Using COC(=O)c1cccc(Br)c1, CCCC[Sn](CCCC)(CCCC)c1cccnc1C=O to produce COC(=O)c1cccc(-c2cccnc2C=O)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.