One-Pot, Regioselective Synthesis of 1,3,5 Trisubstituted Hydantoins by Domino Condensation / aza-Michael / O→N acyl Migration of Asymmetric Carbodiimides with α,β-Unsaturated Carboxylic Acids

1,3,5 Trisubstituted hydantoins having two different substituents at the nitrogen atoms could be smoothly prepared by a domino condensation / aza-Michael / O→N acyl migration of asymmetric carbodiimides with activated α,β-unsaturated carboxylic acids. The regiochemical outcome of the process, as well as scope and limits, are discussed.