[摘要]:Reaction of carbodiimides with a-bromo(chloro)arylacetates produces N,N'-substituted 5-arylhydantoins under very mild conditions and with high yields. When the carbodiimides are generated in situ by Staudinger reaction, the process becomes a 1-pot, 3-component sequential synthesis of libraries of differently substituted 5-arylhydantoins.