Syntheses of the natural dibenzofuran, ruscodibenzofuran

Short syntheses of the natural dibenzofuran, ruscodibenzofuran (1) from readily available phenols are described. The key steps involve initial formation of a 2-isopropenylbenzofuran by reaction of an ortho-halogenophenol with cuprous isopropenylacetylide followed by cycloaddition of methyl propiolate, to provide a functionalized dibenzofuran.