Conformational enantiodiscrimination for asymmetric construction of atropisomers

Nat Commun. 2022 Aug 12;13(1):4735. doi: 10.1038/s41467-022-32432-8.

Abstract

Molecular conformations induced by the rotation about single bonds play a crucial role in chemical transformations. Revealing the relationship between the conformations of chiral catalysts and the enantiodiscrimination is a formidable challenge due to the great difficulty in isolating the conformers. Herein, we report a chiral catalytic system composed of an achiral catalytically active unit and an axially chiral 1,1'-bi-2-naphthol (BINOL) unit which are connected via a C-O single bond. The two conformers of the catalyst induced by the rotation about the C-O bond, are determined via single-crystal X-ray diffraction and found to respectively lead to the formation of highly important axially chiral 1,1'-binaphthyl-2,2'-diamine (BINAM) and 2-amino-2'-hydroxy-1,1'-binaphthyl (NOBIN) derivatives in high yields (up to 98%), with excellent enantioselectivities (up to 98:2 e.r.) and opposite absolute configurations. The results highlight the importance of conformational dynamics of chiral catalysts in asymmetric catalysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Crystallography, X-Ray
  • Diamines* / chemistry
  • Molecular Conformation

Substances

  • Diamines