Organocatalytic Asymmetric Aza-Henry Reaction

Significance

An organocatalytic asymmetric aza-Henry reaction has been described. Imines, generated in situ from α-amido sulfones 1, react with nitromethane and cesium hydroxide in the presence of 12 mol% of a chiral quininium salt 2 to give protected nitroamines 3. Linear and branched alkyl substrates, as well as aryl precursors provide the products in good yields and enantioselectivities. Furthermore, nitroethane can also be used yielding the corresponding products 4 in high syn/anti ratios and similarly good enan­tioselectivities.