Issue 5, 2013

Binuclear chromium–salan complex catalyzed alternating copolymerization of epoxides and cyclic anhydrides

Abstract

Mono- and bi-nuclear chromium(III)–salan complexes are efficient catalysts for the alternating copolymerization of terminal epoxides [such as epichlorohydrin (ClPO) and glycidyl phenyl ether (GO)] and cyclic anhydrides [e.g. maleic anhydride (MA) and succinic anhydride (SA)] to afford the corresponding copolymers with >99% ester content. The binuclear complex c bearing a binaphthol linker showed significantly higher activity than the mononuclear chromium–salan complexes a and b. For example, the catalytic activities (based on chromium concentration) of complex c for MA/ClPO and MA/GO copolymerizations are 4.1 and 7.1 times that of complex a, respectively. An intramolecular bimetallic synergistic effect, in which the alternating chain-growth and dissociation of propagating copolymer species take turns at the two metal ions of the binuclear catalyst c, was suggested to make a contribution to the enhanced catalytic activity. Importantly, when using the binuclear complex c as a catalyst for MA/(S)-GO copolymerization, a highly regioregular ring-opening step was observed with a concomitant >99% retention of configuration at the methine carbon center of epoxide incorporated into the polyester.

Graphical abstract: Binuclear chromium–salan complex catalyzed alternating copolymerization of epoxides and cyclic anhydrides

Supplementary files

Article information

Article type
Paper
Submitted
10 Oct 2012
Accepted
29 Nov 2012
First published
30 Nov 2012

Polym. Chem., 2013,4, 1439-1444

Binuclear chromium–salan complex catalyzed alternating copolymerization of epoxides and cyclic anhydrides

J. Liu, Y. Bao, Y. Liu, W. Ren and X. Lu, Polym. Chem., 2013, 4, 1439 DOI: 10.1039/C2PY20842C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements