Eric E. Dueno

2,2′,3,3′-Tetra­methyl-6,6′-biquinoxaline

The molecule of the title compound, C20H18N4, has twofold rotational symmetry. Each aromatic ring of the fused quinoxaline ring system is skewed from the other by 4.93 (7)°. The two quinoxaline units make a dihedral angle of 43.52 (2)°.

IMPROVED SYNTHESIS AND PURIFICATION OF CAVITANDS

6. S. F. Vasilevsky, E. V. Tretyakov and H. D. Verkruijsse, Synth. Commun., 24,1733 (1994). 7. S. F. Vasilevsky and E. V. Tretyakov, Liebigs Ann., 775, (1995). 8. C. G. Overberger, J.-P. Anselme and J. G. Lombardino, in Organic Compounds with Nitrogen-Nitrogen Bonds, the Ronald Press Company, New York, pp. 55-85 (1966). 9. L. G. Fedenok and N. A. Zolnikova, Tetrahedron Lett., 44,5453 (2003). 10. K. Schofield and J. C. E. Simpson,J. Chem. Soc., 520 (1945). 11. K. Schofield and T. Swain,J. Chem. SOC., 2393 (1949). 12. K. Sonogashira, Y. Tohda and N. Hagihara, Tetrahedron Len., 50,4467 (1975).

2,2,3,3′-Tetra­phenyl-7,7′-biquinoxaline

In the crystal structure of the title compound, C40H26N4, molecules reside on crystallographic centers of inversion and are linked via C—H⋯N interactions about inversion centers into one-dimensional chains: longer C—H⋯π(arene) interactions complete the intermolecular interactions.