Toward selective functionalisation of oligosilanes: borane-catalysed dehydrogenative coupling of silanes with thiols
Daniel J Harrison1, David R Edwards, Robert McDonald
1Department of Chemistry, University of Victoria, P.O. Box 3065, Victoria, British Columbia, Canada.
Abstract:
Among established methods for transforming Si-H bonds, carbonyl hydrosilylation and heterodehydrogenative coupling with alcohols catalysed by B(C6F5)3 are shown to provide exceptionally clean routes to the derivatisation of tetra-substituted disilanes such as [Ph2SiH]2, giving no products resulting from Si-Si bond cleavage. Even higher activity is observed for the borane-catalysed dehydrogenative coupling of silanes with alkyl- and arylthiols, the first examples of such Si-S bond formation in the absence of a transition metal catalyst. Clean, quantitative syntheses of a range of thiosilanes are reported, and the lability of the Si-S linkage toward subsequent alcoholysis is investigated. The crystal structure of 2,3-disila-2,2,3,3-tetramethyl-1,4-benzodioxane is presented.
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