GB1413078A — Process for the production of plus-norfenfluramine and plus-fenfluramine and salts thereof

USPTO Abstract

1413078 (+ )-Norfenfluramine BEECHAM GROUP Ltd 18 July 1974 [27 July 1973] 35924/73 Heading C2C (+ )-Norfenfluramine or a salt thereof may be prepared hydrogenating the novel compound of Formula (I) or a salt thereof: where R is a phenyl group, optionally substituted in the meta- or para-positions by a non- reactive group that does not interfere with the hydrogenation, the carbon atom marked with one asterisk has the same configuration as ( + )- norfenfluramine and the carbon atom marked. with two asterisks has the configuration found in (-)-α-methylbenzylamine. The compound of Formula (I) may be prepared by reducing a compound of Formula (II) or a salt thereof: which may itself be prepared by reacting 1-(m. trifluoromethylphenyl)propan-2-one with (-)- α-methylbenzylamine. (+ )-Fenfluramine may be prepared by the acetylation of (+)-norfenfluramine in conventional manner followed by reduction of the acetyl group to an ethyl group.