Efficient Alkenation of Aldehydes and Ketones to α,β-Unsaturated Esters Using α,α-Bis(dimethylsilyl)-substituted Esters

Abstract α,α-Bis(dimethylsilyl)-substituted esters 1 were found to be quite valuable for alkenation of various aldehydes and ketones to α,β-unsaturated esters. The reaction of aldehydes with 1 proceeded spontaneously in DMSO at 30 °C to give α,β-unsaturated esters with good to high E selectivity. Under the same conditions, ketones were insensitive to 1; however, Li2SO4 and CaCl2 effectively accelerated their alkenation.