) 1.407(7) 1.493(7)

C(11)-C(16)

1.398(7)

C(11)-C(12)

1.413(7)

C(12)-C(13)

1.449(7)

C(13)-C(14)

1.367(7)

C(13)-C(17)

1.531(7)

C(14)-C(15)

1.422(7)

C(15)-C(16)

1.370(7)

C(15)-C(21)

1.549(7)

C(17)-C(20)

1.539(7)

C(17)-C(18)

1.540(7)

22

1.523(8)

C(21)-C(23)

1.533(7)

C(21)-C(24)

1.540(7)

C(25)-C(26)

1.380(7)

C(26)-C(27)

1.386(8)

C(27)-C(28)

1.386(7)

C(28)-C(29)

1.382(7)

C(29)-C(30)

1.485(7)

C(30)-C(31)

1.393(7)

C(31)-C(32)

1.392(7)

C(32)-C(33)

1.388(7)

C(33)-C(34)

1.387(7)

C(34)-C(35)

1.466(7)

C(35)-C(40)

1.398(7)

C(35)-C(36)

1.411(7)

C(36)-C(37)

1.436(7)

C(37)-C(38)

1.387(7)

C(37)-C(41)

1.535(7)

C(38)-C(39)

1.388(7)

C(39)-C(40)

1.390(7)

C(41)-C(44) C(41)-C(43) C(41)-C(42) C(45)-C(48) C(45)-C(47)

1.532(7) 1.537(7) 1.539(8)

AC C

C(45)-C(46)

1.536(7)

EP

C(39)-C(45)

SC

C(21)-C(22)

M AN U

1.542(7)

TE D

C(17)-C(19)

RI PT

ACCEPTED MANUSCRIPT

1.525(7) 1.535(7) 1.542(8)

C(49)-Cl(1)

1.697(6)

C(49)-Cl(2)

1.743(6)

O(3)-C(50)

1.596(12)

O(4)-C(51)

1.498(13)

O(1)-Zn-O(2)

89.97(14)

O(1)-Zn-N(1)

160.11(16)

O(2)-Zn-N(1)

90.75(15)

O(1)-Zn-N(2)

85.76(15)

O(2)-Zn-N(2)

107.74(15)

23

O(1)-Zn-N(4)

102.95(14)

O(2)-Zn-N(4)

85.60(15)

N(1)-Zn-N(4)

96.92(17)

N(2)-Zn-N(4)

164.26(16)

O(1)-Zn-N(3)

92.27(15)

O(2)-Zn-N(3)

158.72(15)

N(1)-Zn-N(3)

94.23(16)

N(2)-Zn-N(3)

93.53(16)

N(4)-Zn-N(3)

73.28(16) 126.0(3)

C(36)-O(2)-Zn

120.9(3)

C(5)-N(1)-C(1)

118.5(5)

C(5)-N(1)-Zn

116.3(4)

C(1)-N(1)-Zn

124.3(4)

C(10)-N(2)-C(6)

118.6(5)

C(10)-N(2)-Zn

124.6(4)

C(6)-N(2)-Zn

115.0(4)

C(25)-N(3)-C(29)

117.4(5)

C(25)-N(3)-Zn

126.9(4)

C(29)-N(3)-Zn

115.5(4)

C(30)-N(4)-C(34)

C(34)-N(4)-Zn N(1)-C(1)-C(2) C(3)-C(2)-C(1) C(2)-C(3)-C(4)

115.3(3) 121.8(4) 123.2(6)

AC C

C(5)-C(4)-C(3)

119.3(5)

EP

C(30)-N(4)-Zn

TE D

C(12)-O(1)-Zn

SC

75.10(17)

M AN U

N(1)-Zn-N(2)

RI PT

ACCEPTED MANUSCRIPT

118.4(7) 118.9(7) 120.7(6)

N(1)-C(5)-C(4)

120.3(6)

N(1)-C(5)-C(6)

115.6(5)

C(4)-C(5)-C(6)

124.2(6)

N(2)-C(6)-C(7)

122.9(6)

N(2)-C(6)-C(5)

115.5(5)

C(7)-C(6)-C(5)

121.6(5)

C(8)-C(7)-C(6)

118.7(6)

C(9)-C(8)-C(7)

118.9(6)

C(8)-C(9)-C(10)

120.8(6)

N(2)-C(10)-C(9)

119.9(5)

24

120.0(5)

C(16)-C(11)-C(12)

120.6(5)

C(16)-C(11)-C(10)

117.2(5)

C(12)-C(11)-C(10)

122.2(5)

O(1)-C(12)-C(11)

123.3(5)

O(1)-C(12)-C(13)

119.6(5)

C(11)-C(12)-C(13)

117.0(5)

C(14)-C(13)-C(12)

119.5(5)

C(14)-C(13)-C(17)

120.1(5)

C(12)-C(13)-C(17)

120.4(5)

C(13)-C(14)-C(15)

123.6(5)

C(16)-C(15)-C(14)

116.2(5)

C(16)-C(15)-C(21)

124.4(5)

C(14)-C(15)-C(21)

119.3(5)

C(15)-C(16)-C(11)

123.1(5)

C(13)-C(17)-C(20)

112.1(4)

C(13)-C(17)-C(18)

108.6(5)

C(20)-C(17)-C(18)

108.8(5)

C(13)-C(17)-C(19)

112.9(4)

C(20)-C(17)-C(19)

106.9(5)

C(18)-C(17)-C(19) C(22)-C(21)-C(23) C(22)-C(21)-C(24)

107.1(5) 108.7(5) 107.8(5) 107.7(5)

EP

C(23)-C(21)-C(24)

SC

C(9)-C(10)-C(11)

M AN U

119.9(5)

TE D

N(2)-C(10)-C(11)

RI PT

ACCEPTED MANUSCRIPT

109.7(5)

C(23)-C(21)-C(15)

112.8(5)

C(24)-C(21)-C(15)

109.9(5)

N(3)-C(25)-C(26)

123.6(6)

C(25)-C(26)-C(27)

118.3(6)

C(28)-C(27)-C(26)

119.2(6)

C(29)-C(28)-C(27)

119.4(6)

N(3)-C(29)-C(28)

122.0(5)

N(3)-C(29)-C(30)

114.1(5)

C(28)-C(29)-C(30)

123.7(5)

N(4)-C(30)-C(31)

123.2(5)

N(4)-C(30)-C(29)

115.5(5)

C(31)-C(30)-C(29)

121.3(5)

AC C

C(22)-C(21)-C(15)

25

119.4(5)

C(34)-C(33)-C(32)

120.3(5)

N(4)-C(34)-C(33)

120.2(5)

N(4)-C(34)-C(35)

118.1(5)

C(33)-C(34)-C(35)

121.5(5)

C(40)-C(35)-C(36)

121.7(5)

C(40)-C(35)-C(34)

115.5(5)

C(36)-C(35)-C(34)

122.8(5)

O(2)-C(36)-C(35)

120.9(5)

O(2)-C(36)-C(37)

122.6(5)

C(35)-C(36)-C(37)

116.4(5)

C(38)-C(37)-C(36)

119.2(5)

C(38)-C(37)-C(41)

120.3(5)

C(36)-C(37)-C(41)

120.5(5)

C(37)-C(38)-C(39)

124.4(5)

C(38)-C(39)-C(40)

116.1(5)

C(38)-C(39)-C(45)

123.8(5)

C(40)-C(39)-C(45)

119.9(5)

C(39)-C(40)-C(35)

122.0(5)

C(44)-C(41)-C(37)

112.9(5)

C(44)-C(41)-C(43) C(37)-C(41)-C(43) C(44)-C(41)-C(42)

106.9(5) 111.8(5) 107.6(5) 107.9(5)

EP

C(37)-C(41)-C(42)

SC

C(33)-C(32)-C(31)

M AN U

117.4(5)

TE D

C(32)-C(31)-C(30)

RI PT

ACCEPTED MANUSCRIPT

109.6(5)

C(48)-C(45)-C(47)

108.4(5)

C(48)-C(45)-C(39)

112.2(5)

C(47)-C(45)-C(39)

110.7(5)

C(48)-C(45)-C(46)

108.9(5)

C(47)-C(45)-C(46)

108.1(5)

C(39)-C(45)-C(46)

108.4(5)

Cl(1)-C(49)-Cl(2)

114.7(4)

AC C

C(43)-C(41)-C(42)

_____________________________________________________________ Symmetry transformations used to generate equivalent atoms:

26

ACCEPTED MANUSCRIPT Table S11. Anisotropic displacement parameters (Å 2x 103) for complex 5. The anisotropic displacement factor exponent takes the form: -22[ h2 a*2U11 + ... + 2 h k a* b* U12 ] ______________________________________________________________________________ U11

U22

U33

U23

U13

U12

______________________________________________________________________________ 19(1)

21(1)

23(1)

-2(1)

-1(1)

-1(1)

O(1)

25(2)

17(2)

20(2)

-6(2)

-5(2)

1(2)

O(2)

19(2)

19(2)

26(2)

-4(2)

2(2)

1(2)

N(1)

21(3)

28(3)

31(3)

-1(3)

-3(2)

3(2)

N(2)

20(3)

18(3)

24(3)

-1(2)

-1(2)

5(2)

N(3)

22(3)

24(3)

26(3)

-6(2)

1(2)

-2(2)

N(4)

19(3)

19(3)

15(3)

2(2)

-3(2)

1(2)

C(1)

36(4)

35(4)

32(4)

0(3)

-1(3)

1(3)

C(2)

57(5)

57(5)

27(4)

3(4)

-6(4)

-15(4)

C(3)

90(7)

66(6)

27(4)

5(4)

-14(4)

-24(5)

C(4)

68(5)

42(4)

44(5)

11(4)

-2(4)

-18(4)

C(5)

23(4)

28(4)

26(4)

1(3)

4(3)

-4(3)

C(6)

20(3)

24(4)

32(4)

3(3)

2(3)

3(3)

C(7)

28(4)

23(4)

34(4)

4(3)

1(3)

0(3)

C(8)

32(4)

19(4)

41(4)

2(3)

10(3)

-5(3)

C(9)

22(3)

25(4)

36(4)

-11(3)

0(3)

-4(3)

C(10)

13(3)

16(3)

34(4)

-3(3)

2(3)

5(3)

C(11)

10(3)

23(3)

24(3)

-3(3)

-2(3)

2(3)

C(12)

14(3)

25(4)

24(4)

4(3)

0(3)

0(3)

C(13)

21(3)

24(3)

19(3)

-1(3)

-7(3)

4(3)

C(14)

19(3)

24(3)

27(3)

-2(3)

1(3)

-1(3)

C(15)

20(3)

25(4)

24(4)

-5(3)

-4(3)

6(3)

C(16)

22(3)

19(3)

28(4)

-4(3)

-6(3)

0(3)

C(17)

28(4)

22(3)

19(3)

1(3)

-4(3)

5(3)

C(18)

33(4)

26(4)

45(4)

-4(3)

-9(3)

5(3)

C(19)

60(5)

22(4)

30(4)

1(3)

-11(4)

-5(3)

C(20)

45(4)

25(4)

36(4)

-1(3)

-4(3)

-4(3)

C(21)

30(4)

30(4)

25(4)

-9(3)

-5(3)

-2(3)

C(22)

45(5)

39(4)

41(4)

-11(4)

7(4)

4(3)

C(23)

73(6)

33(4)

31(4)

-14(3)

4(4)

-10(4)

C(24)

48(5)

57(5)

29(4)

-19(4)

-8(3)

13(4)

C(25)

24(4)

29(4)

30(4)

-9(3)

-4(3)

-2(3)

C(26)

24(4)

34(4)

49(4)

-18(3)

4(3)

3(3)

SC

M AN U

TE D

EP

AC C

RI PT

Zn

27

ACCEPTED MANUSCRIPT 19(4)

42(4)

34(4)

-9(3)

1(3)

0(3)

C(28)

21(4)

32(4)

37(4)

-9(3)

1(3)

-8(3)

C(29)

24(3)

21(3)

17(3)

3(3)

-5(3)

1(3)

C(30)

18(3)

29(4)

11(3)

0(3)

-3(3)

-4(3)

C(31)

23(3)

32(4)

27(4)

5(3)

2(3)

-4(3)

C(32)

31(4)

23(4)

31(4)

1(3)

-6(3)

-5(3)

C(33)

30(4)

15(3)

24(4)

0(3)

-4(3)

-3(3)

C(34)

25(3)

17(3)

21(3)

5(3)

-7(3)

-2(3)

C(35)

14(3)

21(3)

20(3)

0(3)

-2(3)

0(3)

C(36)

25(3)

18(3)

17(3)

-2(3)

2(3)

4(3)

C(37)

24(3)

16(3)

32(4)

1(3)

0(3)

1(3)

C(38)

26(4)

30(4)

27(4)

-1(3)

5(3)

0(3)

C(39)

28(4)

21(4)

20(3)

-5(3)

2(3)

2(3)

C(40)

19(3)

15(3)

29(4)

-1(3)

1(3)

-3(3)

C(41)

24(4)

30(4)

38(4)

-1(3)

12(3)

-11(3)

C(42)

24(4)

44(4)

82(6)

-14(4)

-10(4)

-3(3)

C(43)

35(4)

41(4)

54(5)

-8(4)

7(4)

-14(3)

C(44)

38(4)

57(5)

73(5)

-19(4)

30(4)

-26(4)

C(45)

40(4)

31(4)

17(3)

1(3)

2(3)

-4(3)

C(46)

44(5)

56(5)

29(4)

-3(4)

-4(3)

5(4)

C(47)

69(5)

31(4)

32(4)

-15(3)

-1(4)

-4(4)

C(48)

51(5)

73(5)

24(4)

-9(4)

17(4)

-10(4)

C(49)

44(5)

45(5)

48(5)

0(4)

-3(4)

-10(4)

Cl(1)

78(2)

103(2)

101(2)

-66(2)

-48(1)

42(2)

Cl(2)

81(2)

48(1)

144(2)

23(1)

20(2)

10(1)

EP

TE D

M AN U

SC

RI PT

C(27)

AC C

______________________________________________________________________________

28

ACCEPTED MANUSCRIPT Table S12. Hydrogen coordinates ( x 104) and isotropic displacement parameters (Å 2x 10 3) complex 5. ________________________________________________________________________________ x

y

z

U(eq)

________________________________________________________________________________

5532

6157

1064

41

H(2)

5493

6771

413

57

H(3)

5960

8050

355

H(4)

6454

8670

956

H(7)

7029

9119

1501

H(8)

7611

9551

2130

H(9)

7487

8791

2736

33

H(14)

6226

6572

3909

28

H(16)

6672

8495

3219

28

H(18A)

7288

H(18B)

7171

H(18C)

7572

H(19A)

6567

H(19B)

6154

H(19C)

5662

H(20A)

M AN U

SC

RI PT

H(1)

73 61 34 37

2945

52

4529

3305

52

5348

3417

52

5384

4000

56

4613

3821

56

5399

3885

56

5251

5309

3112

53

5729

4505

3114

53

5907

5154

2763

53

5491

7405

4311

62

5119

8069

4018

62

5446

8289

4476

62

6340

9280

4231

68

5994

9176

3765

68

H(23C)

6911

9115

3842

68

H(24A)

6864

8183

4624

67

H(24B)

7457

7982

4250

67

H(24C)

6886

7320

4427

67

H(25)

4995

7720

2347

33

H(26)

3763

7770

2642

43

H(27)

3029

6610

2686

38

H(28)

3570

5436

2439

36

H(31)

4249

4378

2317

33

H(32)

4900

3319

1991

34

H(20C) H(22A) H(22B) H(22C) H(23A)

AC C

H(23B)

EP

H(20B)

TE D

5175

29

ACCEPTED MANUSCRIPT 5962

3572

1550

27

H(38)

7908

5319

425

33

H(40)

6069

4161

888

25

H(42A)

8595

5724

1681

75

H(42B)

9324

6175

1482

75

H(42C)

9107

5314

1321

75

H(43A)

7781

7222

996

65

H(43B)

8580

7325

1250

H(43C)

7832

6969

1482

H(44A)

9053

5742

593

H(44B)

9281

6615

728

H(44C)

8519

6461

450

84

H(46A)

5618

4497

193

64

H(46B)

5893

4322

-280

64

H(46C)

6061

H(47A)

7258

H(47B)

6606

H(47C)

6359

H(48A)

7465

H(48B)

7322

H(48C)

SC

M AN U

65 65 84 84

5158

-72

64

3190

286

66

3167

-75

66

3270

409

66

5044

-218

74

4215

-440

74

7944

4292

-67

74

2141

2124

1387

55

TE D

H(49A)

RI PT

H(33)

AC C

EP

H(49B) 1532 1889 1746 55 ________________________________________________________________________________

30