Using CCOCC, O=C(O)C1CCCc2c(Cc3ccc(Cl)cc3)cccc21 to produce O=C(c1ccc(Cl)cc1)c1cccc2c1CCCC2C(=O)O, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.