Tandem Silylformylation/Wittig Olefination of Terminal Alkynes: Stereoselective Synthesis of 2,4-Dienoic Esters

Abstract

The rhodium(I)-catalysed sequential silylformylation/Wittig olefination of terminal alkynes with hydrosilanes and carbon monoxide in the presence of stabilised P-ylides leads to substituted 2,4-dienoic esters in a one-pot procedure. The α,β,γ,δ-unsaturated esters are generated with high (2E,4Z) stereoselectivity in good to excellent yields. Conversions of the products in [2+1] cycloaddition reactions are presented.