A Family of Routes to Substituted Phenols, Including Meta-Substituted Phenols

摘要

A new family of routes to substituted phenols has been developed. 2-Bromo-3-methoxycyclohex-2-en-1-ones are readily deprotonated at C-6, and the resulting anions, react smoothly with a variety of, elettrophiles; treatment with DBU in PhMe at room temperature then results in efficient aromatization to benzene derivatives of a regiochemically defined substitution pattern. This sequence afford S phenolic azides (ArN3), sulfides (ArSR, ArSAr'), selenides (ArSePh), alcohols [ArCH(OH)R], amino derivatives [ArCH(NHSO2Ar')R), and 1,2-benzenediols. A complementary set of substitution patterns is obtained by DIBAL-H reduction or reaction with a Grignard reagent before aromatization; the latter process gives compounds in which the newly introduced substituent is meta to the phenolic hydroxyl.