Synthesis of Hydroxy-7H-benzo[c]fluoren-7-ones

Abstract
An efficient synthesis of 2-, 3- and 4-hydroxy-7H-benzo[c]fluoren-7-ones, useful intermediates for the synthesis of photochromic naphthopyrans, is described. The synthetic approach involves the use of oxazolines as activating groups for aromatic ­nucleophilic substitution and starts with readily available di­methoxynaphthaldehydes.