Using CC(C)(C)OC(=O)N(CCCCO)Cc1ccccc1, O=[Cr](=O)([O-])O[Cr](=O)(=O)[O-] to produce CC(C)(C)OC(=O)N(CCCC(=O)O)Cc1ccccc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.