Enantioselective Reformatsky Reaction of Ketones Catalyzed by Chiral Indolinylmethanol

A reliable and practical Reformatsky reaction of ethyl iodide acetate with ketones for the synthesis of chiral β‐hydroxyl carbonyl compounds in good yields and excellent enantioselectivities is presented. A readily available dihydroindole derivative was used as chiral catalyst, ethyl iodide acetate was the nucleophile, and Me2Zn was the zinc source. The presence of air was found to be essential for the efficient construction of new carbon–carbon bonds through a radical pathway. Asymmetric Reformatsky reaction of ethyl iodide acetate with ketones was realized via the initiation of Me2Zn and the proper stereocontrol of the chiral Zn‐indolinylmethanol complex. Various chiral β‐hydroxyl carbonyl compounds were obtained in good yields and excellent enantioselectivities (up to 97 % ee).