申请人:Ishihara Sangyo Kaisha Ltd.
公开号:US05708175A1
公开(公告)日:1998-01-13
A process for producing 4-trifluoromethylnicotinic acid of the formula (VIII) or its salt: ##STR1## which comprises (i) a first step of reacting a halide of the formula (I): CF.sub.3 COHal (I) wherein Hal is a halogen atom, with a compound of the formula (II): CH.sub.2 .dbd.CHOR.sup.1 (II) wherein R.sup.1 is an alkyl group, in the presence of a base to obtain a 4-alkoxy-1,1,1-trifluoro-3-buten-2-one of the formula (III): CF.sub.3 CO--CH.dbd.CH--OR.sup.1 (III) wherein R.sup.1 is as defined above, and reacting this compound with ammonia to obtain 4-amino-1,1,1-trifluoro-3-buten-2-one of the formula (IV): ##STR2## and (ii) a second step of subjecting the 4-amino-1,1,1-trifluoro-3-buten-2-one obtained in the first step and a compound of the formula (V): ACO.sub.2 R.sup.2 (V) wherein R.sup.2 is an ester-forming residue, and A is (R.sup.3 O)CH.dbd.CH-- or (R.sup.3 O).sub.2 CHCH.sub.2 --, wherein R.sup.3 is an alkyl group, to a condensation reaction to obtain a compound of the formula (VI) (inclusive of its salt): ##STR3## wherein R.sup.2 is as defined above, and/or a compound of the formula (VII) (inclusive of its salt): ##STR4## wherein R.sup.2 and R.sup.3 are as defined above, as the reaction product, and then subjecting the reaction product to ring closure and hydrolysis.
生产4-三氟甲基烟酸(VIII)或其盐的方法:其中包括(i)第一步,将式(I)的卤化物:CF3COHal(I)其中Hal是卤素原子,与式(II)的化合物进行反应:CH2.dbd.CHOR1(II)其中R1是烷基基团,在碱的存在下获得式(III)的4-烷氧基-1,1,1-三氟-3-丁烯-2-酮:CF3CO--CH.dbd.CH--OR1(III)其中R1如上所定义,并将该化合物与氨反应以获得式(IV)的4-氨基-1,1,1-三氟-3-丁烯-2-酮:(IV):第二步,将第一步获得的4-氨基-1,1,1-三氟-3-丁烯-2-酮和式(V)的化合物进行反应:ACO2R2(V)其中R2是酯形成残基,A是(R3O)CH.dbd.CH--或(R3O)2CHCH2--其中R3是烷基基团,进行缩合反应以获得式(VI)的化合物(包括其盐):其中R2如上所定义,和/或式(VII)的化合物(包括其盐):其中R2和R3如上所定义,作为反应产物,然后将反应产物进行环闭合和水解。