The present invention provides an improved process for preparation of the substantially pure (3a R,7a R)-4'-(benzo[d]isothiazol-3-yl)octahydrospiro[isoindole-2,1'-piperazin]-1'-ium methanesulfonate (referred to as compound-II), which is useful as a key intermediate for the synthesis of lurasidone ((3a R,4S,7R,7a S)-2-(1R,2R)-2-[4-(1,2-benzisothiazol-3- yl)piperazin-1ylmethyl] cyclohexylmethyl}hexahydro-4,7-methano-2H-isoindole-1,3-dione). The process comprises reaction of the compound-III (as described herein) with the compound-IV (as described herein) in the presence of a solvent mixture selected from an alcohol and water; and a base The improved process for the preparation of compound II provides the product with total amount of unreacted compound-IV as impurity in less than 0.06 % and the product with HPLC purity as ≥ 99.8%. The process further refers purification of Lurasidone hydrochloride, wherein the product contains the residual acetone < 5000 ppm.
本发明提供了一种改进的制备过程,用于制备几乎纯的(3aR,7aR)-4'-(苯并[d]
异噻唑-3-基)八氢螺[异
吲哚-2,1'-
哌嗪]-1'-
甲磺酸盐(称为化合物II),该化合物是合成
卢拉西酮的关键中间体((3aR,4S,7R,7aS)-2-(1R,2R)-2-[4-(1,2-苯并
异噻唑-3-基)
哌嗪-1-基甲基]环己基甲基}六氢-4,7-甲基-
2H-异吲哚-1,3-二酮)。该过程包括将化合物III(如本文所述)与化合物IV(如本文所述)在醇和
水的溶剂混合物和碱的存在下反应;改进的制备化合物II的过程可在不到0.06%的未反应化合物IV总量的情况下提供产品,并且产品的HPLC纯度为≥99.8%。该过程还涉及
卢拉西酮盐酸盐的纯化,其中产品中残留的
丙酮<5000 ppm。