Highly Selective Reductive Cross-Amination between Aniline or Nitroarene Derivatives and Alkylamines Catalyzed by Polysilane-Immobilized Rh/Pt Bimetallic Nanoparticles

Reductive cross-amination between imine intermediates generated through partial hydrogenation of aniline or nitroarene derivatives and alkylamines is an ideal method for obtaining N-alkylated cyclohexylamine derivatives; however, no such transformations have hitherto been established. Here, we report a highly selective reductive cross-amination using aniline derivatives and alkylamines catalyzed by heterogeneous Rh/Pt bimetallic nanoparticles under mild conditions. The catalyst was recovered and reused for five runs, keeping high activity. In this reaction, imine intermediates generated during the course of partial hydrogenation of aniline derivatives were trapped immediately by strongly interacting primary alkylamines with the catalyst, which caused a highly selective transformation to give the desired products, while suppressing dicyclohexylamine formation.