Selective Reduction of α,β-Unsaturated Weinreb Amides in the Presence of α,β-Unsaturated Esters

Abstract

α,β-Unsaturated esters were selectively protected in situ in the presence of α,β-unsaturated Weinreb amides using PEt₃ and trimethylsilyl trifluoromethanesulfonate (TMSOTf) in toluene under reflux. Diisobutylaluminium hydride (DIBAL-H) reduction of the mixture followed by tetra-n-butylammonium fluoride (TBAF) treatment produced α,β-unsaturated aldehydes in good yields along with the recovered α,β-unsaturated esters.

Keywords: chemoselective; in situ protection; reduction; α,β-unsaturated Weinreb amide; α,β-unsaturated ester.