Cooperative asymmetric catalysis using thioamides toward truly practical organic syntheses

Asymmetric catalysis has established its unwavering position in organic chemistry as a particularly efficient strategy for the production of enantiomerically enriched compounds. For a truly practical synthetic protocol, however, asymmetric catalysis must be endowed with high atom economy and sustainability. Cooperative activation is a powerful strategy to drive efficient asymmetric catalysis without the use of stoichiometric activating reagents, leading to asymmetric catalysis with minimum waste production. This review summarizes the utility of thioamides as an emerging functional group class in cooperative asymmetric catalysis. Soft Lewis acid/hard Brønsted base cooperative catalysts, in which thioamides serve as either electrophiles or pronucleophiles, promote asymmetric C-C bond-forming reactions with perfect atom economy.