Using COC(=O)C1=C(c2cc(F)c(F)cc2F)CCC2(C1)OCCO2 to produce COC(=O)C1CC2(CCC1c1cc(F)c(F)cc1F)OCCO2, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.