N-(1H-Indazol-5-yl)-4-methoxybenzenesulfonamide

In the title compound, C14H13N3O3S, the fused ring system is almost planar, the largest deviation from the mean plane being 0.023 (2) Å, and makes a dihedral angle of 47.92 (10)° with the benzene ring of the benzenesulfonamide moiety. In the crystal, molecules are connected through N—H⋯O hydrogen bonds and weak C—H⋯O contacts, forming a two-dimensional network which is parallel to (010).

The molecule of the title compound is built up from two fused five-and six-membered rings (N1/N2/C1 to C7) linked to the 4-methoxybenzenesulfonamide group, as shown in Fig. 1. The fused ring system is almost planar, with the maximum deviation of -0.023 (2) Å arising from atom C1. Moreover, the dihedral angle between the indazole system and the plan through the atoms forming the benzene ring (C8 to C13) is 47.92 (10)°.
In the crystal, molecules are connected through N-H···O hydrogen bonds and weak C-H···O contacts, forming a twodimensional network nearly parallel to (0 1 0) as shown in Fig.2 and Table 1.

Experimental
A mixture of 5-nitroindazole (216 mg, 1.22 mmol) and anhydrous SnCl 2 (1.1 g, 6.1 mmol) in 25 ml of absolute ethanol was heated at 333 K for 6 h. After reduction, the starting material disappeared and the solution was allowed to cool down.
The pH was made slightly basic (pH 7-8) by addition of 5% aqueous potassium bicarbonate before extraction with ethyl acetate. The organic phase was washed with brine and dried over magnesium sulfate. The solvent was removed to afford the amine, which was immediately dissolved in pyridine (5 ml) and then reacted with 4-methoxybenzenesulfonyl chloride (1.25 mmol) at room temperature for 24 h. After the reaction mixture was concentrated in vacuo, the resulting residue was purified by flash chromatography (eluted with ethyl acetate: hexane 2:8, yield: 54%, m.p.: 437 K). The title compound was recrystallized from ethanol.

Refinement
H atoms were located in a difference map and treated as riding with C-H = 0.96 Å, C-H = 0.93 Å, and N-H = 0.89 Å for methyl, aromatic CH and NH, respectively. Thermal parameters for hydrogen atoms were refined as U iso (H) = 1.2 U eq (C) (aromatic CH, NH) and U iso (H) = 1.5 U eq (C) for the methyl group.    where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.26 e Å −3 Δρ min = −0.32 e Å −3 Special details Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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.  (3) O2-S1 1.4361 (14)