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Updated: Aug 15, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Termination and side-reactions of polystyryllithium with beta-bromostyrene
Norman J Ward1, Howell G M Edwards
1Chemical and Forensic Sciences, Interdisciplinary Research Centre for Polymer Science and Technology, University of Bradford, Bradford, West Yorkshire BD7 IDP, UK.
Abstract:
Low molecular weight polystyryllithium was synthesised and terminated with a two-fold molar excess of beta-bromostyrene to produce an end-functionalised polymer. 1,3-Diphenylallyl-terminated polystyrene and other reaction products were analysed by FT-Raman spectroscopy. By comparison with model compounds, it can be deduced that beta-bromostyrene with a predominantly trans configuration gave rise to primarily cis conformational unsaturation at the polystyrene chain-end. It was also demonstrated that a polystyrene 'dimer' and 1,4-diphenylbutadiene were produced via side-reactions which are considered to result from metal-halogen exchange in the reagents.
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