Stannanes, tetrasubstituted

Such tetrasubstituted stannanes can then be readily converted into organic tin halides by a Kozeschkow disproportionation, thus 403... 

Reactions of potassium hypersilylchalcogenolates with SiCU, GeCU and SnCU yielded the tetrasubstituted silanes, germanes and stannanes despite four sterically demanding substituents (Eq. 3). The NMR data are summarized in Table 2. 

OSO2CF2) are also precursors of vinyl stannanes (155 X = SnBu )-The nucleophilic addition of the (trimethylstannyl)cuprates (156) and (157) to propiolamides can be controlled to give -(158) or -(158) selectively (Scheme 47). Tetrasubstituted vinyl-stannanes may be obtained by alkylation of the initial product of addition, a vinylcopper species (159). ... 

Catalyst in Oxidation Reactions. DBTO has been used as a catalyst in Fe -mediated oxidation of thiols to disulfides, even though Tri-n-butyl(methoxy)stannane seems to be better suited for this purpose. Epoxidation of terminal alkenes in a two-phase system (chloroform-water) containing H202/ammonium molyb-date/DBTO has also been reported. A combination of DBTO and t-Butyl Hydroperoxide oxidizes allylic alcohols with moderate regio- and stereoselectivity. Tri- and tetrasubstituted double bonds are most easily oxidized and the selectivities are comparable to those of the corresponding Vanadyl Bis(acetylacetonate) mediated reactions. 

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