Efficient base-free asymmetric one-pot synthesis of spiro[indoline-3,3′-pyrrolizin]-2-one derivatives catalyzed by chiral organocatalyst

A 1,3-dipolar cycloaddition reaction has been performed under organocatalytic conditions with high enantioselectivity by the utilization of bipyridine-based chiral quaternary ammonium bromide as an organocatalyst. Here, the reaction of 1,3-dipolar cycloaddition of azomethine ylide generated in situ from the decarboxylative condensation of α -amino acids and non-enolizable 1,2-diketones to the above dipolarophiles takes place.