Generation and dimerisation of 1,2-napthoquinone-1-methide

Abstract

The Diels–Alder reaction between two molecules of 1,2-naphthoquinone-1-methide (IV) yields 1′,2′-dihydrobenzo[f]chroman-2-spiro-1′-naphthalen-2′-one (V)(kinetically favoured) which rearranges irreversibly to 1′,2,2′,3-tetrahydro-4-hydroxyphenalene-1-spiro-1′-naphthalen-2′-one (VIII)(thermodynamically favoured); the ease of generation of 1,2-naphthoquinone-1-methide (IV) from the dimer (V) and its potential use in synthesis is described.