Synthesis of Enantiomerically Enriched Imidazolidin‐2‐Ones through Asymmetric Palladium‐Catalyzed Alkene Carboamination Reactions

Abstract

Positive water effect: A catalyst composed of [Pd(2)(dba)(3)] (dba=dibenzylideneacetone) and (S)-Siphos-PE is effective for the enantioselective coupling of N-allyl ureas with aryl bromides to afford 4-substituted imidazolidin-2-ones. Added water leads to significantly improved enantioselectivities with electron-poor aryl halide substrates. It is suggested that the C-C bond-forming reductive elimination is the enantiodetermining step in these reactions.