Borrowing hydrogen in an indirect asymmetric Wittig reaction

An asymmetric C–C bond formation has been achieved by iridium-catalysed coupling of benzyl alcohol with a phosphonium ylide using a borrowing hydrogen strategy.

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(R)-Ethyl 2-methyl-3-phenylpropionateC12H16O2Ee = 87%[α]D21=-13.7 (c 2.85, EtOH)Source of chirality: asymmetric synthesisAbsolute configuration: (R)