An asymmetric relay catalysis strategy merging gold and oxidative N-heterocyclic carbenes (NHCs) for trimolecular reactions was disclosed. Racemic α-amino-ynones undergo facile conversion to racemic pyrrolin-3-ones under gold catalysis, which serve as potent nucleophilic C1 synthons, which engage easily available enals and phenols to generate linear products in moderate yields and excellent diastereo- and enantioselectivities under oxidative NHC catalysis. Synthetic utility of 2,2-disubstituted pyrrolinones is also demonstrated by facile conversion to pyrrolinone-fused γ-lactames in high yields.
Wang et al. (Sun,) studied this question.