The crystal structure of 4'-{4-[(2,2,5,5-tetra-methyl-N-oxyl-3-pyrrolin-3-yl)ethyn-yl]phen-yl}-2,2':6',2''-terpyridine.
The terpyridine group of the title compound, C31H27N4O, assumes an all-transoid conformation and is essentially planar with the dihedral angles between the mean planes of the central pyridine and the two outer rings amounting to 3.87 (5) and 1.98 (5)°. The pyrroline-N-oxyl group commonly seen in such nitroxyls is found in the title structure and the mean plane of the pyrroline ring subtends a dihedral angle of 88.44 (7)° to the mean plane of the central pyridine ring. The intra-molecular separation between the nitrogen atom of the central pyridine unit of the terpyridine group and the nitroxyl group is 14.120 (2) Å. In the crystal, the mol-ecules are arranged in layers stacked along [001]. Slipped face-to-face π-π inter-actions between the pyridine rings are observed along this direction with the shortest centroid-centroid distances amounting to 3.700 (1) and 3.781 (1) Å. Furthermore, edge-on C-H⋯π inter-actions between the phenyl-ene rings of neighbouring mol-ecules are observed along this direction. A two-dimensional C-H⋯O hydrogen-bonded network is formed within the (010) plane. The shortest O⋯O separation between neighbouring mol-ecules is 5.412 (3) Å.
University of Bonn, Institute of Physical and Theoretical Chemistry, Wegelerstrasse 12, 53115 Bonn, Germany.
Andreas
A
Meyer
University of Bonn, Institute of Physical and Theoretical Chemistry, Wegelerstrasse 12, 53115 Bonn, Germany.
Jennifer
J
Wiecek
University of Bonn, Institute of Inorganic Chemistry, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany.
Gregor
G
Schnakenburg
University of Bonn, Institute of Physical and Theoretical Chemistry, Wegelerstrasse 12, 53115 Bonn, Germany.
Olav
O
Schiemann
C—H⋯O hydrogen bonding; C—H⋯π interactions; crystal structure; nitrox­ide; nitrox­yl; terpyridine; π–π interactions