(1) Ets. CLIN-MIDY, F-91301 Massy, Frankreich;(2) Institut für Organische Chemie, Universität Mainz, D-6500 Mainz, Bundesrepublik Deutschland
Abstract:
TheFries rearrangement of different methoxy benzoates has been investigated. Frompara-methoxy benzoates the corresponding hydroxy-4-methoxy benzophenones could be obtained in good yields by treatment withLewis acids (especially TiCl4) in nitromethane at 20°C (4-hydroxy derivatives) or without solvent at 120°C (2-hydroxy derivatives). Under the same conditions only demethylation occurs withortho-methoxy benzoates leading to the corresponding salicylates. Small amounts of hydroxy-2-methoxy benzophenones were obtained by treatment with polyphosphoric acid.