Using CCCCCC, O=C(O)C12CC3CC(C1)CC(c1ccccc1)(C3)C2 to produce COC(=O)C12CC3CC(C1)CC(c1ccccc1)(C3)C2, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.