Using COC(=O)c1[nH]c2cc(NC(=O)OC(C)(C)C)cc3c2c1C=NNC3=O, C=C[Sn](CCCC)(CCCC)CCCC to produce C=Cc1[nH]c2cc(NC(=O)OC(C)(C)C)cc3c2c1C=NNC3=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.