Organocatalytic Asymmetric Michael Addition of 3-Pyrrolyloxindoles to β-Phthalimidonitroethene for the Synthesis of 3,3'-Disubstituted Oxindoles Bearing Contiguous 3,α,β-Triamino Functionality.
An organocatalytic asymmetric Michael addition reaction of 3-pyrrolyloxindoles to β-phthalimidonitroethene has been developed with a bifunctional thiourea-tertiary amine as the catalyst. A range of 3,3'-disubstituted oxindoles bearing contiguous 3,α,β-triamino functionality could be obtained in high yields with good diastereoselectivities and high enantioselectivities (up to 99% yield, 99:1 dr, and 98% ee). The higher reactivity of β-phthalimidonitroethene compared to the reactivity of ordinary nitroalkenes in the reaction with 3-pyrrolyloxindoles was demonstrated by contrast experiments.
University of Chinese Academy of Sciences , Beijing 100049, China.
Yong
Y
You
Zhi-Jun
ZJ
Wu
University of Chinese Academy of Sciences , Beijing 100049, China.
Jian-Feng
JF
Chen
University of Chinese Academy of Sciences , Beijing 100049, China.
Zhen-Hua
ZH
Wang
Xiao-Ying
XY
Xu
Xiao-Mei
XM
Zhang
Wei-Cheng
WC
Yuan