A new and effective method for providing optically active monosubstituted malononitriles: selective reduction of α,β-unsaturated dinitriles catalyzed by copper hydride complexes

A copper hydride complex, which was generated in situ from CuOt-Bu, BINAP, and PhSiH3, was found to be a highly effective catalyst for the reduction of the CC of α,β-unsaturated dinitriles. In addition to CuOt-Bu, some air and moisture stable Cu salts were also effective as catalyst precursors in this reduction. Herein, we have developed an effective method for providing optically active monosubstituted malononitriles.

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(R)-1,1-Dicyano-2-phenylpropaneC11H10N2Ee = 80%[α]D20=+13.3 (c 0.59, EtOH)Source of chirality: asymmetric catalysisAbsolute configuration: (R)

(S)-(−)-2,2′-Bis(diphenylphosphino)-1,1′-binaphthylC44H32P2Ee >99%[α]D20=-234.0 (c 0.30, toluene)Source of chirality: asymmetric synthesisAbsolute configuration: (S)