Using CCOC(C)=O, O=C(c1ccc(Br)cc1)c1ccc(Br)cc1 to produce CCOC(=O)C=C(c1ccc(Br)cc1)c1ccc(Br)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.