Controlled catalyst transfer polycondensation and surface-initiated polymerization of a p-phenyleneethynylene-based monomer

J Am Chem Soc. 2013 Apr 3;135(13):4984-7. doi: 10.1021/ja401740m. Epub 2013 Mar 25.

Abstract

Herein, we describe a catalyst transfer polycondensation that enabled access to well-defined poly(p-phenyleneethynylene) (PPE), a prominent conjugated polymer. Treatment of a stannylated 4-iodophenylacetylene derivative with PhPd(t-Bu3P)Br afforded the corresponding PPE in up to 94% yield. Under optimized conditions, the molecular weight of the polymer increased linearly with monomer consumption, and was controlled by adjusting the initial monomer-to-catalyst ratio. The chain-growth nature of the polymerization reaction was utilized to produce well-defined PPE-containing block copolymers, as well as to grow PPE brushes from silica nanoparticles via a surface-initiated polymerization process.