A Simple and General Nickel-Catalyzed Michael-Type Hydroamination of Activated Olefins Using Arylamines

A simple and general addition of aromatic amines to activated olefins viz; acrylonitrile, phenyl vinyl sulfone and dimethyl maleate were realized using a combination of 1–10 mol% of NiBr2 and 2–20 mol% of AgOTf at 27–100 °C in toluene as solvent. A variety of aromatic amines bearing both electron donating and electron withdrawing groups including sterically demanding ones, as well as heteroaromatic amines could be added to activated olefins giving rise to the desired β-amino acid derivatives or β-amino sulfones in good yields. Addition of anilines to acrylonitrile was also found to be progressing when AgOTf alone was used as catalyst but was far less effective when compared to catalysis in the presence of NiBr2.