DBU-catalyzed Michael additions of bulky glycine imine to β-arylfuryl substituted α,β-unsaturated esters

AbstractDBU-catalyzed Michael reactions between tert-butyl 2-((diphenylmethylene) amino)acetate and simple β-substituted α,β-unsaturated esters have been achieved in high yields (up to 95% yield) and diastereoselectivties (up to 99:1 dr) in the presence of 1.0 eq. of LiBr in acetonitrile under room temperature. The Michael adduct can be easily converted into trans-3-substituted pyroglutamic acid ester through in-situ acidic hydrolysis following lactamation.Keywords: α,β-unsaturated esterDBUglycine imineMichael additionpyroglutamic acid Additional informationFundingThis work was supported by the National Natural Science Foundation of China (NSFC 21372259) and the Key R&D project in Shaanxi Province, China (2020ZDLSF03-09).