It is demonstrated here that three different α-amino N-carboxyanhydrides (NCAs), including for the first time O-benzyl-L-threonine NCA, can be polymerized in a controlled/living" fashion without the need for transition metal catalysts or complex custom-made glassware. Homopolymerizations in tetrahydrofuran gave monomodal distributions, high conversions, predictable Mn values and displayed first-order kinetics. Chain extension experiments from poly(benzyl-L-threonine), using N,N-dimethylacetamide to avoid the formation of insoluble β-sheets, was used to create a range of block copolypeptides of controlled structure. Monomodal molecular weight distributions are observed throughout and molecular weights agree well with predicted values, although polydispersities are generally higher than those observed using more experimentally challenging techniques. This method therefore represents a practical approach to the synthesis of well-defined polypeptides without the requirement for specialized glassware or glove-box techniques.
|Number of pages||10|
|Journal||Journal of Polymer Science, Part A: Polymer Chemistry|
|Publication status||Published - 1 Jun 2009|
- Kinetics (polym.)
- Living polymerization
- Ring-opening polymerization