Halogenative kinetic resolution of β-amido alcohols: chiral BINAP-mediated SN2 displacement of hydroxy groups by chlorides with inversion of stereochemistry

A series of optically active cyclic trans-β-amido alcohols were obtained by the non-enzymatic kinetic resolution of the corresponding racemic amido alcohols using commercially available (S)-BINAP and NCS by SN2 halogenation of the hydroxy group. The product, cis-β-amido chloride, was also obtained in optically active form with an inversion of stereochemistry.

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N-((1R,2R)-2-Hydroxycyclohexyl)-4-methylbenzenesulfonamideC13H19NO3SEe = 79%[α]D25=-1.7 (c 1.0, CHCl3)Source of chirality: halogenative kinetic resolutionAbsolute configuration: (1R,2R)

N-((1R,2S)-2-Chlorocyclohexyl)-4-methylbenzenesulfonamideC13H18ClNO2SEe = 56%[α]D25=-20.2 (c 1.0, CHCl3)Source of chirality: halogenative kinetic resolutionAbsolute Configuration: (1R,2S)