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Synthesis and Characterizationof DI- and Triorganotin(IV)Compounds of 3-(2-Thienyl)-2-Propenoic AcidA. Badshah a , M. Danish a , Saqib Ali a , M. Mazhar a

, S. Mahmood a & M. Iqbal Chaudhry ba Department. of Chemistry , Quaid-i-AzamUniversity , Islamabad, Pakistanb Hussain Ebrahim Jamal (H. E. J.) Research Instituteof Chemistry , University of Karachi , Karachi,PakistanPublished online: 22 Aug 2006.

To cite this article: A. Badshah , M. Danish , Saqib Ali , M. Mazhar , S. Mahmood &M. Iqbal Chaudhry (1994) Synthesis and Characterization of DI- and Triorganotin(IV)Compounds of 3-(2-Thienyl)-2-Propenoic Acid, Synthesis and Reactivity in Inorganicand Metal-Organic Chemistry, 24:7, 1155-1166, DOI: 10.1080/00945719408001391

To link to this article: http://dx.doi.org/10.1080/00945719408001391

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SYNTH. REACT. INORG. MET.-ORG. CHEM., 24(7), 1155-1166 (1994)

SYNTHESIS AND CHARACTERIZATION OF DI- AND TRIORGANOTIN<IV>

COMPOUNDS OF 3-(2-THIE"fL>-2-PROPENOIC ACID

U A. Badshah. H. Danish, Saqib Ali. H. Hazhar and S . Hahmood

Dspnrt.ment. of Chemistry. Quaid-i-Azam Universitv. Islamabad, Pakistan

H. Iobal Chaudhrv Hussain Bbrahin Jamal (H.E.J.) Research Institute of Chemistry. University of Karachi. Karachi. Pakistan.

ABSTRACT

A series of oraanotin(1V) complexes of the general

formula R3SnL ( R = CH3. CZH5. "-C4H,. CeHll. CbH5) RzSnLz

prepared by treating the silver salt of 3-(2-thienyl)-Z-vro-

uenoic acid (2-thiouheneacrvlic acid) with the respective

tri- and diogranotin(1V) chlorides in (1:l) and ( 2 : l ) molar

ratio and characterized by elemental analyses. IR. 'H nmr and

mass spectrometry.

and

INTRODUCTION

The organotin comvlexes of thiovhene-2-carboxylic

acids and pyridine carboxylic acids are and were

found to be of distorted octahedral or trigonal bipyramidal

geometry. In the present paver trioganotin(1V) and

diorganotin(1V) complexes of 3-(2-thienyl)-2-propenoic acid

or 2-thiopheneacrvlic acid (I) were synthesised and

1155

Copyright Q 1994 by Marcel Dekker, Inc.

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1156 BADSHAH ET AL.

c h a r a c t e r i z e d f o r a s t u d y of t h e n a t u r e Of bondirlg and

s t r u c t u r e .

0 E L I I S CHZCH-C-OH

RESULTS AND DISCUSSION

The triorcanotin-2-thiophene a c r v l a t e s were p repa red

by r e f l u x i n g t h e s i lver salt of t h e o r g a n i c a c i d and

t r i o r g a n o t i n c h l o r i d e r l : 1 s t o i c h i o n e t r y . e q . c l ) l .

Dinethyltin-bis(2-thiopheneacrylate) was prepared from t h e

d i m e t h y l t i n d i c h l o r i d e and t h e s i lver s a l t of t h e a c i d

( 1 : 2 s t o i c h i o n e t r y ) , eq . ( 2 ) .

R3SnC1 + C7HsSCOOAa - C,H5SCOOSnR3 + A S 1

RZSnClz + 2C7HsSCOOAL1 - (C,H5SCOO)2SnR2 + 2AaC1

( 1 )

(R = Ke ( I a ) , E t ( I I Ia) . Bu ( I V a ) . Ph ( V a ) and Cy ( V I a )

( 2 )

R = K e ( I I b ) .

The s y n t h e s i s e d or&?anotins are s o l i d and s o l u b l e i n

n o s t of t h e o r g a n i c s o l v e n t s . The i d e n t i t y and s t r u c t u r a l

P r o p o s a l s of t h e complexes are confirmed by e l e m e n t a l

analysis, i n f r a r e d , ‘H nmr and m a s s spectral a n a l y s i s .

I n f r a r e d S p e c t r a

I n f r a r e d spectra have been r eco rded in t h e 4000-250

-1 cn range i n KBr d i s c s and impor t an t bands f o r s t r u c t u r e

ass ignments are g iven i n Tab le 1. C h a r a c t e r i s t i c v i b r a t i o n a l

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DI- AND TRIORGANOTIN(1V) COMPOUNDS 1157

Tab le 1. I n f r a r e d Data (cm-') for FC7HsSCOO14-nSnRn

Compound n R I ~ < C O O ) ~ ~ , , ~ lJ<COO)sym A v v(Sn-C) v(Sn-0)

Acid" - - 1677s 135011 327 - -

Acid-Agb - - 1632s 1332n 240 - -

Ia 3 H e 1629s 1386s 243 597m 486n

IIb '2 H e 1632s 1386b 246 600s 498s

IIIa 3 E t 1632s 1380s 252 594s 492m

I V a 3 Bu 1632s 1374n 258 600s 403m

V a 3 Ph 1629s 1392s 237 600m 486s

V I a 3 Cy 1638s 1371s 267 609b 489m

b aAcid = 3-(2-thienyl)-2-propenoic acid. Acid-Ag = s i l v e r

s a l t of a c i d . b = broad , m = medium, s = s t r o n g .

f r e q u e n c i e s have been i d e n t i f i e d by comparing t h e spectra of

t h e complexes w i t h t h e i r p r e c u r s o r s . The s i l v e r salt

fo rma t ion by t h e d e p r o t o n a t i o n of t h e c a r b o x y l i c a c i d group

is evidenced by t h e absence of t h e v<OH) band' a t 2890-2830

c m . The complexation of t i n ( 1 V ) w i t h t h e l i n a n d is

confirmed by t h e absence of Ag-0 and Sn-C1 v i b r a t i o n s at 535

and 333 CII-'. r e s p e c t i v e l y . whereas Peaks i n t h e range

483-498 cm-' i n d i c a t e t h e p re sence of Sn-0 bonds i n t h e s e

compounds.

-1

I n t e r e s t i n g f e a t u r e s are observed f o r c a r b o x y l a t e group

i n t e r a c t i o n s . A s r e p o r t e d i n t r i n e t h y l s i l y l

a c e t a t e which p o s s e s s e s a normal ester s t r u c t u r e , t h e

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1158 BADSHAH ET AL.

ca rbony l s t r e t c h i n g f r equency o c c u r s a t 1725 c m ? . The

cor responding a b s o r p t i o n f o r t r i n e t h y l t i n a c e t a t e is observed

a t 1576 c m ? which shows t h e a s s o c i a t e d t i n c a r b o x y l a t e s .

Based on t h e d i f f e r e n c e ( A v ) between v ( C 0 0 ) and

and t h e co r re spond ing band p o s i t i o n s , it is proposed t h a t t h e

c a r b o x y l a t e group is a c t i n g as a b i d e n t a t e c h e l a t e i n a l l

t h e s e complexes excep t i n V I a . which h a s a much larger v a l u e

and h e r e it p robab ly is a c t i n g as u n i d e n t a t e . having a

t e t r a h e d r a l a r rangement , wh i l e a l l o t h e r tri- and d i o r g a n o t i n

d e r i v a t i v e s have pen ta -coord ina ted t r i g o n a l b ipy ramida l and

weak hexa-coordinated o c t a h e d r a l geometry, r e s p e c t i v e l y

( F i g . 1).

- y m

* 'H Nuclear Magnetic Resonance Spec t roscopy

I19 Coupling c o n s t a n t s J( Sn'H) i n Hz a r e g iven i n I 1

0.58 p p m 158.31 s . 9 H,

1 H , 4-H; 7.15 epn C3.4

3 - H .

Compound Ia . 'H NHR (300 MHz. i n CDC13). 6'H [nJ<llPSn'H)Hzl:

Sn-CH3; 6 . 2 5 ppn 115.63. d ( b r o a d ) .

d . 1 H. 5-H; 7.32 ppn 15.71 d , 1 H,

Compound I I b . 'H N M R (400 MHz, i n CDC13), 6'H [nJ(llPSnlH)Hzl:

1.05 p p m C78.501 s, 6 H . Sn-CH3; 6.42 ppn C15.21, d c b r o a d ) ,

2 H ; 7.91 ppn C15.21, d ( b r o a d ) . 2 H; 7.02 pen C8.7; 3.61 dd ;

2 H ; 4 4 ; 7.27 ppm 13.61 d. 2 H . 5 4 ; 7.38 pen C51 d , 2 H, 3-H.

* s = s i n g l e t , d = d o u b l e t , t = t r i p l e t , dd = d o u b l e t of

d o u b l e t , n = n u l t i p l e t , 3-H. 4-H, 5-H are th iophene r i n g p r o t o n s .

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DI- AND TFUORGANOTIN(1V) COMPOUNDS 1159

S CH=CH-C

Fig. 1 (a) Triorganotin derivatives ( b) Diorganotin derivatives

Compound IIIa . 'H NHR I400 HHz. i n CDCJ ), 6'H [nJ(1'QSn1H)Hz3:

1.27 ppn C85 _+ 7; 25, 351 n, 15 H . Sn-C2H5; 6 . 3 ppm C15.63

dcbroad) , 1 H; 7.7 ppm C15.61. d(broad) . 1 H ; 7.02 ppm

C8.7; 3.61. dd, 1 H, 4-H; 7.19 ppn 13.61 d , 1 H . 5-H; '7.32

p p m C5.063 d, 1 H . 3-H.

Compound IVa. 'H NHR (60 HHz, i n CDC13). 6'H [nJ(l'QSniH)Hz~:

0.8 p p m 15.9. 35 ( H - H ) t , CH3; a complex p a t t e r n between 1.2

and 2 p p m is due t o coupling of (CH,CHz) p ro tons of methylene

group; 6.2 p p m rl5.81 dcbroad). 1 H ; 7.66 ppm LlS.81,

dcbroad). 1 H 6.8 - 7.3. n. 3 H .

Compound Va. 'H NtiR (60 HHz. i n CDCl.), 6'H CnJ<''eSn'H)Hz~:

6 .26 p p m C15.81, d(broad) 1 H ; a very complex p a t t e r n betueen

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1160 BADSHAH ET AL.

6.97 and 8.00 ppn is due t o t h e o v e r l a p of C6H5 - group

p r o t o n s and th iophene r i n g p r o t o n s .

Compound V I a . 'H NIIH (60 IIHz. i n C D C I J ) . S'H CnJ(llYSn'H)HzI:

complex p a t t e r n betwen 0.9 and 2 . 2 3 ppm is probab ly exp la ined

as CdHli - group p r o t o n s coupled w i t h e a c h o t h e r ; 6 . 2 ppm

115.83, d ( b r o a d ) , 1 H ; 7.36 p p m C15.81. d(b road) . 1 H ; 6 .8 -

7 . 2 ppm, m , 3 H .

From t h e v a l u e s of t h e coup l ing c o n s t a n t s ( S n - H e ) i t w a s

observed t h a t bo th t y p e s ( t r i - and d i o r g a n o t i n compoiinds of

2 - th iopheneac ry l i c a c i d ) a r e te t ra- and l i k e l y t o tJe w ~ a k

hexa-coordinated i i i s o l u t i o n , r e s p e c t i v e l y . T h e tcLt

coord ina ted t r i n e t h y l t i n ( 1 V ) conpourid has a l 2 . J 1 va lue

58 3 Hz having a n HP Sn He a n g l e of 111.16'. The o l e f i n i c

p r o t o n s (-CH = CH-) i n b o t h t y p e s of the compounds are t r a n s

t o each other*". The s u l p h u r of t h e r i n g does n o t c o o r d i n a t e

t o t i n (1V) .

1 0 11

Mass S p e c t r a

The scheme of p r o b a b l e f r agmen ta t ion p a t t e r n a t

80 e V . E . I . m a s s s p e c t r a fo r compounds Ia-VIa are g i v e n i n

Table 2 .

The molecular ion peak i n most orgar iometa l l ic

compounds is n o t observed'. We observed a s i m i l a r p a t t e r n

w i t h no II' i n t h e nass spec t rum f o r compound I a . I t

immediately l o o s e s a methyl redical t o g i v e m/z a t 303. The

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DI- AND TRIORGANOTIN(1V) COMPOUNDS 1161

Tab le 2 . R e l a t i v e Abundence of Common I o n s observed a t 80 eV

for t h e I n v e s t i g a t e d Compoundsa

Fragment ion R = H e R = E t R = p-Bu R = Ph K 7 C y

(Ia) (IIIa) ( I Y a ) __ ( V a ) (Via)

- - RJSn (COz )C6H3S+ 0.5 0.4 -

RZSn(COZ)C6H5S+ 10.6 100 100 3.1 46.1

RZSnC6H5S+ 9.2 28.6 2.9 1.7 0.2

SnCe H5 S+ 10.1 28.7 17.7 0.2 7.2

C6 H5 SCOOH+ 100 11.3 6.1 100 100

Cb H3 S+ 41.7 44.6 8.6 36.2 40.5

SnOH+ 47.9 65.4 27.3 41.6 67.7

SIlH+ 45.3 3.1 3.0 45.9 39.7

OFor compound ( I I b ) . t h e r e l a t i v e abundence of v a r i o u s i o n s

is as f o l l o w s : RzSn(COZ )zC,2HioS: ( n o t o b s e r v e d ) ,

RSn(COZ)PHIDS~ (9.9). RSn(COZ)CI2HloS: (3.1), RSnCIZHloS~

(3.7), C6H5SCOOHC (loo), SnC6H5S+ (42.1). C6Hj (36.8), SnOH'

(58.4), and SnH+ (47.8) .

fragment a t m/z = 229 w a s ob ta ined a f t e r l o o s i n g COP and CZHb

molecules from m/z 303 and f u r t h e r f r agmen t s of

CbH3SCOPH+ (154), C6H3S+ (103). C,H: ( 6 5 ) . SnOH (137) and

SnH+ (121) were o b t a i n e d . S i m i l a r l y , i n compound I I b R O

molecular i on peak was obained b u t a f t e r l o o s i n g a methyl

r a d i c a l , m/z 441 w a s observed which s u c c e s s i v e l y l o o s e s COz

t w i c e t o g i v e f ragments a t 397 and 353. The f ragment m/z 456

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1162 BADSHAH ET AL.

a l s o l o o s e s C7H5S02 t o y i e l d m / z 303 which f u r t h e r f o l l o a s

t h e s a m e p a t t e r n of f r a g m e n t a t i o n . Compound IIIa does n o t

y i e l d a molecular i on peak , b u t a f t e r l o o s i n g an e t h y l

r a d i c a l , m/z 331 is ob ta ined fo l lowed by t h e s u c c e s s i v e

e l emina t ion of COz and bu tane molecu le s t o g i v e m / z a t 287

and 229, r e s p e c t i v e l y . F u r t h e r f r agmen t s w e r e s i m i l a r t o t h a t

of compound ( I a ) and ( I I b ) . Compound ( I V a ) . ( V a ) and (Vla)

have a lmost t h e s a m e f ragment i o n s b u t d i f f e r e n t r e l a t i v e

i n t e n s i t i e s . The molecular i o n s are observed e x p e r i m e n t a l l y

f o r compounds ( IVa) and ( V a ) b u t n o t observed f o r compound

(VIa ) . I n a l l t h e s e compounds (Ia-VIa) peaks a t m / z 154 a r e

observed f o r Cali, S CO, H+ .

Chemicals

A l l compounds w e r e p repa red by u s i n g r e a g e n t s of 9 a n a l y t i c a l g r a d e , d r i e d s o l v e n t s and i n e r t a tmosphere ,

S y n t h e s i s of Conp l e x e s

2-Thiopheneacry l ic a c i d (15.4 8 . 0 . 1 mol) w a s

d i s s o l v e d i n 300 mL of e t h a n o l . Sodium b i c a r b o n a t e ( 8 . 4 g ,

0.1 mol) w a s d i s s o l v e d i n 60 mL of d i s t i l l e d w a t e r and w a s

added dropwise t o t h e e t h a n o l i c s o l u t i o n of

2 - th iopheneac ry l i c a c i d t o o b t a i n a clear s o l u t i o n . A s i l v e r

n i t r a t e (17.0 g , 0.1 mol) s o l u t i o n i n 40 mL of w a t e r w a s

added dropwise w i t h c o n s t a n t s t i r r i n g t o t h e above s o l u t i o n .

The wh i t e p r e c i p i t a t e s o b t a i n e d were f i l t e r e d under s u c t i o n .

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DI- AND TRIORGANOTIN(1V) COMPOUNDS 1163

T a b l e 3. P h y s i c a l Pa rame te r s of t h e I n v e s t i g a t e d Compounds

Compound/ tI.P.@C Y i e l d s Recrystaliz- Elementa l Conposi- E m p i r i c a l % a t i o n s o l v e n t % C t i o n Z H Formula (1:l) C a l ~ C a l .

(EXP) (Exp)

( I a ) 155- 157 85 Acetone/Et he r

1 "H f **2 SSn

( I I b ) 135- 136 80 Acetone/Ether

ci 2, GO* s, Sn

( I I Ia ) 112-113 78 Acetone/Ether

Ct3H200ZSSn

( I V a ) 59- 61 65 CHZCIZ /E the r

C19H3302SSn

( V a ) 129 82 Chloroform

cz 5 H, 0 0, SSn

( I V a ) 78- 79 78 Chloroform

'2 5 H3 B ' 2 SSn

37.9

(37.37)

42.2 (41 - 98)

43.5

(43.20 )

51.6 (51.12)

59.6 (59-41)

57.58 (57.20)

4 . 4

(4 .39)

3.5 (3 .54)

5.57

(5.66)

7 .01

(7.36)

3.97 (3.61)

7.29 (7.70)

The p r e c i p i t a t e s w e r e t ho rough ly washed w i t h e t h a n o l and

d r i e d ove r P,05 i n t h e d a r k .

0.261 g (0.001 mole) of s i l v e r s a l t of 2-thiophene-

acry l ic a c i d w a s r e f l u x e d w i t h 0.386 g (0.001 mole) of

t r i p h e n y l t i n c h l o r i d e i n 150 mL of d r y ch loroform f o r 7-8

hour s under i n e r t atmosphere. While o t h e r 1:l and 2 : l

complexes were p repa red by r e f l u x i n g t h e s i l v e r s a l t of

2 - t h i o p h e n e a c r y l i c a c i d (0.261 g. 0.001 mol f o r 1:l and

0.522 g , 0.002 no1 f o r 2 : l ) w i t h 0.001 mol of t r i - o r

d i o r g a n o t i n c h l o r i d e s i n 150 mL of d r y ch loroform f o r 7-8

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1164 BADSHAH ET AL

hours under an i n e r t a tmosphere . A f t e r c o o l i n g t h e r e a c t i o n

mix tu re t o room t empera tu re . s i l v e r c h l o r i d e w a s f i l t e r e d and

t h e f i l t r a t e w a s c o n c e n t r a t e d for c r y s t a l l i z a t i o n .

P h y s i c a l measurements

The p h y s i c a l p a r a m e t e r s , s u c h as e l e m e n t a l a n a l y s e s

m e l t i n g p o i n t s and r e c r y s t a l l i z a t i o n s o l v e n t s o f t h e

i n v e s t i g a t e d compounds a r e g iven i n T a b l e 3. I n f r a r e d and

m a s s s p e c t r a were o b t a i n e d u s i n g a H i t a c h i Hodel 270-50

I n f r a r e d S p e c t r o p h o t o n e t e r and HAT 112 S Mass Spec t romete r .

N H R s p e c t r a were r eco rded i n CDC13 u s i n g Bruker SF 300, SF

400 UHz, 270 HHz and J e o l JNH-PHX 60 HHz s p e c t r o m e t e r s .

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Received: 10 December 1992 Referee 1: R. A. Geanangel Accepted: 7 April 1994 Referee 11: K. Moedritzer

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