Using COC[P+](c1ccccc1)(c1ccccc1)c1ccccc1, COC(=O)C(=O)c1cccc(Cl)c1C to produce COC=C(C(=O)OC)c1cccc(Cl)c1C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.