Using CN1CCNCC1, CCN1CCN(c2c(OC)c(=O)c2=O)CC1 to produce CCN1CCN(c2c(N3CCN(C)CC3)c(=O)c2=O)CC1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.