Using COC(=O)C1CC(CC=CC(C)=O)CN1C(=O)OC(C)(C)C to produce COC(=O)C1CC(CCCC(C)=O)CN1C(=O)OC(C)(C)C, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.