Iridium-catalysed asymmetric allylic alkylation of benzofuran γ-lactones followed by heteroaromatic Cope rearrangement: study of an unusual reaction sequence

Abstract

The iridium-catalysed asymmetric allylic alkylation of γ-lactones produces an all-carbon quaternary stereocentre substituted by an allyl and a benzofuran. The resulting 1,5-hexadienes were found to be excellent substrates for an unusual heteroaromatic Cope rearrangement. We describe here the first insight into the synthetic outcome of this intriguing reaction sequence.