Crystal structure of 4-(2-azidophenyl)-5-benzoyl-2-(1H-indol-3-yl)-1H-pyrrole-3-carbonitrile

In the title compound, C26H16N6O, the dihedral angles between the central pyrrole ring and the pendant indole ring system (r.m.s. deviation = 0.027 Å) and the azide-bearing benzene ring are 37.56 (8) and 51.62 (11)°, respectively. The azide group is almost coplanar with its attached benzene ring [C—C—N—N = 3.8 (3)°]. The benzoyl benzene ring is disordered over two orientations twisted with respect to each other by 9.29 (8)° in a 0.514 (2):0.486 (2) ratio. In the crystal, inversion dimers linked by pairs of Np—H⋯O (p = pyrrole) hydrogen bonds generate R 2 2(10) loops. A second inversion dimer arises from a pair of Ni—H⋯Nc (i = indole and c = cyanide) hydrogen bonds, which generates an R 2 2(16) loop. Together, the hydrogen bonds lead to [011] chains in the crystal.

In the title compound, C 26 H 16 N 6 O, the dihedral angles between the central pyrrole ring and the pendant indole ring system (r.m.s. deviation = 0.027 Å ) and the azide-bearing benzene ring are 37.56 (8) and 51.62 (11) , respectively. The azide group is almost coplanar with its attached benzene ring [C-C-N-N = 3.8 (3) ]. The benzoyl benzene ring is disordered over two orientations twisted with respect to each other by 9.29 (8) in a 0.514 (2):0.486 (2) ratio. In the crystal, inversion dimers linked by pairs of N p -HÁ Á ÁO (p = pyrrole) hydrogen bonds generate R 2 2 (10) loops. A second inversion dimer arises from a pair of N i -HÁ Á ÁN c (i = indole and c = cyanide) hydrogen bonds, which generates an R 2 2 (16) loop. Together, the hydrogen bonds lead to [011] chains in the crystal.
Keywords: crystal structure; indole derivatives; pyrrole-3-carbonitrile; hydrogen bonding.   Table 1 Hydrogen-bond geometry (Å , ). supporting information . ratio v/v, 5 ml) to give pure compounds. The compound was recrystallized from methanol to yield yellow crystals. The yield of the isolated product was 91%. Yellow blocks were obtained by slow evaporation of a solution of the title compound in methanol at room temperature.

S2. Refinement
All H atoms were fixed geometrically and allowed to ride on their parent C atoms, with C-H distances fixed in the range 0.93-0.97 Å with U iso (H) = 1.5U eq (C) for methyl H atoms and 1.2U eq (C) for all other H atoms.

Figure 1
The molecular structure of the title compound, with displacement ellipsoids drawn at 30% probability level.

Figure 2
The crystal packing of the title compound viewed along c axis. Hydrogen atoms are omitted for clarity. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.21 e Å −3 Δρ min = −0.25 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq Occ.