会员体验
专利管家(专利管理)
工作空间(专利管理)
风险监控(情报监控)
数据分析(专利分析)
侵权分析(诉讼无效)
联系我们
交流群
官方交流:
QQ群: 891211   
微信请扫码    >>>
现在联系顾问~
热词
    • 17. 发明申请
    • PROCESS FOR THE SYNTHESIS OF CHIRALLY PURE β-AMINO-ALCOHOLS
    • WO2003050063A3
    • 2003-06-19
    • PCT/US2002/038119
    • 2002-11-26
    • WYETH
    • KREFT, Anthony, FrankANTANE, Madelene, MiyokoCOLE, Derek, CecilKUBRAK, Dennis, MartinRESNICK, LynnSTOCK, Joseph, RaymondWANG, Zheng
    • C07C51/15
    • A process is provided for preparing chirally pure S-enantiomers of α-amino acids comprising the steps of: a) preparing an organometallic reagent from an alkyl halide of the Formula (R) 2 CH(CH 2 ) n CH 2 X; b) adding the organometallic reagent to carbon dioxide to afford a carboxylic acid; c) activating the carboxylic acid with an acid chloride, phosphorus trichloride, acid anhydride, or thionyl chloride in the presence of a tertiary amine base; d) reacting the product of step c) with an alkali metal salt of S-4-benzyl-2-oxazolidinone; e) treating the product of step d) with a strong non-nucleophilic base to form an enolate anion; f) trapping the enolate anion with 2,4,6-triisopropylbenzenesulfonyl azide to afford an oxazolidinone azide; g) hydrolyzing the oxazolidinone azide with an aqueous base to afford an α-azido acid; h) reducing the α-azido acid to the α-amino acid; and i) recrystallizing the α-amino acid to the chirally pure α-amino acid. A process is also provided for preparing chirally pure S-enantiomers of β-amino alcohols further comprising the steps of reducing the crude α-amino acid to the β-amino alcohol and recrystallizing the β-amino alcohol to the chirally pure β-amino alcohol. A process is further provided for preparing chirally pure S enantiomers of N-sulfonyl β-amino alcohols further comprising the steps of sulfonylating the β-amino alcohol with 5-chloro-thiophene-2-sulfonyl halide; and recrystallizing to afford the chirally pure N-sulfonyl β-amino alcohols.