Enantioselective 1,4‐Addition of Aliphatic <i>Grignard</i> Reagents to Enones Catalyzed by Readily Available Copper(I) thiolates derived from TADDOL. Preliminary communication

Abstract Two simple thiols derived from the parent TADDOL, α,α,α′,α′ tetraphenyl‐2,2‐dimethyl‐1,3‐clioxolan‐4,5‐dimethanol, are used to prepare Cu 1 complexes C and D to catalyze (0.05 equiv.) 1,4‐additions of Grignard reagents RMgCl to cyclic enones with enantioselectivities which are comparable to or better than previously reported (enantiomer ratios up to 92:8).