Synlett 2016; 27(05): 759-762
DOI: 10.1055/s-0035-1561330
cluster
© Georg Thieme Verlag Stuttgart · New York

Comparison of Pyrylium and Thiopyrylium Photooxidants in Metal-Free Ring-Opening Metathesis Polymerization

Laura M. M. Pascual
,
Damian G. Dunford
,
Adam E. Goetz
,
Kelli A. Ogawa
,
Andrew J. Boydston*
Further Information

Publication History

Received: 23 October 2015

Accepted after revision: 28 December 2015

Publication Date:
27 January 2016 (online)

Abstract

Systematically varied pyrylium and thiopyrylium photo-oxidants have been evaluated in the metal-free ring-opening-metathesis polymerization (MF-ROMP) of norbornene. Across the series, we observed higher conversion into polynorbornene from thiopyrylium species in comparison with pyrylium salts that were otherwise similarly functionalized. Additionally, more electron-rich photo-oxidants (i.e., weaker oxidants) correlated with higher conversions.

Supporting Information

 
  • References and Notes

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