1-Nitro-9H-carbazole

In the title mol­ecule, C₁₂H₈N₂O₂, the nitro group is tilted slightly with respect to the carbazole moiety [angle between the least-squares planes = 4.43 (9)°]. In the crystal, the mol­ecules are connected via pairs of N—H...O hydrogen bonds into dimers with -1 symmetry. The dimers in turn are arranged into layers parallel to (10-1).

Isotypic crystal structures of 2,6-di­bromo-N,N-bis­(4-nitro­phen­yl)aniline and 2,6-di­chloro-N,N-bis­(4-nitro­phen­yl)aniline

The central ternary N atoms in the isotypic crystal structures of the substituted anilines show no sign of pyramidalization.

9-(4-Bromo­phen­yl)-9H-carbazole

In the title mol­ecule, C₁₈H₁₂BrN, the 4-bromo­phenyl ring is inclined to the mean plane of the carbazole moiety (r.m.s. devation = 0.027 Å) by 49.87 (5)°. In the crystal, molecules stack along [001] and are linked by C—H...π interactions forming a corrugated two-dimensional network lying parallel to (100).