Using COC(=O)C1(CCC(C)C)C(OC)=CCc2ccccc21, O=[Cr](=O)([O-])O[Cr](=O)(=O)[O-] to produce COC(=O)C1(CCC(C)C)C(OC)=CC(=O)c2ccccc21, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.