申请人:ISP INVESTMENTS INC.
公开号:US20040180928A1
公开(公告)日:2004-09-16
The present invention provides a new and efficient process for the preparation of the dexmethylphenidate hydrochloride with high optical purity, the process comprising:
(a) reacting a solution of threo-N-Boc-ritalinic acid with (S)-1-phenylethylamine, separating precipitated solid salt of (R,R)-enriched N-Boc-ritalinic acid with (S)-1-phenylethylamnine from the reaction mixture and recrystallizing, reslurring and/or trituring of said salt;
(b) mixing the solid salt of (R,R)-N-Boc-ritalinic acid and (S)-1-phenylethylamine obtained in step (a) with aqueous acid and separating (R,R)-N-Boc-ritalinic acid from the mixture; and
(c) reacting the (R,R)-N-Boc-ritalinic acid prepared in step (b) with hydrogen chloride and methanol to give dexmethylphenidate hydrochloride with optical purity of at least 99% ee.
The present invention further provides salt of (R,R)-N-Boc-ritalinic acid with (S)-1-phenylethylamine as new intermediate in the preparation of dexmethylphenidate hydrochloride.
本发明提供了一种新的高光学纯度地地辛美非特酯盐的制备方法,该方法包括:(a)将threo-N-Boc-利他林酸的溶液与(S)-1-苯乙胺反应,从反应混合物中分离出(R,R)-富集的N-Boc-利他林酸的沉淀固体盐和(S)-1-苯乙胺,再结晶、重悬浸和/或研磨该盐;(b)将步骤(a)中得到的(R,R)-N-Boc-利他林酸固体盐与(S)-1-苯乙胺混合后,加入水酸进行混合,然后从混合物中分离出(R,R)-N-Boc-利他林酸;(c)将步骤(b)中制备的(R,R)-N-Boc-利他林酸与氯化氢和甲醇反应,得到光学纯度至少为99% ee的地地辛美非特酯盐。本发明还提供了(R,R)-N-Boc-利他林酸与(S)-1-苯乙胺的盐作为地地辛美非特酯盐制备的新中间体。