Using OCCCCc1ccccc1, Oc1c(Cl)cc(OCC=C(Cl)Cl)cc1Cl to produce ClC(Cl)=CCOc1cc(Cl)c(OCCCCc2ccccc2)c(Cl)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.