[EN] OPTICALLY ACTIVE 1-(FLUORO-,TRIFLUOROMETHYL-OR TRIFLUOROMETHOXY-SUBSTITUTED PHENYL)ALKYLAMINE N-MONOALKYL DERIVATIVES AND PROCESS FOR PRODUCING SAME [FR] DERIVES DE 1-( PHENYLE A SUBSTITUTION FLUORO,TRIFLUOROMETHYLE OU TRIFLUOROMETHOXY)ALKYLAMINE N-MONOALKYLE OPTIQUEMENT ACTIFS ET LEUR PROCEDE DE PRODUCTION
Process for producing optically active 1-(fluoro- or trifluoromethyl-substituted phenyl) ethylamine and process for purifying same
申请人:Central Glass Company, Limited
公开号:US06797842B2
公开(公告)日:2004-09-28
An optically active 1-(fluoro- or trifluoromethyl-substituted phenyl)ethylamine is produced with high optical purity and in an industrially simple and efficient manner by asymmetrically reducing an optically active imine, obtained by dehydration and condensation of a fluoro- or trifluoromethyl-substituted phenylmethyl ketone and an optically active primary amine under acidic conditions, using a hydride reducing agent to convert to an optically active secondary amine, and subjecting the secondary amine or its salt of an inorganic acid or organic acid to hydrogenolysis. In addition, an optically active 1-(fluoro- or trifluoromethyl-substituted phenyl)ethylamine is purified to an even higher optical purity in an industrially simple and efficient manner by converting the optically active secondary amine of the synthetic intermediate obtained by asymmetric reduction, or an optically active 1-(3,5-bis-trifluoromethylphenyl)ethylamine, one of the target compounds, to an inorganic or organic acid salt followed by recrystallization purification. This ethylamine is an important intermediate of pharmaceuticals and agricultural chemicals.
[EN] OPTICALLY ACTIVE 1-(FLUORO-,TRIFLUOROMETHYL-OR TRIFLUOROMETHOXY-SUBSTITUTED PHENYL)ALKYLAMINE N-MONOALKYL DERIVATIVES AND PROCESS FOR PRODUCING SAME<br/>[FR] DERIVES DE 1-( PHENYLE A SUBSTITUTION FLUORO,TRIFLUOROMETHYLE OU TRIFLUOROMETHOXY)ALKYLAMINE N-MONOALKYLE OPTIQUEMENT ACTIFS ET LEUR PROCEDE DE PRODUCTION
申请人:CENTRAL GLASS CO LTD
公开号:WO2004022521A1
公开(公告)日:2004-03-18
An optically active 1-(fluoro-, trifluoromethyl- or trifluoromethoxy-substituted phenyl)alkylamine N-monoalkyl derivative represented by the formula [4] is produced by a process including (a) reacting an optically active secondary amine, represented by the formula [1], with an alkylation agent R2-X, in the presence of a base, thereby converting the secondary amine into an optically active tertiary amine represented by the formula [3]; and (b) subjecting the tertiary amine to a hydrogenolysis, thereby producing the N-monoalkyl derivative,wherein R represents a fluorine atom, trifluoromethyl group or trifluoromethoxy group, n represents an integer of from 1 to 5, each of R1 and R2 independently represents an alkyl group having a carbon atom number of from 1 to 6, Me represents a methyl group, Ar represents a phenyl group or 1- or 2-naphthyl group, * represents a chiral carbon, and X represents a leaving group.
[reaction: see text] The highly regioselective hydrogenolysis of bis(alpha-methylbenzyl)amine derivatives proceeded with influence not from the electronic effect but from the steric effect of the trifluoromethyl substituent on the aromatic ring to provide a practical asymmetric synthesis of trifluoromethyl-substituted alpha-phenylethylamines.