Using COC(C)(C)OC, CCCC[Sn](/C=C/C(O)CC(O)CC(=O)OC)(CCCC)CCCC to produce CCCC[Sn](/C=C/C1CC(CC(=O)OC)OC(C)(C)O1)(CCCC)CCCC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.