Using C=C[Sn](CCCC)(CCCC)CCCC, CC(C)(C)C(=O)Nc1ccc(Br)cn1 to produce C=Cc1ccc(NC(=O)C(C)(C)C)nc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.