Using C=C(OCC)[Sn](CCCC)(CCCC)CCCC, COC(=O)c1ncc(Br)cc1Cl to produce C=C(OCC)c1cnc(C(=O)OC)c(Cl)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.