Using NCCN, ClCc1ccc2ccccc2n1 to produce c1ccc2nc(CN(CCN(Cc3ccc4ccccc4n3)Cc3ccc4ccccc4n3)Cc3ccc4ccccc4n3)ccc2c1, please predict the solvent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.