Using C=CC[Sn](CCCC)(CCCC)CCCC, COC(=O)Cn1nc(C(F)(F)F)cc1Br to produce C=CCc1cc(C(F)(F)F)nn1CC(=O)OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.