Catalyst- and Base-Free Synthesis of Morita-Baylis-Hillman and Rauhut-Currier Adducts of β-Aminonitroalkenes.

A facile, base- and catalyst-free synthesis of Morita-Baylis-Hillman and Rauhut-Currier adducts of β-aminonitroalkenes with different electrophiles such as ethyl glyoxylate, trifluoropyruvate, ninhydrin, vinyl sulfone, and N -tosylazadiene is reported. The products are formed in good to excellent yields at room temperature with a broad substrate scope. The adducts of ninhydrin and β-aminonitroalkene spontaneously cyclize to fused indenopyrroles. Gram-scale reactions and synthetic transformations of the adducts are also reported here.