摘要：

Practical methods for the synthesis of (R)- or (S)-2,2′-bis(diarylphosphino)-1,1′-binaphthyls (BINAPs), useful ligands for transition-metal-catalyzed asymmetric reactions, have been developed. (±)-2,2′-Bis(diphenylphosphinyl)-1,1′-binaphthyl [(±)-BINAPO], prepared from 2,2′-dibromo-1,1′-binaphthyl and diphenylphosphinyl chloride, can be resolved into optical antipodes by the use of camphorsulfonic acid or 2,3-di-O-benzoyltartaric acid. Reduction of resolved BINAPO with trichlorosilane in the presence of triethylamine affords optically pure 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP). In a similar manner, several BINAP analogues have been prepared in optically pure form. The present procedures are suitable for obtaining these axially dissymmetric diphosphines in a large scale. The molecular structure of the 1:1:1 complex of (S)-( )-BINAPO, (1R)-(-)-camphorsulfonic acid, and acetic acid has been studied by single-crystal X-ray analysis.

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