Application of organolithium and related reagents in synthesis. Part 13. Synthetic strategies based on aromatic metallation. A concise regiospecific conversion of benzoic acids into 4-hydroxy-1-arylnaphthalenes

Article abstract of DOI:10.1016/S0040-4020(01)80334-3

The synthesis of the 3-unsubstituted phthalides (5) and their conversion into 1-hydroxy-1-arylphthalans (8), very useful precursors of isobenzofurans (10) and subsequent cycloaddition of them to dimethyl acetylenedicarboxylate as a way of regiospecific transformation of benzoic acids into dimethyl 4-hydroxy-1-(2-methoxyphenyl)naphthalene-2,3-dicarboxylates (12) (biaryls highly substituted around the axis), is described.