Using Clc1ccc(Br)cc1, CCOC(=O)C(C(=O)OCC)=C(C)C to produce CCOC(=O)C(C(=O)OCC)C(C)(C)c1ccc(Cl)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.