Using C=CC[Sn](CCCC)(CCCC)CCCC, C[Si](C)(C)c1c(Br)cnc2c1CCO2 to produce C=CCc1cnc2c(c1[Si](C)(C)C)CCO2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.