Md. Couce et al., SYNTHESIS AND CHARACTERIZATION OF ORGANOTIN COMPLEXES WITH 2-MERCAPTOPYRIDINE DERIVATIVES, Applied organometallic chemistry, 10(1), 1996, pp. 35-45
By reaction of diphenyltin(IV) chloride and triphenyltin(IV) hydroxide
with esters of the 2-mercaptopyridine-5-carboxylic acid NH(CS)CHCHC(C
OOR)CH (HTNME, R = methyl; HTNEE, R = ethyl; HTNIPE, R = isopropyl) th
e complexes Ph(3)Sn(L), Ph(2)SnCl(L) (L = TNME, TNEE and TNIPE) and Ph
(2)Sn(TNEE)(2) have been prepared and characterized by IR, NMR and Mos
sbauer spectroscopies. Moreover, the Ph(2)SnCl(2)/2-mercaptopyridine (
HMP) system has been found to yield either the Ph(2)SnCl(2)(HMP)(2) ad
duct or the Ph(2)SnCl(MP) complex. The structures of Ph(2)SnCl(TNEE) a
nd Ph(2)SnCl(MP) have been determined by X-ray single-crystal diffract
ion studies. The two structures are similar. Both ligands behave as bi
dentate chelating groups forming a four-membered ring with an identica
l small N-Sn-S bite angle of 63.7 degrees. The tin atom is pentacoordi
nated, presenting a severely distorted trigonal bipyramidal geometry w
ith apical Cl-Sn-N angles of 155.0(2)degrees [Ph(2)SnCl(TNEE)] and 155
.7(7)degrees [Ph(2)SnCl(MP)] and equatorial C-Sn-C angles of 114.9(2)d
egrees and 125.0(3)degrees respectively. On the basis of Sn-119 Mossba
uer data, all the complexes should present analogous structures except
Ph(2)Sn(TNEE)(2) and Ph(2)SnCl(2)(HMP)(2), for which an octahedral co
ordination geometry with a trans arrangement of the phenyl groups can
be proposed. The effect of dimethyl sulphoxide on Ph(2)SnCl(L) and Ph(
2)SnCl(2)(HMP)(2) is also discussed.