The syntheses, characterization and photophysical properties of phosphine copper(I) and silver(I) complexes with the bispyridylpyrrolide ligand

Accepted Manuscript The syntheses, characterization and photophysical properties of phosphine copper(I) and silver(I) complexes with the bispyridylpyrrolide ligand Ya-Ping Wang, Xiao-Hui Hu, Yi-Fan Wang, Jun Pan, Xiao-Yi Yi PII: DOI: Reference:

S0277-5387(15)00656-7 http://dx.doi.org/10.1016/j.poly.2015.10.057 POLY 11643

To appear in:

Polyhedron

Received Date: Accepted Date:

15 July 2015 30 October 2015

Please cite this article as: Y-P. Wang, X-H. Hu, Y-F. Wang, J. Pan, X-Y. Yi, The syntheses, characterization and photophysical properties of phosphine copper(I) and silver(I) complexes with the bispyridylpyrrolide ligand, Polyhedron (2015), doi: http://dx.doi.org/10.1016/j.poly.2015.10.057

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The syntheses, characterization and photophysical properties of phosphine copper(I) and silver(I) complexes with the bispyridylpyrrolide ligand Ya-Ping Wang,a Xiao-Hui Hu,a Yi-Fan Wang,a Jun Pan,b Xiao-Yi Yi*a a

School of Chemistry and Chemical Engineering, Central South University, Changsha,

Hunan 410083, P. R. China. Fax: 86 731 88879616; Tel: 86 731 88879616; b

State Key Laboratory for Powder Metallurgy, Central South University, Changsha, Hunan

410083, P. R. China. E-mail: [email protected]

Abstract Five mononuclear copper(I) complexes and one dinuclear silver(I) phosphine complex containing the bispyridylpyrrole ligand were synthesized and structurally characterized. Treatment of CuCl and the deprotonated bispyridylpyrrole ligand with bis(phosphine) ligands afforded the copper(I) complexes [(PDPH)Cu(XANTPhos)] (1), [(PDPH)Cu(DPEPhos)] (2), [(PDPBr)Cu(XANTPhos)] (3) and [(PDPBr)Cu(DPEPhos)] (4), while addition of two equivalences of PPh3 gave [(PDPBr)Cu(PPh3)2] (5), where PDPH- = 2,5bis(2-pyridyl)pyrrole, PDPBr- = 2,5-bis(6’-bromo-2’-pyridyl)-pyrrole, XANTPhos = 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene,

DPEPhos

=

oxydi-2,1-phenylene)bis-

-

diphenylphosphine. Reaction of PDPBr with AgOTf and DPEPhos yielded the dinuclear silver(I) complex [(PDPBr)Ag2(DPEPhos)](OTf) (6). All of these complexes were fully characterized on the basis of IR spectra, 1H and 31P NMR spectra, elements analysis, UV-vis spectra and X-ray single crystal diffraction analysis. The photophysical properties of these complexes were also studied.

1

1. Introduction Luminescent Cu(I) complexes have gained increasing interest for their potential application in organic light emitting devices, as they not only are abundant and cost-efficient, but also offer a new path to efficient emitters that can make use of both singlet and triplet excitons [1]. Since the first example of a highly emissive mononuclear copper complex, [Cu(dmp)(DPEPhos)]+ (where dmp = 2,9-dimethyl-1,10-phenanthroline, DPEPhos = bis[2(diphenylphosphino)phenyl]ether) was reported by McMillin’s group [2], a great number of analogous complexes with the general formula [Cu(N^N)(P^P)]n+ (n = 0 or 1) have been reported in the literature, where N^N represents a bi- or tridentate nitrogen ligand and P^P denotes chelating diphosphines [3]. As far as N^N type ligands are concerned, a wide range of nitrogen donor ligands, such as 4,4'-diphenyl-2,2'-biquinoline, 3,3'-methylen-4,4'diphenyl-2,2'-biquinoline, N-(4-(carbazol-9-yl)phenyl)-3,6-bis(carbazol-9-yl)carbazole, 2,9di-n-butyl-1,10-phenanthroline,

2,9-diphenyl-1,10-phenanthroline,

2,9-diisopropyl-1,10-

phenanthroline, have been employed so far. Among the many examples that have gained a prominent role in the design of Cu(I) complexes, we have a long-standing interest in metal complexes based on the mono-anionic bispyridylpyrrole (PDP-) ligand [4-6]. This N3 ligand usually behaves as a bi- or tri-dentated ligand upon complexation with metals (Scheme 1). Aiming at further widening the family of photoactive Cu(I) complexes, herein we will describe the preparation, characterization and study of the photophysical properties of a set of neutral [Cu(N^N)(P^P)]-type mono-copper(I) complexes, where N^N is the PDP- ligand and P^P is a neutral chelating diphosphine or two triphenylphosphine ligands. The element of novelty in the present work is given by the use of the pincer-like PDP- ligand as the anionic chelating bidentate ligand. The use of the PDP- ligand with this kind of coordination mode, as an excellent and versatile component, further develops our studies of photoactive Ir(III) complexes.

2. Experimental 2.1 General considerations All manipulations were carried out under nitrogen by standard Schlenk techniques unless otherwise stated. Solvents were purified, distilled and degassed prior to use. 1H and 31P NMR spectra were recorded on a Bruker AV 400 spectrometer operating at 400 and 161 MHz, and chemical shifts (δ, ppm) were reported with reference to SiMe4 and H3PO4, respectively. Infrared spectra (KBr) were recorded on a AVATR360 FT-IR spectrophotometer. UV-Vis spectra were recorded on a UV759S machine. The starting 2,5-bis(2’-pyridyl)pyrrole 2

(HPDPH) [12, 13] and 2,5-bis(6’-bromo-2’-pyridyl)pyrrole (HPDPBr) [14,15] were prepared according to literature methods. All of the other chemicals were obtained from J&K Scientific Ltd.

2.2 [(PDPH)Cu(XANTPhos)] (1) To a solution of HPDPH (35.5 mg, 0.16 mmol) in THF (6 mL) was added NaH (60%, 6.51 mg, 0.16 mmol) to form a yellow solution. After stirring for 10 min, CuCl (15.87 mg, 0.16 mmol) and XANTPhos (92.85, mg, 0.16 mmol) were added. The yellow resulting solution was stirred overnight and filtered. The filtrate was layered with hexane to give yellow crystals which were suitable for an X-ray diffraction study. Isolated yield: 65.8 mg (47.4%). 1

H NMR (CDCl3, δ, ppm): 8.56-8.55 (d, J = 2 Hz, 2H), 7.94-7.93 (d, J = 2 Hz, 2H), 7.74-7.72

(d, J = 4 Hz, 2H), 7.54-7.52 (m, 2H), 7.14-7.07 (m, 20H), 7.03-7.01 (t, J = 4 Hz, 2H), 6.696.67 (d, J = 4 Hz, 2H), 6.61-6.57 (m, 2H), 6.50-6.44 (m, 2H), 1.79 (s, 6H); 31P NMR (CDCl3, δ, ppm): -16.06 (s, XANTPhos). IR (KBr, cm-1): 3049(w), 2964(w), 1596(s), 1508(m), 1428(s), 1402(s), 1324(s), 1223(s), 1149(w), 1098(w), 848(w), 748(s), 694(s), 508(s). Anal. Calcd for: C53H42CuN3OP2: C, 73.81; H, 4.91; N, 4.87. Found: C, 73.83; H, 4.92; N, 4.80 %. The exactly same procedure was operated to prepare complexes 2-4, only using HPDPBr in place of HPDPH, or DPEPhos instead of XANTPhos. In 5, PPh3 was used. 2.3 [(PDPH)Cu(DPEPhos)] (2) Isolated yield: 57.9 mg (42.1%). 1H NMR (CDCl3, δ, ppm): 8.55-8.54 (d, J = 2 Hz, 2H) 7.847.83 (d, J = 2 Hz, 2H), 7.77-7.76 (d, J = 2 Hz, 2H), 7.15-7.07 (m, 14H), 7.14-7.01 (m, 10H), 6.81 (s, 2H), 6.75-6.73 (m, 2H), 6.68-6.67 (d, J = 2 Hz, 2H), 6.64-6.60 (m, 2H);

31

P NMR

(CDCl3, δ, ppm): -19.3 (s, DPEPhos). IR (KBr, cm-1): 3047(w), 1583(s), 1508(m), 1430(s), 1321(m), 1256(w), 1216(m), 1152(w), 744(s), 695(s), 507(m). Anal. Calcd for: C50H38CuN3OP2: C, 73.03; H, 4.66; N, 5.11. Found: C, 73.59; H, 4.92; N, 4.98 %. 2.4 [(PDPBr)Cu(XANTPhos)] (3) Isolated yield: 49.8 mg (30.5%). 1H NMR (CDCl3, δ, ppm): 7.41-7.40 (d, J = 2 Hz, 2H), 7.27-7.26 (d, J = 2 Hz, 2H), 7.20-7.10 (m, 12H), 7.04-6.99 (m, 10H), 6.81 (s, 2H), 6.76-6.72 (m, 2H), 6.67-6.66 (d, J = 2 Hz, 2H), 6.54-6.50 (t, 2H), 1.57 (s, 6H);

31

P NMR (CDCl3, δ,

-1

ppm): -16.06 (s, XANTPhos). IR (KBr, cm ): 3046(w), 2967(w), 1541(s), 1485(m), 1406(s), 1311(m), 1219(m), 1148(m), 1097(w), 978(w), 753(s), 694(m), 508(m). Anal. Calcd for C53H40Br2CuN3OP2·(THF): C, 62.68; H, 4,42; N, 3.85; Found: C, 62.44; H, 4.71; N, 3.65 %. 3

2.5 [(PDPBr)Cu(DPEPhos)] (4) Isolated yield: 45.6 mg (37%). 1H NMR (CDCl3, δ, ppm): 7.41-7.40 (d, J = 2 Hz, 2H), 7.267.25 (d, J = 2 Hz, 2H), 7.09-7.03 (m, 12H), 7.01-6.98 (m, 12H), 6.80 (s, 2H), 6.75-6.72 (m, 2H), 6.66-6.65 (d, J = 2 Hz, 2H), 6.55-6.50 (m, 2H);

31

P NMR (CDCl3, δ, ppm): -15.64 (s,

DPEPhos). IR (KBr, cm-1): 3051(s), 1578(m), 1460(m), 1434(s), 1255(w), 1218(s), 1096(w), 747(s), 696(s), 504(m). Anal. Calcd for C50H36Br2CuN3OP2: C, 61.27; H, 3.70; N, 4.29. Found: C, 61.48; H, 3.53; N, 4.41 %.

2.6 [(PDPBr)Cu(PPh3)2] (5) Isolated yield: 38 mg (39%). 1H NMR (CDCl3, δ, ppm): 7.73-7.67 (m, 2H), 7.62-7.54 (m, 18H), 7.52-7.46 (m, 10H), 7.12-7.07 (m, 6H), 6.68-6.67 (d, J = 2 Hz, 2H); 31P NMR (CDCl3, δ, ppm): -3.5 (s, PPh3). IR (KBr, cm-1): 3042(w), 1576(s), 1498(m), 1430(s), 1316(s), 1272(w),

1147(m),

1085(w),

989(w),

742(s),

691(s),

494(m).

Anal.

Calcd for

C50H38Br2CuN3P2: C, 62.16; H, 3.96; N, 4.35. Found: C, 62.38; H, 4.15; N, 4.11 %. 2.7 [(PDPBr)Ag2(DPEPhos)](OTf) (6) To a solution of HPDPBr (76.7 mg, 0.20 mmol) in THF (6 mL) was added NaH (13.6 mg, 0.20 mmol). After stirring for 10 min, AgOTf (104 mg, 0.40 mmol) and DPEPhos (108.9. mg, 0.20 mmol) were added. The yellow resulting solution was stirred overnight and filtered. The filtrate was layered with hexane to give yellow crystals which were suitable for an X-ray diffraction study. Yield: 65 mg (32%). 1H NMR (CDCl3, δ, ppm): 7.86-7.80 (m, 4H), 7.537.47 (m, 4H), 7.42-7.22 (m, 21H), 7.07-7.04 (t, J = 4 Hz, 4H), 6.74-6.70 (m, 2H), 6.62-6.59 (m, 2H). 31P NMR (CDCl3, δ, ppm): 6.63(d, J = 19 Hz), 3.14 (d, J = 19 Hz). IR (KBr, cm-1): 3047(w), 1580(s), 1484(m), 1434(s), 1409(s), 1266(s), 1161(m), 1034(m), 749(s), 692(m), 634(m). Anal. Calcd for: C51H36Br2Ag2N3O4P2F3S: 47.82; H, 2.83; N, 3.27; Found: C, 47.53; H, 2.93; N, 3.38 %.

2.8 X-ray crystallography. Diffraction data of 1-3, 5 and 6 were recorded on a Bruker CCD diffractometer with monochromatized Mo-Kα radiation (λ = 0.71073 Å). The collected frames were processed with the software SAINT. Absorption corrections were treated with SADABS [16]. The structures were solved by direct methods and refined by full-matrix least-squares on F2 using

4

the SHELXTL software package [17]. Atomic positions of non-hydrogen atoms were refined with anisotropic parameters. All hydrogen atoms were introduced at their geometric positions and refined as riding atoms. The PDPH- ligand in 2 and triflato ligand in 6 were treated with disorder.

3. Results and Discussion 3.1 Synthesis and characterization In our previous study, we found CuCl reacted with deprotonated PDPH- to yield the air-sensitive red sodium-copper(I) complex [Cu(PDPH)2Na(THF)2], which readily afforded the Cu(II) complex [Cu(PDPH)Cl] by an oxidation reaction [6]. Interestingly, when the bis(phosphine) ligands were added into the red reaction mixture of CuCl and PDPH-, the color turned to yellow immediately. As shown in Scheme 2, The mono-copper(I) phosphine complexes 1-5, containing the bispyridylpyrrole ligand, were isolated. In comparison, treatment of AgOTf, PDPBr- and DPEPhos afforded the dinuclear silver(I) phosphine complex 6. It is worth noting that, in our previous study, the reaction of AgOTf and HPDPBr in the absence of base afforded the ionic [(HPDPBr)Ag]22+ [4]. When AgOTf was treated with deprotonated PDPH- in the presence of monodentate phosphine donors, such as PPh3 and HP(O)(OEt)2,

it

gave

[Ag{(PDPH)Ag(PPh3)}2]+

trinuclear

and

dinuclear

-

[(PDPH)Ag2{P(O)(OEt)2}2] [4], respectively. Complexes 1-6 are air-stable, and readily soluble in organic solvents, such as THF, CH2Cl2 and CH3CN, but are insoluble in water and non-polar solvents. All of these complexes were fully characterized on the basis of IR spectra, 1

H and 31P NMR spectra, elements analysis and X-ray single crystal diffraction analysis. In all cases, the IR spectra clearly display that the copper atom coordinates to the

pyrrole nitrogen atom, resulting in the absence of the imino N-H resonance of the bispyridylpyrrole ligand, which is consistent with the 1H NMR spectra. Several distinctive signals at 3050 cm-1, due to C-H stretching, and 1430 to 1596 cm-1, attributed to C=C and C=N in-plane vibrations, are observed. In complex 6, intense bands at 1261-1034 cm-1 are due to the S=O bond of the OTf- group. The 31P NMR spectra of 1-5 each show a broad peak at δ -15.64 to 19.30 ppm, which is similar to that found in mono-pyridylpyrrole, pyrrole-, indole-aldimine copper(I) phosphine complexes [18-20]. The broadening of the peak is apparently due to the quadruple

63

Cu and

65

31

P NMR

Cu nuclei, possessing a magnetic spin

1

quantum number I = 3/2. The H NMR spectra show a doublet of peaks at 6.66 ppm, assigned to the proton resonances of the pyrrole ring, and multiply peaks at 7.01-7.45 ppm for the pyridyl ring and phenyl rings of the phosphine ligands [4-6,21,22]. Only small changes are 5

found for these signals, indicating that the electronic environments of the ligands remain relatively similar with to each other.

3.2 Description of the structures The crystallographic data and experimental details for 1-3, 5 and 6 are shown in Table 1. Selected bond distances and angles are listed in Tables 2 and 3. The ORTEP diagrams of complexes 1-3, 5 and 6 are displayed in Figures 1-5, respectively. Complexes 1-3 and 5 have similar structures, including one copper(I) atom, one bispyridylpyrrole and one bis(phosphine) ligand (or two triphenylphosphine ligands for 5). Each copper(I) atom is coordinated by two N atoms from the bispyridylpyrrole ligand and two P atoms from the bis(phosphine) ligand (or from two triphenylphosphine ligands for 5), generating a {CuN2P2} distorted tetrahedral geometry. The pendant pyridyl substituent does not coordinate, maybe due to the steric effect of the neighboring bulky PPh3 groups. This uncoordinated pyridine is tilted out of plane from the pyridylpyrrole unit, with dihedral angles varying from 4.8 to 23.8 o. Notably, it is the first time that a bispyridylpyrrole ligand behaves as a “monopyridylpyrrole’ bidentate ligand with κ2-(N,N’) bonding mode V (Scheme 1). In these complexes, the Cu-P distances are 2.2412.289 Å, which are practically identical with each other and those in the copper(I) phosphine complexes reported in the literature [18-20]. The Cu-N(pyrrole) bond distance (2.028-2.057 Å) is slightly shorter than that of Cu-N(pyridine) (2.083-2.222 Å), which can be explained by the stronger coordination of the deprotonated pyrrole nitrogen donor to the metal centre versus the neutral pyridyl group [21,22]. The chelating N-Cu-N angle is very similar among these complexes (80.73-81.48o), however, the P-Cu-P bite angle varies more, i.e. 114.6 o for 1, 111.814 o for 2, 118.71 o for 3 and 123.65 o for 5. The dihedral angles between the N-Cu-N and P-Cu-P planes are 86.0_89.8 o, indicating a distorted tetrahedral geometry around the copper(I) ion. It is consistent with known complexes based on phosphine- or bis(phosphine) copper(I) complexes containing (N^N) donors. As shown in Figure 5, complex 6 is dinuclear, which is similar to that of [(PDPH)Ag2{P(O)(OEt)2}2]- [4]. In 6, PDPBr and DPEPhos, as bridging ligands, coordinate two silver atoms. Each silver(I) ion is three coordinated, by two N atoms from PDPBr- and one P atom from DPEPhos. The Ag-N(pyrrole) (2.295 Å) and Ag-N(pyridine) (2.320 Å) distances in 6 are longer than those in 1-3 and 5, possibly due to the greater steric repulsion pushing the coordinated bispyridylpyrrole ligand away from the adjacent PPh2 fragment. This repulsion also leads to a lengthening of the Ag-P distance to 2.341 Å. The distance between the two silver atoms in 6 is 2.859 Å, which is well comparable with those found in multi-nuclear 6

silver(I) complexes, indicating a weak Ag···Ag interaction [23,24]. It is presumed that this argentophilic interation may play a key role in forming the dinuclear silver complex 6.

3.3 Absorption and emission spectra of 1-4 The absorption spectra for 1-4 measured in CH2Cl2 at room temperature are shown in Figure 6. The high-energy bands in the range of 291-299 nm (ε > 4369 M-1 cm-1) are assigned to the π-π* transition of the bispyridylpyrrole and phosphine ligands. 1-2, with the PDPHligand, have intense absorption bands at 348 and 346 nm. The analogous absorption bands for 3 and 4 with the PDPBr- ligand are red-shifted by about 28 nm, which may be explained by the stronger coordination of the PDPBr- ligand to Cu(I), leading to an energetic stabilization of the molecular orbitals involved in the ligand centered transitions. Additional shoulders around 400 nm for 1, 399 nm for 2, 434 nm for 3 and 430 nm for 4, which are not observed for the free ligands, are assigned to metal-to-ligand charge transfer transitions (MLCT) on the basis of their extinction coefficients (ε = 1302-2800 M-1 cm-1) and by comparison to other metal phosphine complexes with the pyridylpyrrole ligand [25-27]. The solvent effect of 1 and 2 have been studied, which are evident in the absorption spectra (S1). The MLCT maximum shifts slightly to longer wavelengths in less polar solvents. The maximum shifts are from 390 nm in methanol and acetonitrile, to 402 nm in THF and DCM for 1, from 398 nm in methanol and acetonitrile to 410 nm in DCM for 2. The analogous behavior was observed in the [Cu(dmp)(DPEPhos)]+ complex (dmp = 2,9-di-n-butylphenanthroline) [2b]. Complexes 1-4 are not luminescent in the solid state, but show strong luminescence in the blue spectral region from 460-478 nm in DCM when excited at 420 nm in the MLCT region (Figure 6). Complexes 1 and 2 (472 nm for 1, 472 nm for 2) display red-shifted emission bands in contrast to 3 and 4 (468 nm for 3, 460 nm for 4). Solvent effects on the emissions from 1 and 2 are not apparent, possibly due to the relatively small dipole moment in the excited state. The emission maximum is relatively constant. For example, in DCM, the emission maximizes at 472 nm for 1 and 472 nm for 2, whereas in a more donor solvent, such as methanol, the emission maximum falls at 464 nm for 1 and 462 nm for 2 (S2).

4. Conclusions In

summary, five mononuclear copper(I) phosphine

complexes with the

bispyridylpyrrole ligand were synthesized by treatment of CuCl with the depronated bispyridylpyrrole ligand in the presence of phosphine ligands. Their crystal structures reveal

7

that the bispyridylpyrrole ligand behaves as a bidentate chelating ligand coordinating to the copper(I) ion. It is the first time that this kind of binding mode has been found for the bispyridylpyrrolide

ligand.

A

dinuclear

silver(I)

phosphine

complex

with

the

bispyridylpyrrole ligand was also prepared by a similar procedure, except AgOTf was used instead of CuCl. The bispyridylpyrrole ligand binds to two silver atoms with the µ2-κ2 (N,N’), κ2 (N’,N’’) bonding mode, leading to a short Ag···Ag separation. Possibly, this argentophilic interation plays a key role in forming the dinuclear silver complex 6. The strong luminescence of these complexes is in the blue spectral region from 460-478 nm in DCM, and the solvent effect on the absorption and emission spectra of 1 and 2 is evident.

Acknowledgments This work was supported by the National Natural Science Foundation of China (project 21441006), Open Fund of the State Key Laboratory of Medicinal Chemical Biology (Nankai University, 20140513) and the Open-End Fund for Valuable and Precision Instruments of Central South University (2015CXS004).

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[25] J.J. Klappa, S.A. Geers, S.J. Schmidtke, L.A. MacManus-Spencer, J. McNeil, Dalton Trans. (2004), 883-891. [26] J. Min, Q. Zhang, W. Sun, Y. Cheng, L. Wang, 40 (2011), 686-693. [27] X. Liu, H. Nan, W. Sun, Q. Zhang, M. Zhan, L. Zou, Z. Xie, X. Li, C. Lu, Y. Cheung, Dalton Trans. 41 (2012) 10199-10210.

10

Scheme 1 Coordination modes of the bispyridylpyrrole ligand

N

N N

N

N

N M

M

M R

R

R

R

I

II

N H

N N

N

N M

R

M

M R

R III

N M R

IV

N

R

N N M R

R = H or Br V

11

Scheme 2 The synthesis of complexes 1-6

N

N H

N

i) NaH, CuCl N

R

N

ii) 1 eq. Bis(phoshines) or 2 eq. PPh3

Cu

R

P

R

P

R = H, P^P = XANTPhos R = H, P^P = DPEPhos R = Br, P^P = XANTPhos R = Br, P^P = DPEPhos R = Br, P^P = 2 PPh3

N Br

N H

N

ii) 1 eq. DPEPhos Br

(1) (2) (3) (4) (5)

N

i) NaH, AgOTf N

R

N

Br

N Ag P

Ag

Br

P^P = DPEPhos

P 6

12

Table 1 Crystallographic data and experimental details for complexes 1-3, 5 and 6.

13

1

2

3

5

6

C53H42CuN3OP2

C50H38CuN3OP2

C53H40Br2CuN3OP2

C50H38Br2CuN3P2

C51H36Br2Ag2N3O4P2F3S

862.38

822.31

1020.18

966.13

988

Tetragonal

Monoclinic

Monoclinic

Orthorhombic

Monoclinic

P4(2)/n

P2(1)/n

P2(1)/n

Pbca

C21/c

a, Å

26.5901(13)

11.0996(2)

11.6671(8)

11.3977(7)

28.336(2)

b, Å

26.5901(13)

20.5748(3)

20.4028(14)

23.0960(13)

13.9824(10)

c, Å

12.2739(14)

17.1706(3)

19.0768(13)

35.539(2)

19.1958(15)

α, deg

90.00

90.00

90.00

90.00

90

β, deg

90.00

94.8380(10)

92.295(4)

90.00

122.465(4)

γ, deg

90.00

90.00

90.00

90.00

90

V, Å3

8678.1(12)

3907.31(11)

4537.4(5)

9355.3(9)

6416.9(8)

8

4

4

8

4

ρcalc, g cm-3

1.320

1.398

1.493

1.372

1.326

T, K

296(2)

296(2)

296(2)

293(2)

296(2)

µ, mm-1

0.620

0.685

2.356

2.280

1.984

F(000)

3584

1704

2064

3904

2528

no. of refln.

39343

47432

39085

10720

27489

no. of indep. refln.

8516

9006

10251

10720

7400

Rint

0.0609

0.0323

0.0493

0.0398

0.0362

GoF a

1.046

1.043

1.014

1.045

1.036

formula fw crystal system space group

Z

14

R1, b wR2 c [I > 2σ(I)]

0.0797,0.2203

0.0330,0.0837

0.0575,0.1319

0.0546,0.1440

0.0640, 0.2002

R1, wR2 (all data)

0.1347, 0.2505

0.0454,0.0910

0.1418,0.1652

0.1055,0.1586

0.0980, 0.2169

a

GoF = [Σw(|Fo| − |Fc|)2/(Nobs − Nparam)]½. b R1 = Σ||Fo| − |Fc||/Σ|Fo|. c wR2 [(Σw|Fo| − |Fc|)2/Σw2|Fo|2]½

15

Table 2 Selected bond distances (Å) and bond angles (o) for complexes 1-3 and 5. 1

2

3

5

Cu1-N1

2.083(7)

2.1133(15)

2.217(4)

2.222(3)

Cu1-N2

2.052(7)

2.0538(14)

2.028(3)

2.057(3)

Cu1-P1

2.255(6)

2.2410(5)

2.2698(11)

2.2780(9)

Cu1-P2

2.253(6)

2.2840(5)

2.2673(11)

2.2774(9)

N2-Cu1-N1

80.9(3)

81.48(6)

80.80(15)

80.73(11)

N2-Cu1-P2

123.5(3)

108.80(4)

117.52(10)

107.79(7)

N2-Cu1-P1

113.0(3)

132.02(4)

111.42(10)

117.53(7)

N1-Cu1-P1

105.2(3)

113.61(4)

111.42(9)

104.92(7)

N1-Cu1-P2

113.2(3)

101.36(4)

109.21(10)

114.13(7)

P2-Cu1-P1

114.6(2)

111.814(18)

118.71(4)

123.65(3)

Bond distances (Å)

Bond angles (o)

16

Table 3 The selected bond distances (Å) and bond angles (o) for complex 6 Ag1-N1

2.320(4)

Ag1-P1

2.3406(14)

Ag1-N2

2.295(5)

Ag1-Ag1A

2.8595(8)

N2-Ag1-N1

74.28(12)

P1-Ag1-N2

149.19(5)

P1-Ag1-N1

136.41(13)

P1-Ag1-Ag1A

113.85(13)

Symmetry transformations used to generate equivalent atoms: A -x, y, -z+1/2;

17

Figure 1 ORTEP diagram of complex 1 with ellipsoids shown at the 50% probability level. All hydrogen atoms are omitted for clarity.

18

Figure 2 ORTEP diagram of complex 2 with ellipsoids shown at the 50% probability level. All hydrogen atoms are omitted for clarity.

19

Figure 3 ORTEP diagram of complex 3 with ellipsoids shown at the 50% probability level. All hydrogen atoms are omitted for clarity.

20

Figure 4 ORTEP diagram of complex 5 with ellipsoids shown at the 50% probability level. All hydrogen atoms are omitted for clarity.

21

Figure 5 ORTEP diagram of complex 6 with ellipsoids shown at the 50% probability level. All hydrogen atoms are omitted for clarity.

22

Figure 6 Absorption and emission spectra of 1-4 in CH2Cl2

1.0

1ab 2ab 3ab

Normalized intensity

0.8

4ab 1em 2em

0.6

3em 4em 0.4

0.2

0.0 300

350

400

450

500

550

600

650

Wavelength (nm)

23

Graphic abstract (Pictogram) Five mononuclear copper(I) complexes and one dinuclear silver(I) phosphine complex containing the bispyridylpyrrole ligand were synthesized and structurally characterized.

N

N H

N

i) NaH, CuCl N

R

N

ii) 1 eq. Bis(phoshines) or 2 eq. PPh3

Cu

R

P

R

P

R = H, P^P = XANTPhos R = H, P^P = DPEPhos R = Br, P^P = XANTPhos R = Br, P^P = DPEPhos R = Br, P^P = 2 PPh3

N Br

N H

N

ii) 1 eq. DPEPhos Br

(1) (2) (3) (4) (5)

N

i) NaH, AgOTf N

R

N

Br

N Ag P

Ag

Br

P^P = DPEPhos

P 6

25




Five mono-nuclear copper(I) and one di-nuclear silver(I) phosphine complexes containing

bispyridylpyrrole

ligand

(PDP-)

are

synthesized

and

structural

characterization.


The use of a pincer-like PDP- as the anionic chelating bidentate ligand.




The solvent effect of these complexes on absorption and emission spectra are evident.

26