Jump to main content
Jump to site search

Issue 14, 2016
Previous Article Next Article

Supported bimetallic nano-alloys as highly active catalysts for the one-pot tandem synthesis of imines and secondary amines from nitrobenzene and alcohols

Author affiliations

Abstract

The synthesis and functionalization of imines and amines are key steps in the preparation of many fine chemicals and for pharmaceuticals in particular. Traditionally, metal complexes are used as homogeneous catalysts for these organic transformations. Here we report gold–palladium and ruthenium–palladium nano-alloys supported on TiO2 acting as highly efficient heterogeneous catalysts for the one-pot synthesis of the imine N-benzylideneaniline and the secondary amine N-benzylaniline directly from the easily available and stable nitrobenzene and benzyl alcohol precursors using a hydrogen auto-transfer strategy. These reactions were carried out without any added external hydrogen, sacrificial hydrogen donor or a homogeneous base. The bimetallic catalysts were prepared by the recently developed modified impregnation strategy, giving efficient control of size and nano-alloy composition. Both bimetallic catalysts were found to be far more active than their monometallic analogues due to a synergistic effect. Based on the turnover numbers the catalytic activities follow the order Ru < Pd < Au ≪ Au–Pd < Ru–Pd. Aberration corrected scanning transmission electron microscopy (AC-STEM) and X-ray absorption spectroscopy (XAFS) studies of these catalysts revealed that the reason for the observed synergistic effect is the electronic modification of the metal sites in the case of the Au–Pd system and a size stabilisation effect in the case of the Ru–Pd catalyst.

Graphical abstract: Supported bimetallic nano-alloys as highly active catalysts for the one-pot tandem synthesis of imines and secondary amines from nitrobenzene and alcohols

Back to tab navigation

Supplementary files

Publication details

The article was received on 25 Feb 2016, accepted on 22 Mar 2016 and first published on 23 Mar 2016


Article type: Paper
DOI: 10.1039/C6CY00425C
Author version
available:
Download author version (PDF)
Citation: Catal. Sci. Technol., 2016,6, 5473-5482
  • Open access: Creative Commons BY license
  •   Request permissions

    Supported bimetallic nano-alloys as highly active catalysts for the one-pot tandem synthesis of imines and secondary amines from nitrobenzene and alcohols

    M. Sankar, Q. He, S. Dawson, E. Nowicka, L. Lu, P. C. A. Bruijnincx, A. M. Beale, C. J. Kiely and B. M. Weckhuysen, Catal. Sci. Technol., 2016, 6, 5473
    DOI: 10.1039/C6CY00425C

    This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements