1092379-97-9Relevant academic research and scientific papers
Thiourea-catalyzed asymmetric formal [3+2] cycloaddition of azomethine ylides with nitroolefins
Xie, Jianwu,Yoshida, Kohzo,Takasu, Kiyosei,Takemoto, Yoshiji
body text, p. 6910 - 6913 (2009/04/07)
A chiral thiourea catalyst possessing an amine function catalyzes an asymmetric [3+2] cycloaddition of azomethine ylides to nitroolefins to provide highly functionalized pyrrolidines with high diastereo- and enantioselectivities (up to 98:1:1 dr, 92% ee). The reaction proceeds in a stepwise manner consisting of Michael addition and subsequent intramolecular aza-Henry reaction. Both reactions are promoted by the thiourea catalyst, and the reaction rate of the latter step is efficiently enhanced by the addition of 2,2,2-trifluoroethanol.
