Novel alkylaluminium chloride promoted [2+2] cycloaddition reactions of styrenes with 1,4-naphthoquinones and bromoquinones: A facile route to orthoquinodimethane precursors

Article abstract of DOI:10.1016/S0040-4039(97)82974-7

The first examples of a Lewis acid catalysed [2+2]cycloaddition between styrenes and naphthoquinones have been observed. The reactions of both methoxyl and acetoxylnaphthoquinones were both regio- and stereospecific. When m-methoxystyrene was employed a novel tetracycle was also formed, and by an unexpected mechanistic pathway. Extension to bromoquinones resulted ultimately in the formation of arylnaphthocyclobutenes, common precursors of the orthoquinodimethanes.