Symmetry breaking in asymmetric catalysis: Racemic catalysis to autocatalysis

Recently, novel approaches for symmetry breaking in asymmetric catalysis were reported. Thus, the racemic catalysts can be enantiomer-selectively transformed into a highly activated enantiomeric catalyst by additional chiral sources. The nonequivalence of enantiomeric catalysts resulting from the spontaneous breaking of racemic catalysts was amplified by an asymmetric autocatalytic process. This paper discusses the recent progress in chirally economical racemic catalysis and followed by asymmetric amplification and autocatalysis.