Asymmetric Stepwise Reductive Amination of Sulfonamides, Sulfamates and a Phosphinamide via Nickel Catalysis.

asymmetric reductive amination of poorly nucleophilic sulfonamides is realized in the presence of nickel catalysts and titanium alkoxide. A wide range of enolizable ketones, including some dialkyl and biaryl ketones, were converted in one pot to sulfonamides in excellent enantiomeric excess. The method is also applicable to cyclization of sulfamates and intermolecular reductive amination of a diarylphosphinamide. Formic acid was used as a safe and economic surrogate of high-pressure hydrogen gas.