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Updated: Aug 4, 2025

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Synthesis and ring-opening metathesis polymerisation of o-alkoxy benzothiadiazole paracyclophane-1,9-dienes
Yurachat Janpatompong1, Venukrishnan Komanduri1, Raja U Khan1
1Organic Materials Innovation Centre (OMIC), Department of Chemistry, The University of Manchester, Oxford Road, Manchester, M13 9PL, UK. michael.turner@manchester.ac.uk.
Abstract:
ortho-Diethylhexyloxyphenylene benzothiadiazole paracyclophane-1,9-diene as a mixture of diastereomers was synthesized by a sequential benzyne-induced Stevens rearrangement, oxidation and pyrolysis of a dithia[3.3]paracyclophane. Reaction of these highly strained cyclophanedienes with the second generation Grubbs catalyst showed that they can be ring opened to alternating cis,trans-phenylenevinylene polymers. In situ NMR experiments showed that one isomer 8a polymerised to 90% conversion, whereas the other 8b gave only 9% conversion due to steric hindrance on both faces of the alkene bridges of this isomer. The resulting polymers can be readily isomerized in dilute solution using visible light to the all-trans isomer and the optical and electrochemical properties of these polymers were examined by theory and experiment.
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