Increasing molecular weight parameters of a helical polymer through polymerization in a chiral solvent

Simon J Holder; Mariliz Achilleos; Richard G Jones

doi:10.1021/ja064587e

Increasing molecular weight parameters of a helical polymer through polymerization in a chiral solvent

J Am Chem Soc. 2006 Sep 27;128(38):12418-9. doi: 10.1021/ja064587e.

Authors

Simon J Holder¹, Mariliz Achilleos, Richard G Jones

Affiliation

¹ Functional Materials Group, School of Physical Sciences, University of Kent, Canterbury, Kent CT2 7NH, UK. S.J.Holder@kent.ac.uk

PMID: 16984183
DOI: 10.1021/ja064587e

Abstract

In this communication, we will demonstrate that polymerization in a chiral solvent can affect the molecular weight distribution of the product by perturbing the balance of the P and M helical screw senses of the growing chains. Specifically, for the Wurtz-type synthesis of polymethylphenylsilane (PMPS) in either (R) or (S)-limonene, the weight-average molecular weight of the products (average Mw = 80 000) was twice that of PMPS synthesized in (R/S)-limonene (average Mw = 39 200). Peturbation of the helical segmentation along the polymer chains leads to a reduction in the rate of occurrence of a key termination step. This the first time that a chiral solvent has been demonstrated to have such an effect on a polymerization process in affecting molecular weight parameters in contrast to affecting tacticity.