Electrophilic vinylations by vinyllead triacetates and tribenzoates generated by tin–lead exchange

Abstract

Trimethyl(vinyl)stannanes undergo a rapid tin–lead exchange with lead tetraacetate to give high yields of unstable vinyllead triacetates. Solutions of vinyllead triacetates produced in this way react with soft carbon nucleophiles such as β-dicarbonyl compounds and nitronate salts to give moderate to good yields of C-vinylated products. The method is more economical in terms of vinyl group incorporation than previously reported vinylations by vinyllead triacetates. An even faster tin–lead exchange has been observed when trimethyl(vinyl)stannanes are treated with lead tetrabenzoate, and vinylations with this reagent proceeded in significantly higher yields.