Crystal structure and luminescence properties of 2-[(2′,6′-dimethoxy-2,3′-bipyridin-6-yl)oxy]-9-(pyridin-2-yl)-9<i>H</i>- carbazole

Abstract

In the title compound, C29H22N4O3, the carbazole system forms a dihedral angle of 68.45 (3)degrees with the mean plane of the bipyridine ring system. The bipyridine ring system, with two methoxy substituents, is approximately planar (r.m.s. deviation = 0.0670 angstrom), with a dihedral angle of 7.91 (13)degrees between the planes of the two pyridine rings. Intramolecular C-H center dot center dot center dot O/N hydrogen bonds may promote the planarity of the bipyridyl ring system. In the pyridyl-substituted carbazole fragment, the pyridine ring is tilted by 56.65 (4)degrees with respect to the mean plane of the carbazole system (r.m.s. deviation = 0.0191 angstrom). In the crystal, adjacent molecules are connected via C-H center dot center dot center dot O/N hydrogen bonds and C-H center dot center dot center dot pi interactions, resulting in the formation of a three-dimensional (3D) supramolecular network. In addition, the 3D structure contains intermolecular pi-pi stacking interactions, with centroid-centroid distances of 3.5634 (12) angstrom between pyridine rings. The title compound exhibits a high energy gap (3.48 eV) and triplet energy (2.64 eV), indicating that it could be a suitable host material in organic light-emitting diode (OLED) applications.