Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance work on Wednesday 27th March 2019 from 11:00 AM to 1:00 PM (GMT).

During this time our website performance may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.

Issue 6, 2019
Previous Article Next Article

Heterogeneous viologen catalysts for metal-free and selective oxidations

Author affiliations


Metal-free oxidation, a green chemistry process, has drawn significant attention from catalysis researchers. However, most oxidation processes are completed by homogeneous metal-free catalysts, whereas heterogeneous metal-free materials have been developed with limited successes. In this study, polymerized ionic networks (PINs) with N,N′-dialkyl-4,4′-bipyridinium units as heterogeneous viologen type of catalysts exhibited high efficiency in the oxidation of aromatic sulfides/alcohols to sulfoxides/aldehydes, respectively (conversion: >90%, selectivity: >95%). The catalytic performance of PINs originates from the electron-accepting ability of the viologen unit, which can reduce H2O2 into an active species. Especially, the synthesis of PIN catalysts is a one-step simple polymerization reaction between benzyl bromide and bipyridine in air. The metal-free heterogeneous feature, high selectivity, mild conditions (60 °C, 1 h), and the facile preparation of the catalyst make the current selective oxidation approach attractive.

Graphical abstract: Heterogeneous viologen catalysts for metal-free and selective oxidations

Back to tab navigation

Supplementary files

Publication details

The article was received on 03 Dec 2018, accepted on 04 Feb 2019 and first published on 04 Feb 2019

Article type: Paper
DOI: 10.1039/C8GC03772H
Citation: Green Chem., 2019,21, 1455-1460

  •   Request permissions

    Heterogeneous viologen catalysts for metal-free and selective oxidations

    S. Hou, N. Chen, P. Zhang and S. Dai, Green Chem., 2019, 21, 1455
    DOI: 10.1039/C8GC03772H

Search articles by author