abstract |
The invention relates to a process for the preparation of a phenolic hydroxy-substituted compound of the general formula (I) by desalkylation of an alkyl aryl ether of the general formula (II) by treatment with a thiourea/aluminum chloride reagent pair, in said general formulae R 1 stands for straight chain or branched C 1-6 alkyl group; R 2 , R 3 , R 4 , R 5 , and R 6 have the same or different meanings and stand for hydrogen or halogen atom, hydroxy, carboxy, nitro, oxo, C 1-6 alkylcarbonyl, straight chain or branched alkyl or -alkoxy, or aryl group, or R 2 and R 3 together stand for a 5-7 membered ring or fused ring system; said 5-7 membered ring may be a partially saturated ring optionally substituted with an oxo group or can be an unsaturated ring; or said fused ring system may constitute with the first ring a steroid, preferably an estratriene derivative optionally substituted with an oxo or C 1-6 alkylcarbonyloxy group in the 17 position. |