Using BrC(Br)(Br)Br, COc1cc(C(C)O)c2nn(COCC[Si](C)(C)C)cc2c1 to produce COc1cc(C(C)Br)c2nn(COCC[Si](C)(C)C)cc2c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.