Favorskii-Type Rearrangement of α,α'-Dihalo Ketones Induced by Enolates of (Diethoxyphosphynyl)acetic Esters and Its Application to the Synthesis of α,α'-Divinyl Ketones

Article abstract of DOI:10.1246/bcsj.60.1945

A Favorskii-type rearrangement of 1,3-dihalo-3-methyl-2-butanone with enolate of ethyl (diethoxyphosphinyl)acetate or t-butyl (diethoxyphosphinyl)acetate gave ethyl 2-(diethoxyphosphinyl)-5-methyl-3-oxo-4-hexenoate(3a) or its t-butyl ester (3b).Compound 3b was applied to the preparation of (E)-5-methyl-1-(p-tolyl)-1,4-hexadien-3-one and diethyl (4-methyl-2-oxo-3-pentenyl)phosphonate, which are the important intermediates for natural product syntheses.