Crystal structure of (2-hydroxy-5-methylphenyl)(3-methyl-1-phenyl-1H-pyrazolo[3,4-b]pyridin-5-yl)methanone

In the title compound, C21H17N3O2, the 2-hydroxy-5-methylphenyl ring and the phenyl ring are inclined to the mean plane of the pyrazolopyridine moiety (r.m.s. deviation = 0.013 Å) by 52.89 (9) and 19.63 (8)°, respectively, and to each other by 42.83 (11)°. In the molecule, there are intramolecular O—H⋯O and C—H⋯N hydrogen bonds, both enclosing an S(6) ring motif. In the crystal, molecules stack along the c-axis direction, forming columns within which there are a number of π–π interactions [the inter-centroid distances vary from 3.5278 (10) to 3.8625 (10) Å]. The columns are linked by C—H⋯π interactions, forming slabs parallel to (100).


S2. Synthesis and crystallization
To a mixture of 3-formylchromone and 5-amino-3-methyl-1-phenyl pyrazole in ethanol, was added a catalytic amount of In(OTf) 3 and the resulting mixture was refluxed for ca. 20 min. The precipitate formed was filtered and dried under vacuum to afford the pure title product (yield: 87%). It was recrystallized from ethanol and DMSO-D 6 by slow evaporation over 48 h, giving colourless block-like crystals.

S3. Refinement
Crystal data, data collection and structure refinement details are summarized in Table 2 The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level. Intramolecular 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. The O-H···O and C-H···π interactions are shown as dashed lines (see Table 1 for details).

supporting information sup-3
Acta Cryst. (2015). E71, o501-o502 where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.20 e Å −3 Δρ min = −0.18 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 C1 0.05588 (