Organocatalytic Asymmetric Conjugate Addition of Aldehydes to Maleimides and Nitroalkenes in Deep Eutectic Solvents

A chiral primary amine-salicylamide is used as an organocatalyst for the enantioselective conjugate addition of α,α-disubstituted aldehydes to maleimides and nitroalkenes. The reactions are performed in deep eutectic solvents as reaction media at room temperature, leading to the corresponding adducts with enantioselectivities up to 88% (for maleimides) and 80% (for nitroalkenes). Catalyst and solvent can be recovered and reused.We thank the financial support from the Spanish Ministerio de Economía, Industria y Competitividad (CTQ201788171-P and PGC2018-096616-B-I00) and the University of Alicante (VIGROB-173, UADIF18-20 and UAUSTI18-05)