Using COC(=O)CP(=O)(OC)OC, O=C1CCC(CO)(c2ccc(Br)cc2)CC1 to produce COC(=O)C=C1CCC(CO)(c2ccc(Br)cc2)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.