Synthesis of 2-(o-hydroxyphenyl)- and 2-(p-hydroxyphenyl)-2,5-dihydrofurans from o- and p-hydroxybenzylidene ketones and dimethylsulphonium methylide

Abstract

Dimethylsulphonium methylide reacts smoothly with o- and p-hydroxybenzylidene ketones giving moderate to high yields of 2-(o-hydroxyphenyl)- and 2-(p-hydroxyphenyl)-2,5-dihydrofurans, respectively; the easy formation of o- or p-quinone methide intermediates accounts for the unusual course of the methylene transfer reaction.