[EN] NOVEL PROCESS FOR THE PREPARATION OF 4-ARYL-3-HYDROXYMETHYL-1-METHYLPIPERIDINES.<br/>[FR] NOUVEAU PROCEDE DE PREPARATION DE 4-ARYL-3-HYDROXYMETHYL-1-METHYLPIPERIDINES
申请人:NATCO PHARMA LTD
公开号:WO2004043921A1
公开(公告)日:2004-05-27
A novel, improved, and general process for the preparation of 4-aryl-3-hydroxymethyl-1-methylpiperidines is disclosed in the present invention. 4-(4-Fluorophenyl)-3-hydroxymethyl-1-methylpiperidine is a well-known intermediate in making the anti-depressant drug, paroxetine ((-)-trans-4-p-fluorophenyl-3-(3',4'-methylenedioxy-phenoxymethyl)piperidine). Novel N-methyl-N-[3-(4-substitutedphenyl (F, Me, OMe))-3-hydroxy]propylamines are prepared from the Mannich salts such as 3-dimethylamino- or 3-(N-methyl-N-benzylamino)-4'-substituted (F, Me, OMe) propiophenone hydrochlorides by conventional methods. The N-methyl-N-[3-(4-substitutedphenyl (H, F, Me, OMe))-3-hydroxy]propylamines thus obtained are reacted with ethyl or methyl acrylate to get the corresponding Michael addition products. The hydroxy group present in the Michael addition products is converted into a facile leaving group and treated with a strong base to get 4-aryl-N-methylpiperidine-3-carboxylates via the intramolecular cyclization in good yields. Reduction of the ester group present in these piperidine-3-carboxylates gave the title compounds as crystalline solids. Present process is easily adaptable for commercial preparation of the paroxetine intermediate (4-(4-fluorophenyl)-3-hydroxymethyl-1-methylpiperidine).
本发明揭示了一种新颖的、改进的、通用的制备4-芳基-3-羟甲基-1-甲基哌啶的方法。4-(4-氟苯基)-3-羟甲基-1-甲基哌啶是制造抗抑郁药物帕罗西汀((-)-trans-4-p-氟苯基-3-(3',4'-亚甲二氧基苯氧甲基)哌啶)的已知中间体。新型的N-甲基-N-[3-(4-取代苯基(F,Me,OMe))-3-羟基]丙胺可通过常规方法从Mannich盐制备而来,例如3-二甲氨基或3-(N-甲基-N-苄基氨基)-4'-取代(F,Me,OMe)丙酮盐酸盐。因此获得的N-甲基-N-[3-(4-取代苯基(H,F,Me,OMe))-3-羟基]丙胺与乙基或甲基丙烯酸酯反应,得到相应的Michael加成产物。Michael加成产物中存在的羟基转化为容易离去的基团,并用强碱处理,通过分子内环化以良好的产率得到4-芳基-N-甲基哌啶-3-羧酸酯。这些哌啶-3-羧酸酯中存在的酯基还原后,得到了晶体固体的目标化合物。目前的方法易于用于商业制备帕罗西汀中间体(4-(4-氟苯基)-3-羟甲基-1-甲基哌啶)。