Narrowly distributed homotelechelic polymers in 30 minutes: Using fast in-situ pre-functionalised ROMP initiators.

Today's olefin metathesis catalysts show high reactivity, selectivity and functional group tolerance and allow the design of new syntheses of precisely functionalised polymers. Here we describe a general "one-pot" synthesis for narrow polydispersity bis-end-functional (=homotelechelic) ROMP polymers exploiting the propagating ruthenium complex' inherent selectivity for strained norbornenes over acyclic internal olefins. This approach represents a straightforward general method of homotelechelic polymers carrying almost any functional end group (within the limitations of the catalyst's functionality tolerance). Complete pre-functionalisation of the initiator is realised in-situwithin minutes and without the need of further purification steps. The excess acyclic olefin re-enters the catalytic cycle after monomer consumption is complete giving a homotelechelic polymer. ¹H-NMR spectroscopic and MALDI-ToF-MS analysis show highly efficient end group functionalisation.)