4-(4-Bromo­phen­yl)-4,5,6,7-tetra­hydro-3-methyl-6-oxo-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile ethanol solvate

Xue-Sen Fan; Xiao-Yan Li; Xia Wang; Dong-Fang Li; Xin-Ying Zhang

doi:10.1107/S1600536808028638

. 2008 Sep 13;64(Pt 10):o1925. doi: 10.1107/S1600536808028638

4-(4-Bromophenyl)-4,5,6,7-tetrahydro-3-methyl-6-oxo-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile ethanol solvate

Xue-Sen Fan ^a,^*, Xiao-Yan Li ^a, Xia Wang ^a, Dong-Fang Li ^a, Xin-Ying Zhang ^a

PMCID: PMC2959421 PMID: 21201133

Abstract

In the structure of the title compound, C₂₀H₁₅BrN₄O·C₂H₆O, the hydrogenated pyridinone ring adopts an envelope conformation. The dihedral angle between the bromo-substituted phenyl ring and the pyrazole ring is 79.6 (1)°, and that between the non-substituted phenyl ring and the pyrazole ring is 51.2 (1)°. In the crystal structure, molecules are linked via intermolecular N—H⋯O and O—H⋯N hydrogen bonds. A short intermolecular N⋯Br contact [3.213 (4) Å] is present in the crystal structure.

Related literature

For general background, see: Falcó et al. (2005 ▶); Kung & Wager (2007 ▶).

Experimental

Crystal data

C₂₀H₁₅BrN₄O·C₂H₆O
M _r = 453.34
Monoclinic,
a = 21.871 (9) Å
b = 9.209 (4) Å
c = 10.552 (5) Å
β = 90.370 (5)°
V = 2125.4 (15) Å³
Z = 4
Mo Kα radiation
μ = 1.96 mm⁻¹
T = 295 (2) K
0.31 × 0.24 × 0.14 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1997 ▶) T _min = 0.586, T _max = 0.770
10428 measured reflections
3947 independent reflections
2414 reflections with I > 2σ(I)
R _int = 0.035

Refinement

R[F ² > 2σ(F ²)] = 0.046
wR(F ²) = 0.121
S = 1.01
3947 reflections
265 parameters
H-atom parameters constrained
Δρ_max = 0.53 e Å⁻³
Δρ_min = −0.51 e Å⁻³

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1997 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808028638/xu2452sup1.cif

e-64-o1925-sup1.cif^{(22.1KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808028638/xu2452Isup2.hkl

e-64-o1925-Isup2.hkl^{(193.5KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯N1ⁱ	0.82	2.06	2.874 (4)	171
N3—H3D⋯O2	0.97	1.84	2.786 (3)	166

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Symmetry code: (i) Inline graphic .

Acknowledgments

This work was supported by the National Natural Science Foundation of China (No. 20772025) and the Program for Science and Technology Innovation Talents in Universities of Henan Province (No. 2008HASTIT006).

supplementary crystallographic information

Comment

Pyrazolo[3,4-b]pyridine-6-ones as a subunit of pyrazolo[3,4-b]pyridine acted as potential hypnotic drugs in many cases (Falcó et al., 2005). Hydrogenated pyrazolo[3,4-b]pyridin-6-ones have been found with good biological activity such as GSK-3 inhibitors (Kung et al., 2007) and have the potential to be used as novel building blocks to construct new nitrogen-containing molecules. The title compound is one of the hydrogenated pyrazolo[3,4-b]pyridin-6-one derivatives. Its crystal structure is presented here.

In the title compound (Fig. 1) there are four rings, three planar rings and one nonplanar hydrogenated pyridinone ring. The hydrogenated pyridinone ring is fused to the pyrazole ring and adopts an envelope conformation with C4 at flap position. The dihedral angle between the bromo-substituted benzene ring and the pyrazole ring is 79.6 (1)° and that between the non-substituted phenyl ring and the pyrazole ring is 51.2 (1)°.

Intermolecular N—H···O and O—H···N hydrogen bonding (Table 1) and the weak intermolecular Br1···N4ⁱ contact present in the crystal structure [symmetry code: (i) 1-x, -1/2+y, 1/2-z].

Experimental

4-Bromobenzaldehyde (1 mmol) and ethyl cyanoacetate (1 mmol) were added to 1 ml of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF₄]). The mixture was stirred at 353 K until the disappearance of bromobenzaldehyde. Upon cooling to room temperature, 5-amino-3-methyl-1-phenylpyrazole (1 mmol) was added and the mixture was stirred at room temperature for a certain period of time to complete the reaction (monitored by TLC). The reaction time was 9 h totally. Upon completion, the product was not separated from the reaction system; instead, 4 ml of ethanol was added. Single crystals of the title compound were obtained by slow evaporation of the solvent.