申请人:Ethyl Corporation
公开号:US04590010A1
公开(公告)日:1986-05-20
6-Alkoxy-5-trifluoromethyl-1-naphthoic acids are prepared by (1) cyanating a 6-alkoxytetralone so as to form a 6-alkoxy-1-cyano-3,4-dihydronaphthalene, (2) converting the 6-alkoxy-1-cyano-3,4-dihydronaphthalene to a naphthoic acid precursor selected from a 6-alkoxy-1-cyanonaphthalene and a hydrocarbyl 6-alkoxy-1-naphthoate, (3) halogenating the naphthoic acid precursor to the corresponding 5-halo derivative, (4) trifluoromethylating the 5-halo derivative to replace the 5-halo substituent with a 5-trifluoromethyl group, and (5) hydrolyzing the resultant product to a 6-alkoxy-5-trifluoromethyl-1-naphthoic acid. In a preferred embodiment of the invention, the process is conducted so as to prepare 6-methoxy-5-trifluoromethyl-1-naphthoic acid, which, like the other products, is known to be useful as a pharmaceutical intermediate.
6-烷氧基-5-三氟甲基-1-萘甲酸的制备方法为:(1)氰化6-烷氧基四酮以形成6-烷氧基-1-氰基-3,4-二氢萘烯,(2)将6-烷氧基-1-氰基-3,4-二氢萘烯转化为选自6-烷氧基-1-氰基萘烯和烃基6-烷氧基-1-萘酸酯的萘甲酸前体,(3)卤代化萘甲酸前体以得到相应的5-卤代衍生物,(4)三氟甲基化5-卤代衍生物以用三氟甲基基团取代5-卤代取代基,(5)水解所得产物以得到6-烷氧基-5-三氟甲基-1-萘甲酸。在本发明的一种优选实施例中,该过程被进行以制备6-甲氧基-5-三氟甲基-1-萘甲酸,像其他产物一样,已知对其作为制药中间体是有用的。