Premium
Highly Enantioselective Synthesis of 3‐Amino‐2‐oxindole Derivatives: Catalytic Asymmetric α‐Amination of 3‐Substituted 2‐Oxindoles with a Chiral Scandium Complex
Author(s) -
Yang Zhigang,
Wang Zhen,
Bai Sha,
Shen Ke,
Chen Donghui,
Liu Xiaohua,
Lin Lili,
Feng Xiaoming
Publication year - 2010
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.201000126
Subject(s) - enantioselective synthesis , oxindole , stereocenter , amination , trifluoromethanesulfonate , scandium , chemistry , catalysis , combinatorial chemistry , organic chemistry
A highly enantioselective α‐amination of 3‐substituted oxindoles with azodicarboxylates catalyzed by a chiral Sc(OTf) 3 / N , N ′‐dioxide complex (Tf: triflate) has been developed and affords the corresponding 3‐amino‐2‐oxindole derivatives in high yields (up to 98 %) with excellent enantioselectivities (up to 99 % ee ). The procedure is capable of tolerating a relatively wide range of substrates, and excellent results (92–96 % ee ) can also be obtained, even in the presence of 0.5 mol % of catalyst loading under mild conditions. These results showed the potential value of the catalytic approach. Moreover, with high synthetic versatility, the product could be easily transformed into optically active 3‐amino‐3‐methyloxindole bearing a chiral quaternary stereogenic center.