Using CCOC(=O)C(=O)OCC, CCC1=CC(CC)([Mg]Br)CC(CC)=C1 to produce CCOC(=O)C(=O)C1(CC)C=C(CC)C=C(CC)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.