Hydrolyses of dimethylchlorotin carboxylates

271

&xwnaI of Organometallic Chemistry Elsevier Sequoia S-A., Lausanne - Printed in The Netherlands

HYDROLYSES

OF DIMETHYLCHLOROTIN

CHARLENE SHIBW-CHYN

CARBOXYLATES

WANG and JEANTQE M. SHREEVE

Department of Chemistry, University of Idaho, Moscow, Idaho 83843(U.S.A.) (Received June 2nd, 1972)

SUMMARY

The controlled hydrolyses of dimethylchlorotin ing to the following scheme :

R=CH&l,CHC12,CH2Br, CO as solvent.

carboxylates

proceed accord-

CH,I,CC1,,CF,,C2F,,C3F,,CF,Cl;S=H,0/(CH3)2-

INTRODUCTION

Partial hydrolyses of dimethylchlorotin carboxylates (CH,),Sn(Cl)O+CR CHJ resulted in the respective tetramethyl-l,3-dichlorodistannoxanes’-3. In an extension of these early hydrolysis studies, we have found that when R becomes more electron withdrawing (halogen-containing), tetramethyl-1,3_dicarboxydistannoxanes are the intermediate products, e.g., where R=CH,Cl, CHCll, Ccl,. CH,Br, CH,I, CFJ.C2F5.C3F,. and CF,CL The yields are high and there is no evidence for the formation of the 1.3-dichloro compounds. The addition of small amounts of water to solutions of (CH,),Sn(Cl)O,CR in pyridine gives rise to tetramethyl-lcarboxy-3-hydroxydistannoxanes in essentially quantitative yield. Under sufficiently alkaline conditions, the dimethylchlorotin carboxylates, 1,3_dicarboxydistannoxanes or l-carboxy-3-hydroxydistannoxanes are converted to dimethyltin oxide. The structures of these new compounds are deduced, primarily through the use of infrared spectra and elemental analyses and based on results in the literature. . (R=H,

EX’ERIMENTAL

Starting materials Dimethylchlorotin J. Qrganometai. Gem., 46

(1972)

carboxylates

were prepared by the literature method4. (continued on p. 274)

Hydrolysis

0

Cl 0 (CH&O&,F,

?I :: (CN,),SnOCCF,

(CH$nO&,

Cl 9

(CH,)18"Ok-m,

Cl 0

(CH&&"O&H,I

Cl 0

WW,SnOCW,I,O

::

::

[(CH3),SnOCCFJ20

[(CHJ),SnOCCCIJ20

e

:: [(CH,),SnOCCHCI,],

:: [(CHJ),,SnOCCH,lJ,O

F' :: (CH,),SnOCCH,Br [(CH,),S"&H,B~],O

(CH,)&OiCH,CI

Cl 0

(CH,),SnqCCH,

7’ ::

Starting

compound

N

> 360”

174-176’

16.90 2.50 (16.88) (2.48)

244-246’

14.39 2.26 171-172 (14.06) (2.36)

16.64 2.80 (16.30) (2.74)

18.75 3,03 230&0.5d (19.20) (3.22)

c

C

#4rlalysisa~l*rld M.p.b (calcd) ( X) ec, ---

80

90

17.95 2.33 (17.81) (2.24)

253-255 (dcc.)

232-233

90-9515.11 1.91 222-224O (15.05) (1.90)

96

90

75

- 90

-100

A

A

Yield (74

Mctlrod

PREPARATIONANDELEMENTALANALYSESOFDISTANNOXANESANDHYDROXYDISTANNOXANES

TABLEI

100 100

100 100

100 80-100

100 100

100 100

100

E(NHJ D(NHJ

100 100

3 2 i%

ir

“3 ?

3

P r cl

Yield ("/u)

E(NI-I,) 100 63-100 D

E(NH,) D

E(NHd D

D

UW,

&H,,

DPW

M&d

(CH,)JuO

13 id

7’ Y C

fl C,F,COSn(CH,),0Sn(CH3)20H

CH,Cl~OSn(CH,),OSn(CH,),OH

0

Y C2F5COSn(CH,),0Sn(CIJ~OH

CF,CI~OSn(CH,),OSn(CH,),OH

C

C

C

C

:: CCIJCOSn(CH,),OSn(CH,),OH

0

C

7 CF3COSn(CH,),0Sn(CH,),0Hh

-100

-100

-100

-100

-100

-100

82

16.02 2.82 (I 5.65) (2.82)

17073 2.45 (17.66) (2.39)

14.67 2.44 (14.61) (2,63)

16.45 2.62 (16.24) (2.93)

20.52 1.74 (19.49) (1.64)

>300”

198-199

241 (dcc,)

222-223

194-195

E

W-b)

W-b)

D

WNH,)

100 100

100

loo

100

a Analyses by Bellcr, Mikroanalytisches Laboratorium, GGttingen, Gumany or Glare Sicland, University of Idaho. h Thomas-Hoover capillary melting point apparatus, c IR, see ref. 35, 36. d 226-227, see rel 15.e 172-174, see ref. 15. / 232-233, see ref. 15. R221-222,see ref, 15.IrAlso prepared from hydrolysis of (CII,),Sn(Cl)O&(CF& (CH&NH.

7’ Y (CH&Sn~CCH$I

(CH,),inO&,F,

Cl 0

(CH,),;nO&F,Cl

Cl 0

(CH&SnOCC,F,

B

::

l$~WnOCC3%0

274

C. S.-C. WANG,

J. M. SHREEVE

Preparation of tetramethyl-1,3-bis(haloacetoxy)distannoxanes Method A. All of these compounds were prepared from the dimethylchlorotin carboxylates by essentially the same technique. To a solution of dimethylchlorotin chloroacetate (0.22 mmol) in acetone (5 ml), a few drops (2-3) of distilled water were added. A white precipitate formed with stirring, was washed with acetone which contained a trace of water until the filtrate gave no precipitate with silver nitrate solution and was then air dried. Method B. Same as Method A with 2 or 3 drops of 6 N NaOH to ensure complete hydrolysis. Preparation of tetramethyl-1-carboxy-3-hydroxydistannoxanes Method C. 1 mmol of a dimethylchlorotin carboxylate was dissolved in approximately 1 ml of pyridine. A few drops of distilled water were added ; a white solid formed, was filtered, washed with water and dried. Yields ranged between 9.5-100 %. Preparation of(CH&SnO Method D. Hydrolysis of(CH,),Sn(CI)02CR. This is MethodA but concentrated (12 N) NaOH was used in addition to distilled water. Method E. Hydrolysis of RC0,Sn(CH,),0Sn(CH,)202CR (or RCO,Sn(CH<n(CH&lN). This is Method D applied to the distannoxane or hydroxydistannoxane. I@ared

spectra Infrared spectra were recorded with a Perkin-Elmer Model 621 spectrometer_ Spectra were calibrated from known peaks of a polystyrene film. Spectra of solids were obtained with pressed KBr discs or Nujol mulls. Spectra of approximately 0.2 M solutions in CHCI, or CH2CI, were recorded using compensated KBr cells. All new compounds, method used, y0 yield, elemental analyses and melting point data are recorded in Table 1. RESULTS

AND

DISCUSSION

Preparation The initial hydrolysis products of the compounds R,Sn(Cl)O,CR’ might be expected to be R,SnX( OH) (X = Cl or 0,CR’). Existence of R,SnCl( OH) in solution has been confirmed5 but a compound has never been isolated. However, the only known examples of this type of compound are dialkyltin hydroxide nitrates6 which were isolated from the reactions of dialkyltin oxides with nitric acid. These are stable, high-melting crystalline substances which are resistant to condensations to give distannoxanes. The dimeric Ph,Sn,(NCO),(OH),’ was also claimed to have been isolated but it is a highly reactive intermediate. Just as the hydrolyses of dialkyltin dihalides and of dialkyltin dicarboxylates led to distannoxanes so the first isolated hydroiysis products from dimethylchlorotm carboxylates are [(CH3)&XJ,0 (X=Cl or O&R’) formed via intermolecular dehydration of the probably unisolable intermediate, (CH,),SnX(OH). However, all previous reports1-3*8-10 of the partial hydrolysis of R,Sn(X)O,CR’ invariably identify (R,SnX),O (X=halogen) as the product with no (R;SnO,CR’),O isolated. J. Organomerd.

Chm,.,

46 (1972)

HYDROLYSES

OF DIMETHYLCHLOROTIN

275

CARBOXYIATES

Hydrolyses of a series of compounds, R&XY (X, Y = halogen or carboxylate), in the presence of amines, show that the ease of removal decreases from X = OAc, I > Br > Cl > F**‘, e.g., 2 (C,H,),SnCIF

+ Hz0 -

[(C4~,)$n~],~

+ 2 HCI

In our series of compounds, (CH&Sn(CI)O,CR, only in the case where R=CH, is the dichlorodistannoxane, [(CH,),SnCl],O, obtained’*‘. With all others, where R= CH,CI, CHCl,, CCIJ, CH2Br, CH,I, CF,, C,F,, C,F,, CF,Cl, the dicarboxydistannoxanes [(CH,),SnO,CR],O are invariably isolated_ This synthetic route has not been reported previously. Tetraalkyl-1,3-dicarboxydistannoxanes have resulted from partial hydrolyses of diorganotin dicarboxylates, reactions of diorganotm oxides with carboxylic acids or anhydrides, and organotin dihalides with organic acid salts1V2*g-27. The method described here is simple and fast. Addition of distilled water to an acetone solution of the dimethylchlorotin carboxylate followed by stirring for a few minutes at 250 (a small amount of aqueous NaOH is required for the fluorocarboxylates) resulted in the precipitation of distannoxanes in high yields. Several new as well as previously known tetramethyl-1,3-dicarboxydistannoxanes were synthesized via this route (Table 1). These compounds are very stable in water and in moderately basic solutions, e.g., aqueous NaOH (pH - 8-9) or pyridine. Evaporation of a water/ acetone solution of the distannoxanes leaves the white solid unscathed. The fluoroacetate compounds are readily soluble in acetone but the others are not. It has been shown that stable products in the hydrolyses of R,SnX, (X = halogen or carboxylate) are obtained in the following sequence 10*2g_ OH-

R2SnX2 -

OH-

(R2Sn2X2) 0 --+

CR4Sn2JWWl 0 (1)

&SnOL. (11)

We have been able to isolate the compound (I) of our system (CH,),Sn(02CR)OSn(OH)(CH,), by dissolving (CHs),SnCl(O,CR) in pyridine and then adding water. It was possible to isolate the hydroxy distannoxanes only when R=CF,, C,F,, C,F,, CF,CI, CHzCl or Ccl, (Table 1). However, all attempts to obtain the hydroxy distannoxanes from the dicarboxydistannoxanes resulted either in recovery of starting material or complete hydrolysis to dimethyltin oxide. Other workers have been able to prepare (AcO)R,SnOSnR,OH from [R,Sn(OAc)],O when R=C2HS, C,H,, C,H,, etcz2 and XR,SnOSnR,OH from (R2XSn),0 (X= haIogen)g*10*30_ The final product (II) from exhaustive hydrolysis of the dimethylchlorotin or RCOz(CH3),SnOSn(CH,),0H is carboxylates or from [(CH&SnO,CR],O the very insoluble (CH,),SnO when concentrated solutions of NaOH or NH, are used. Inji-ared Many compounds of the type XR,SnOSnR,Y are known, with X and Y as halogen, pseudohalogen, carboxylate, nitrate, isothiocyanate, alkoxide or phenoxide r2. Interest in these compounds lies in their dimeric structures, based on a 4-membered (Sn-0), ring in which the tin atoms are pentacoordinate12*28’30’32. The structure has been proposed as shown in the following in which both penta- and tetracoordinate tin atoms are present (III). If the substituent X is a coordinating group, such as OH-, J.

Organometa~.

Gem.,

46 (1972)

z

5

1418 s 1398(sh) 1334 m

CO2 sym. stretch and CHJ deformation

SnO

--

300 s

Sn-0-Sn stretch and COz out-of-plane SnC2 asym. stretch SnCz sym. stretch SnO ring and CO, rock

” See ref. 22.

666 s 656 s 623 (sh) 610s 579 m 530 s 505 s 493 (sh)

CH,(-Sn) rock CO2 scissor

1560s

Solid

CH,”

CO2 asym. stretch

R

1667s 1419s

1.562s 1426 s 1378 s 1319 s

583 m 525 (sh) 507 s 480 m 440 w 273 m

575 s 525 m 505 s 481 (sh) 278 s

635 s

645s

787 s 680 m

1343 s

1676 s

1630 s 1605 m

CHC13

CHJl

582(sh) 525 (sh) 497 s 450 w 473 w 285 m

620 s

790 s

1620s 1415(sh) 1490s 1350s

1665 s

CHClz

587 s 527 m 501 s 44ow 280 s

587 m 530 m 510 s 445 m 215 s

583 m 524 m 502 s 480 (sh) 445 w 285 m

623 s

790 s 668 s

1580s 1420s 1380 s

CHJ

636 s

790 s 678 m

1602s 1419 s 1400(sh) 1325 s

1676s

CH2Br

625 s

1640s 1405 m 1375(sh) 1363 s 1309s 788 m 680 s

1683s

CC/j

RELEVANT INFRARED VIBRATIONAL FREQUENCIES (cm-‘) OF SOLID [(CHS)zSnO,CR]zO

; $

6

TABLE 2

R c

9 ii

2

0

5

460 w 290 m

590 m 525 (sh) 499 s

629 s

793 s

1658s 1464 m 1420 m

1700 s

CF3

430 w

500 s

590 m

620 m

795 s

430 w 290 m

590 m 530 w 499 s

625 s

795 s

1650s

1663 s 1438 w 1388 w 1338m 1655s 1438w 1388w 1330s

430 w 285m

585~ 525 w 504 s

628 s

790 s

1430 s 1380 s

1695 s

CF,CI

1700s

C,F7

1693s

Ws

3

; m

$ _$I ?

p r 0 <

2 a?

HYDROLYSES

OF DIMETHYLCHLOROTIN

NCS-. OCH;, there are additional weak intramolecuIar which give rise to a Iadder type structure.

on) i

277

CARBOXYLATES coordinations

as in (IV)

m?)

The dimeric ladder type structure of R’CO&R,OSnR,O,CR as (IV) in the solid state or in moderately concentrated solutions has been supported by infrared”, ’ “Sn MSssbauer33*34, ’ rgSn N’MR34, molecular weightg, and X-ray31*3g*40 studies. The structure of the series of distannoxanes investigated here has no reason to be an exception_ In the infrared spectra, the positions of relevant absorption bands and their assignments, made by referring to the spectrum of [(CH3C02)(CH3),Sn)20]22*35 are listed in Table 2. The compounds [(AcO)R,Sn],O (R=CH3, C2H,, n-C,F,, n-C,H,) have been considered to be dimeric at moderate concentrations and to dissociate to monomers in dilute benzene and chloroform solutionsz2. The infrared spectra of these compounds change in the COZ asymmetric stretching region with change in state. However, the compounds RC0,Sn(CH3)20Sn(CH3)202CR (R= CH,Cl, CHCI,, Ccl,. CH213r, CF,, C2F5, C3F7, CF,Cl) show two CO, asymmetric bands in the solid state and in CH,C12 or CHC13 solution (- 0.2 M) (Table 3). The very broad singIe CO, band in [(CH21C0zSn(CH3),],0 in solid state splits into two bands in CH,Cl, solution. No additional COz asymmetric stretching bands appeared in soIutions of the compounds and the CO, asymmetric stretching frequencies of the tetramethyldistannoxanes are essentially constant in both solid state and in solution which may be explained by the presence of the same configuration in both states. From the values of C-O stretching frequencies, the RCOz groups are not of the ester type and must act as chelate or bridging groups. For comparison, the v,(CO,) values for RCO,Sn(CI)(CH,), are also listed in Table 3. These are in the range expected for v,(CO,) in a bridging RC02 group in the sohd state. The intensities of two v,(CO,) frequencies differ with the one at lower energy being more intense. It is noted in the fluorocarboxy distannoxanes that the band at higher energy is close to the v,(CO,) frequencies in (CH3)$n(CI)02CR with the exception of the C,F, compound. In the other halo-substituted acetoxy distannoxanes, the band at higher energy occurs higher than in the chlorotin carboxylates. However, the high frequency one is closer to the v(COJ frequency of RCO,Sn(Cl)(CH,), in solution. Davies et 01.~~ explained the infrared spectra of [CH,C(O)-0-Sn(C,H,),-],O by assigning the two carbonyl absorptions at 1560 and 1418 cm-l to a symmetrical (bridging) carboxylate group, and the two bands at 1630 and 1362 cm-’ to a non-bridging group._Therefore, the lower irequency RCO, stretch of the tetramethyldistannoxanes must be due to the absorption of bridging carboxylate groups. All of the tetramethyldistannoxanes show a strong band near 600 cm- 1 J. OrgnnometaI. Chem., 46 (1972)

C. S-C. WANG, J. M. SHREEVE

278 TABLE

3

v,(COz)(cm-‘) XANES

FOR

R

(CH,),Sn(Cl)OJR

C~:(CH,LSnWW,O

(CHS),Sn(O,CR)OSn(CH,),(OH)

-3

1691” 1692b i696” 169ob 1655” 16Ub 1688” 168ob 1598“

1700,165s 17i2, 1657b 1693,165s 1700. f655b 1700,1663 1700,165ob 1690,165O 1713,16&P 1676,1607 1650,160@ 1665, 1623 l660,16206 1683,164O 1687, 1642b

167s

GF, GF, CF,Cl CH&I

CHCI, ccl,

CH,Br CHJ CH,’

TIN

CARBOXYLATES,

1635b 1624” 1643b 1635= 165@

1590” 162ob 1550” 16lob 1.550”

o Solid. b In CH,Cl,

or CHCl,

DISTANNOXANES

AND

HYDROXYDISTANNO-

1678 1681 1676 1617

1665

1676.1602

1580v(br) 1610,ISSOb 1580 solution.

c Ret 3.

TABLE 4 RELEVANT INFRARED VIBRATIONAL FREQUENCIES (cm- ‘) OF (RC0,)(CH,)2SnOSn(CH3)2(0H)

OH stretch CO, CO, CH,

asym. stretch. sym. stretch and deformation

CH, (-Sn) rock SnOSn stretch and SnC, asym. stretch SnCz sym. stretch

CHzCl

ccl,

CF,

C,F,

CJ,

CCIF,

3400 s (br) 1615 s 1405 (sh) 1390 m 1360 m 780 s 590-570 s (br)

3400 s (br) 1665 s 1383 (sh)

3400 s (br) 1678 s 1434 ms

3440 s (br) 1678 s 1405 m

3440 s (br) 1681 s 1401 m

3400 1665 1405 1390

1335 s 780 m 570 s (br)

790 s 570 s (br)

1325 m 775 m (br) 560-540 s (br)

1335 m 770 m 570 s (br)

520 w (sh) 47s w

CO2 rock sno

ring

418 w

SnO

418 w 380 w

525 m 462 m 410m 380 w 280 m

s (br) s (sh) m

775 m 580-540

530 (sh) 490m

530 (sh) 495 m

528 (sh)

383 w 285 w

382 m

285 w

(Table 2) which is the characteristic Sn-0-Sn stretching vibration in the dimeric structureg*22.30*36-38_ Therefore, all of the carboxydistannoxanes very likely do have the central ladder structure of (IV) although it wouId be interesting to Ieam about the type of coordination exhibited by the non-bridging RCO, groups. X-ray structure determinations would be very helpful in solving this question. J_Organomeful. Chem,46 (1972)

s (br)

HYDROLYSES

OF DIMETHYLCHLOROTIN

CARBOXYLATES

279

The refevant absorptions for RCO,Sn(CH,),OSn(CHs),OH are listed in Table 4. The OH stretching vibrations appear around 3400 cm- ’ and Sn-0-Sn stretching bands around 600 cm -I_ The compounds show one kind of .v,(COz) absorption in the infrared spectra. The position of v,(CO,) absorption is intermediate to those found for the 1,3-dicarboxydistannoxanes which suggests either bridging or chelating RCO, groups. ACKNOWLEDGEMENTS

Fluorine research at the University of Idaho is suppoerted by the Office of Naval Research and the National Science Foundation, J. M. S. is an Alfred P. SIoan Foundation Fellow. REFERENCES 1 R. Okawara and E. G. Rochow. J. Amer. Clzem. Sot., 82 (1960) 3285. 2 R. Okawara and E. G. Rochow, U.S. Dept. Corn., Ofice Tech. Seru.: PB Rept. 17i, 571(1960) 12; Chem. Abstr., 58 (1963) 3454 h. 3 M. Wada, M. Shindo, and R Okawara, J. Orgonometal. Clzem., 1(1963) 95. 4 C. S. Wang and _l. M. Shreeve, 3. Organometal. Chem., 38 (1972) 287. 5 K. Yasuda H. Matsumoto, and R. Okawara, J. Organometal. Chem., 6 (1966) 528. 6 K. Yasuda and R. Okawara, J. Orgarzometol. Chem., 3 (1965) 76. 7 A. S. Mufti and R. C. Poller, J. Chem. SW., (1965) 5055. 8 D. L. Alleston and A. G. Davies, J. Chem. Sot., (1962) 2050. 9 D. L. Alleston, A. G. Davies, M. Hancock, and R. F. M. White, J. Chrm. Sot., (1963) 5469. 10 D. L. Alleston, A. G. Davies, and M. Hancock, J. Chem. Sot., (1964) 5744. 11 R. W. Weiss, Organometallic Compozcnds, Vol. II, Springer-Verla, 0 New York, 2nd ed., 1967, p. 433 and references therein. 12 R. Okawara and M. Wada, A&an. Organomeral. Chem, 5 (1967) 137, and references therein. 13 T. Harada, Sci. Papers Inst. Phys. Chem. Res., Tokyo, 57 (1963) 25; Chem. Abstr., 59 (1963) 7550 g. I4 N. S. Vyazankin, G. A. Razuvaev, 0. A. Kruglaya-Shchepetkova, and 0. 5. D’yachkovskaya, Akod. Nauk SSSR, Inst. Obshch. i Neorgan. Khim., (1963) 298; Chem. Abstr.. 60 (1964) 1204Od. 15 M. Ohara, R Okawara and Y. Nakamura, Bull. Chem. Sot. Jup., 38 (1965) 1379. 16 D. L. Alleston and A. G. Davies, Chem. I&. (London), (1961) 949. 17 N. S. Vyazankin, G. A. Razuvaev, 0. S. D’yachkovskaya, and 0. A. Shchepetkova, Dokf. &cd. Nonk SSSR, 143 (1962) 1348. 18 M. Frankel, 0. Wagner, D. Gertner, and A. Zilkha, Israel J. Chem., 6 (1968) 817. 19 K. A. Kocheshkov, E. M. Panov, and N. N. Zemlyanskii, lzu. Akad. SSSR, Otd. Kim. Nauk, (1961) 20 21 22 23

24 25

26 27

28 29

30 31

32 33

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J. OrganometaL Chem., 46 (1972)

280 34 35 36 37 38 39 40

C. S.-C. WANG, J. M. SHREEVE

A. G. Davies, L. Smith, P. J. Smith, and W. McFarlane, J_ Organometaf. Chem., 29 (1971) 245. R. Okawara, D. E. Webster, and E. G. Rochow, J. Amer. Chem. SW., 82 (1960) 3287. M. P. Brown. R. Okawara, and E. G. Rochow, Sgectrochim. Acta, 16 (1960) 595. R. Okawara and M. Wada, J_ Organometd. Chem., 1 (l963) 47. M. Wada, M. Nishino, and R. Okawara, J. OrganometaZ. Chem., 3 (1965) 70. Y. M. Chow, Inorg. Chem., 10 (1971) 673. H. Matsuda, F. Mori, A. Kashiwa, S. Matsuda, N. Kasai, and K. Jitsumori, J. Organometal- Chem, 34 (1972) 341.

J. Organometaf. Chem., 46 (1972)