申请人:Kumar Ashok
公开号:US20080097101A1
公开(公告)日:2008-04-24
An improved process for the manufacture of Clopidogrel starting from 2-(2-thienyl) ethylamine, which eliminates the isolation of an unstable intermediate like 2-(2-thienyl) ethyl formimine by subjecting it to a one pot cyclization to get 4, 5, 6, 7-tetrahydrothieno (3,2-c) pyridine of Formula II and further reacting with halo-compound of Formula III (where X is Cl or Br) at 20 to 90° C. temperature characterized in a solvent like water and/or dichloroethane in presence of organic or inorganic bases is disclosed herein. This invention further discloses a process for resolution of racemic Clopidogrel into its optical antipodes and converting the dextroclopidogrel base into its known polymorphs namely ‘Form I’ or ‘Form II’ in solvents selected from methyl propyl ketone, methyl isopropyl ketone, diethyl ketone or their mixture thereof, mixture of ethyl acetate and methyl propyl ketone, mixture of ethyl acetate and methyl isopropyl ketone, or mixture of ethyl acetate and diethyl ketone or ethyl acetate.
一种改进的克洛匹多制造工艺,从2-(2-噻吩基)乙胺开始,通过一锅法环化得到式II的4,5,6,7-四氢噻吩[3,2-c]吡啶,进一步在20到90℃的温度下,在水和/或二氯乙烷等溶剂中,在有机或无机碱的存在下与式III的卤素化合物(其中X是Cl或Br)反应,从而消除了2-(2-噻吩基)乙醛缩合物这种不稳定中间体的分离。本发明还揭示了一种将混合体克洛匹多分离成其光学对映体,并将右旋克洛匹多碱转化为其已知的多晶型‘Form I’或‘Form II’的工艺,所述溶剂选自丙酮、异丙酮、乙酰丙酮或其混合物、乙酸乙酯和丙酮的混合物、乙酸乙酯和异丙酮的混合物,或乙酸乙酯和乙酮的混合物。