The structural behaviour of 2,2-functionally disubstituted triorganotin chlorides

Abstract

A series of 13 2,2-difunctional triorganotin chlorides of the general formula Me 2(Cl)SnCH 2CH(XO)YO(XO, YO P(O)R 2, C(O)R; R  O iPr, OEt, Ph) has been synthesized by chlorination of the corresponding tetraorganotin compounds Me 3SnCH 2CH(XO)YO with HCl in diethyl ether. The crystal structure determination of Me 2(Cl)SnCH 2CH[P(O)(O iPr) 2] 2 (VIII), IR spectroscopic data and NMR studies reveal, for the title compounds, molecular structures in which the tin atom, approaches a trigonal-bipyramidal pentacoordinated ligand arrangement as result of an intramolecular Sn … O interaction of one of the two functional groups XO or YO respectively. In solution the compounds undergo a ligand exchange process which has been investigated by NMR. A mechanism of this process is suggested.