Catalytic Asymmetric Mukaiyama–Mannich Reaction of Cyclic C-Acylimines with Difluoroenoxysilanes: Access to Difluoroalkylated Indolin-3-ones
摘要:
A catalytic enantioselective Mukaiyama-Mannich reaction of cyclic C-acylimines with difluoroenoxysilanes is reported.(S)-TRIP enables the enantioselective synthesis of a series of novel difluoroalkylated indolin-3-ones bearing a quaternary stereocenter in up to 97% yield and 98% ee. The synthetic utility of this protocol is highlighted by efficient conversion of the products to the corresponding indolin-3-one derivatives without any erosion of the enantiopurity.
Chiral phosphoric acid-catalyzed direct asymmetric mannich reaction of cyclic<i>C</i>-acylimines with simple ketones: facile access to C2-quaternary indolin-3-ones
作者:Jin-Shan Li、Yong-Jie Liu、Shen Li、Jun-An Ma
DOI:10.1039/c8cc05125a
日期:——
A chiral Brønsted acid-catalyzed directasymmetric Mannich reaction of simple ketones with cyclic C-acylimines has been established for the synthesis of C2-quaternary indolin-3-ones. In the presence of 5–10 mol% chiral phosphoric acid, a series of 2-(2-oxo-2-phenylethyl)-2-arylindolin-3-ones were obtained in good to high yield with up to 99% ee. The adducts obtained could be readily converted into
建立了手性布朗斯台德酸催化的简单酮类与环状C-酰基亚胺的直接不对称曼尼希反应,用于合成C2-季吲哚-3-酮。在5-10 mol%手性磷酸的存在下,以高达99%ee的良好或高收率获得了一系列2-(2-氧代-2-苯基乙基)-2-芳基吲哚-3-酮。通过简单的修饰,可以容易地将获得的加合物转化为二氢吲哚,三环吲哚-3-酮和四环四氢吲哚并[1,2- a ]喹啉。