N-(2-Amino-ethyl)-5-(dimethyl-amino)naphthalene-1-sulfonamide

5-Methyl-1,3-phenyl-ene bis-[5-(di-methyl-amino)-naphthalene-1-sulfonate]: crystal structure and DFT calculations

The title compound, C31H30N2S2O6, possesses crystallographically imposed twofold symmetry with the two C atoms of the central benzene ring and the C atom of its methyl substituent lying on the twofold rotation axis. The two dansyl groups are twisted away from the plane of methyl-phenyl bridging unit in opposite directions. The three-dimensional arrangement in the crystal is mainly stabilized by weak hydrogen bonds between the sulfonyl oxygen atoms and the hydrogen atoms from the N-methyl groups. Stacking of the dansyl group is not observed. From the DFT calculations, the HOMO-LUMO energy gap was found to be 2.99 eV and indicates n→π* and π→π* transitions within the mol-ecule.

The crystal structure of 2-[5-(di-methyl-amino)-naphthalene-1-sulfonamido]-phenyl 5-(di-methyl-amino)-naphthalene-1-sulfonate

The complete mol-ecule of the title compound, C30H29N3O5S2, is generated by a crystallographic twofold axis: the O atom and NH group attached to the central benzene ring are statistically disordered. The dihedral angle between the naphthalene ring system and the central benzene ring is 52.99 (6)°, while the pendant naphthalene ring systems subtend a dihedral angle of 68.17 (4)°. An intra-molecular C-H⋯O hydrogen bond closes an S(6) ring. In the crystal, the mol-ecules are linked by weak C-H⋯O hydrogen bonds.