Mixed Diorganotin Oxides

Some new mixed oxides with aluminum, titanium, vanadium and zirconium appear in this chapter. Polymeric mixed oxides are listed in Section 8.1. The compounds summarized in Table 188 are prepared by the following methods. 

I Cohydrolysis of diorganotin dihalides in presence of ammonia with  

Bug S nO S 1.P ligO S IF h g AcO(i-Bu SnOSiMeg)gOEt PhgSn(OSiPhQ)2 (i 06) (PhgSn0H)2Si4Ph606 

Thermogravimetrlc analysis (958). (g) Use as vulcanization accelerator for polysiloxanes (195a)- (h) Biol, 

New in this chapter are a number of organotin alkoxide acetals and derivatives of organotin alkoxides with chelating 1,2- and 1,3 diketones. It is doubtful in most cases that the two different moieties are linked to the same tin atom. The compounds compiled in Tables I89 and I90 are prepared by methods from the following scheme. 

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Tetraorganodistannoxane 11 is in equilibrium with cycto-(f-Bu2SnO)3 (14) and the mixed diorganotin oxides cydo-R2Sn(OSnf-Bu2)20, (15, R = Me3SiCH2), and cycto-f-Bu2Sn(OSnR2)20 (16,... 

Scheme 2.10.5 Two pathways proposed to account for the formation of mixed diorganotin oxides 15 and 16...

Keywords Mixed Diorganotin / Diorganosilicon Oxide / Si NMR / " Sn NMR / X-Ray Analysis... 

The Sn CP MAS NMR chemical shift of 4 amounts to -232 ppm, which is 53.5 ppm to lower frequency in comparison with the solution chemical shift. We tentatively attribute this to different conformations in the solid state and in solution. To the best of our knowledge 3 and 4 represent the first completely characterized mixed diorganosilicon/diorganotin oxides. 

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