ON THE REACTION OF DIORGANODIHYDROXYSILANES WITH (T-BU2SNO)(3) - SYNTHESIS AND CHARACTERIZATION OF A NOVEL STANNASILOXANE COMPLEX AND ITS DISSOCIATION IN SOLUTION

The complex [Ph2Si(OSnt-Bu-2)(2)Ot-Bu2Sn(OH)(2)] (2) was obtained in h igh yield by reaction of Ph2Si(OH)(2) with (t-Bu2SnO)(3) (1). Reaction of t-Bu2Si(OH)(2) with 1 gave [t-Bu2Si(OSnt-Bu-2)(2)O] (4a) instead. The compounds were investigated by means of NMR, IR, Mossbauer spectro scopy, and in case of 2 by X-ray analysis. In solution, 2 is in equili brium with [Ph2Si(OSnt-Bu-2)(2)O] (2a), 1, and water. t-Bu2Sn(OH)(2) ( 3) was prepared by controlled hydrolysis of t-Bu2Sn(OMe)(2) and was sh own to undergo condensation with formation of 1. Mossbauer studies as well as Sn-119 CP MAS NMR including side band analysis suggest 3 to ex hibit a dimeric structure with pentacoordinate tin. Similar studies on 1 suggest fast rotation of the molecule in the crystal lattice.