2-(4-Chloro-2-nitrophenyl)-9-phenylsulfonyl-9H-carbazole-3-carbaldehyde

In the title compound, C25H15ClN2O6S, the carbazole ring system is essentially planar, with a maximum deviation of 0.152 (3) Å for the C atom to which the 4-chloro-2-nitrophenyl ring is attached. Its mean plane is almost orthogonal to the phenylsulfonyl and nitrophenyl rings, making dihedral angles of 82.64 (14) and 79.89 (13)°, respectively. The N atom of the nitro group deviates by 0.032 (3) Å from the benzene ring to which it is attached. The molecular structure features intramolecular O—H⋯O and C—H⋯O hydrogen bonds, which generate three S(6) ring motifs. In the crystal, molecules are linked by C—H⋯O hydrogen bonds, which generate C(6) and C(9) chains running in the [100] and [010] directions, respectively, forming a two-dimensional network lying parallel to (001). There are also R 4 3(28) supramolecular graph-set ring motifs enclosed within these networks.


Comment
Carbazole and its derivative have become quite attractive compounds owing to their applications in pharmacy and molecular electronics. It has been reported that carbazole derivatives exhibit various biological activities such as antitumor and antioxidative (Itoigawa et al., 2000), and anti-inflammatory and antimutagenic (Ramsewak et al., 1999).
They also exhibit electroactivity and luminenscence and are considered to be potential candidates for electronic applications such as colour displays, organic, semiconductors, laser and solar cells (Friend et al., 1999;Zhang et al., 2004).
The title compound, Fig. 1, comprises a carbazole ring system which is attached to a phenyl-sulfonyl ring, a chloro substituted nitro-phenyl ring, a carbaldehyde group and a hydroxyl group. The carbazole ring system is essentially planar with maximum deviation of -0.152 (3) Å for atom C10 to which is attached the 4-chloro-2-nitro-phenyl ring. Atom O1 significantly deviates from the carbazole ring mean plane by -0.1921 (24) Å. The carbazole ring system is almost orthogonal to the phenyl ring attached to sulfonyl group and to the 4-chloro-2-nitro-phenyl ring with dihedral angles of 82.64 (14)° and 79.89 (13)°, respectively.
In the crystal, molecules are linked by C-H···O hydrogen bonds, which generate C(6) and C(9) chains running in directions [100] and [010], respectively (Table 1 and Fig. 2), and forming a two-dimensional network lying parallel to (001). There are also R 3 4 (28) supramolecular graph-set ring motifs enclosed within these networks.

Experimental
The enamine,

Refinement
The positions of all the H atoms were located in difference electron density maps. They were refined as riding atoms: O -H = = 0.82 Å and C-H = 0.93 Å with Uiso(H) = 1.5Ueq(O-hydroxyl) and = 1.2Ueq(C-aromatic).

Figure 1
The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at 30% probability level. The intramolecular O-H···O and C-H···O hydrogen bonds are shown as dashed lines (see Table 1 for details).

Figure 2
The crystal packing of the title compound viewed along the c axis. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.42 e Å −3 Δρ min = −0.40 e Å −3 Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.