A New Enantioselective Synthetic Approach to β-Aminothio-Compoundsvia enantioselective reduction ofN,S-heterocyclic imines
摘要:
The enantioselective reduction of N,S-heterocyclic imines, namely thiazolines la,b and 2H-1,4-benzothiazine Ic, via three different reduction methods is reported. The influence of reaction parameters, substituents, and the type of heterocycle was investigated. Reduction of the prochiral imines led to the corresponding amine derivatives 2, 10, 12 and 14. The best result was obtained by stoichiometric enantioselective reduction of Ic with 44% ee.
Umpolung Strategy with 2‐Aminothiophenols: Access to 2‐Arylbenzothiazine Derivatives from Alkyl Aryl Ketones
作者:Thanh Binh Nguyen、Pascal Retailleau
DOI:10.1002/adsc.202000964
日期:2020.12.8
Strong Brønsted acids were found to catalyze the oxidative condensation of 2‐aminothiophenols with aryl alkyl ketones in DMSO to provide a wide range of complex 2‐arylbenzothiazines. With acetophenones, dimeric 2‐arylbenzothiazines were formed. On the other hand, the reaction with propiophenones resulted in 2:1 adducts whereas 1:1 adducts were produced with isobutyrophenones, benzoylacetonitrile and