We report the synthesis and ring-opening metathesis polymerisation (ROMP) of a range of oxygen-containing norbomene derivatives using Grubbs first generation initiator. The ROMP reactions were followed by proton NMR and the identification of propagating species present was facilitated by the addition of excess tricyclohexyl phosphine and copper chloride (a phosphine scavenger), with the intention of further probing the structural, steric, and geometric factors determining the tendency for oxygen atoms in the monomers to complex to the ruthenium centre. (C) 2007 Elsevier B.V. All rights reserved.