Highly Selective Reductive Cross-Amination between Aniline or Nitroarene Derivatives and Alkylamines Catalyzed by Polysilane-Immobilized Rh/Pt Bimetallic NanoparticlesThis work was partially supported by a Grant-in-Aid for Science Research from the Japan Society for the Promotion of Science (JSPS), the Global COE Program, The University of Tokyo, Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan, and the Japan Science and Technology Agency (JST). A. S. thanks the JSPS fellowship for Japanese Junior Scientist.
Accepted after revision: 17. Oktober 2018
18. Januar 2019 (online)
Published as part of the 30 Years SYNLETT – Pearl Anniversary Issue
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.
References and Notes
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