Using COc1cc(CC2C(=O)C=CCC2(C)C)c(C(C)(C)C)c(O[SiH](C)C)c1Br to produce COc1cc(CC2C(=O)CCCC2(C)C)c(C(C)(C)C)c(O[SiH](C)C)c1Br, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.