Chiral Brønsted acid catalyzed asymmetric oxidation of N‐acyl sulfenamide by H<sub>2</sub>O<sub>2</sub>: An efficient approach to obtaining chiral N‐acyl sulfinamide
Longjun Ma, Lizhe Bai, Zixuan Yu, Qinxu Shen
Abstract
Abstract Although the power of chiral sulfinamide reagents in synthetic chemistry has long been recognized, methods for their synthesis are still auxiliary‐based approaches which possess the disadvantages of poor atom economy and limited substrate universality. Due to the weak nucleophilicity of amides, it is more difficult to prepare chiral N‐acylsulfinamides by traditional methods. Herein, we describe an example of catalytic asymmetric synthesis of N‐acyl sulfinamides. In this work, N‐acyl sulfenamides act as useful substrates, because of the indispensable N−H bond, which could form an efficient hydrogen bond with chiral phosphoric acid. H 2 O 2 (35%) was used as the terminal oxidant for preparation of sulfinamides in high yields and enantioselectivities, which could be easily derivatized to sulfoxides without loss of the enantioselectivity.