Theoretical study on the reaction mechanisms of Michael chirality addition between propionaldehyde and nitroalkene catalyzed by an enantioselective catalyst

The asymmetric Michael addition between propionaldehyde and nitroalkene catalyzed by 8‐(ethoxycarbonyl)‐1,2,3,3a,8,8a‐hexahydropyrrolo[2,3‐b]indole‐2‐carboxylic acid has obtained relatively high yields and excellent enantioselectivities at room temperature. In this study, the molecular structures and optical activity of the most stable conformation I are optimized at B3LYP/6‐311++ G(d,p) level. We find that levorotatory conformation I catalyzing the same Michael addition can produce laevo‐product A and dextrorotatory conformation I′ can obtain the dextral‐product A'. These results have guiding significance for further studying on the new chemzymes and the mechanism of the obtained different chiral products.