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Keywords:

  • aldehydes;
  • alkynes;
  • asymmetric catalysis;
  • metal catalysis;
  • organocatalysis

Abstract

The metallo-organocatalyzed enantioselective synthesis of various five-membered carbo- and heterocyclic structures through the merger of aminocatalysis with the catalytic indium(III) or copper(I) activation of α-disubstituted formyl alkynes is described. The use of indium trichloride associated with the (R)-1,1′-bis-(2-naphthylamine) ligand led to encouraging results with up to 85:15 enantiomeric ratio. After a careful examination of several other strategies, the best synergic catalytic system, which combines a chiral copper(I) complex with cyclohexylamine, afforded the enantioselective preparations of cyclopentane, indane, and pyrrolidine scaffolds with moderate to excellent control of the all-carbon quaternary stereogenic centers created through such cyclization processes.