2,5-Bis[4-(dimethyl-amino)-phen-yl]-3,6-dimethyl-pyrazine

2,7-Bis(2-nitrophenyl)-9-octyl-9H-carbazole

The title compound, C₃₂H₃₁N₃O₄, was obtained in a Suzuki coupling of carbazole diboronic acid and bromo­nitro­benzene. In the crystal, the mol­ecule adopts a non-symmetric conformation. The carbazole ring system is approximately planar [maximum deviation from the least-squares plane = 0.039 (2) Å]. The planes of the carbazole unit and the benzene rings subtend dihedral angles of 48.42 (7) and 41.81 (6)°. The dihedral angles between the planes of the nitro­phenyl rings and the nitro groups are 44.34 (19) and 61.64 (15)°. The crystal is built from two strands of parallel mol­ecules with inter­digitated octyl chains. These strands are symmetry related by a twofold screw axis.

1,4-Dihex-yloxy-2,5-bis-(2-nitro-phen-yl)benzene

The title compound, C₃₀H₃₆N₂O₆, was prepared via twofold Suzuki coupling of a diboronic acid with bromo­nitro­benzene. The mol­ecule is located on a crystallographic inversion centre. The lateral benzene ring and the central ring make a dihedral angle of 48.75 (14)° and the nitro group is twisted by 41.47 (13)° out of the plane of the benzene ring. The nitro and hex­yloxy groups are in close proximity and the hex­yloxy chain adopts an all-anti conformation.

4-[2-(Benzyl-amino)-phen-yl]-2,6-dimethyl-quinoline N-oxide

The title compound, C(24)H(22)N(2)O, was obtained in a two-step procedure from the corresponding 4-(2-iodo-phen-yl)quinoline. The quinoline system is approximately planar [maximum deviation from the least-squares plane = 0.021 (2) Å]. The planes of the quinoline system and the phenyl ring subtend a dihedral angle of 78.08 (8)°. In the crystal, pairs of mol-ecules are connected via a center of symmetry and linked by a pair of angular N-H⋯O hydrogen bond. These dimers form columns oriented along the c axis.

4-Diethyl-amino-3,5-diisopropyl-benzalde-hyde

The title benzaldehyde, C(17)H(27)NO, was prepared via lithia-tion of bromoaniline and reaction with DMF. In the crystal, the molecule adopts a C2-symmetrical conformation; nevertheless, two modes of disorder are present: the orientation of the aldehyde group (occupancy ratio 0.5:0.5) and of symmetry-equivalent ethyl groups [occupancy ratio 0.595 (7):0.405 (7)]. The phenyl-ene ring and the carbonyl group are essentially coplanar [C-C-C-O torsion angle = -179.0 (4)°] but the dihedral angle between the mean planes of the phenyl-ene ring and the amino group = 67.5 (2)°. This and the long [1.414 (3) Å] aniline C-N bond indicate electronic decoupling between the carbonyl and amino groups. The angle sum of 359.9 (2)° around the N atom results from steric compression-induced rehybridization.