Process for producing 4-trifluoromethylnicotinic acid
    3.
    发明授权
    Process for producing 4-trifluoromethylnicotinic acid 失效
    生产4-三氟甲基烟酸的方法

    公开(公告)号:US5708175A

    公开(公告)日:1998-01-13

    申请号:US648761

    申请日:1996-05-16

    摘要: 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.

    摘要翻译: (VIII)的4-三氟甲基烟酸或其盐:(Ⅷ)的方法,其包括(ⅰ)使式(I)的卤化物:CF 3 COHal(I)(其中Hal为 卤素原子与式(II)的化合物:CH 2 = CHOR 1(II)其中R 1是烷基,在碱的存在下,得到4-烷氧基-1,1,1-三氟-3- (III)的丁烯-2-酮:CF 3 CO-CH = CH-OR 1(III)其中R 1如上定义,并使该化合物与氨反应,得到4-氨基-1,1,1-三氟-3 (IV)的2-丁烯-2-酮:(IV)和(ii)第二步,将得到的4-氨基-1,1,1-三氟-3-丁烯-2-酮 第一步和式(V)化合物:其中R 2为酯形成残基,A为(R 3 O)CH = CH-或(R 3 O)2 CHCH 2 - ,其中R 3为烷基, 进行缩合反应,得到式(VI)化合物(包括其盐):其中R 2如上所定义,和/或式 (VII)(包括其盐):其中R2和R3如上定义,作为反应产物,然后使反应产物闭环并水解。