organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 10| October 2015| Pages o766-o767

Crystal structure of 3-methyl-1-phenyl-6-propyl­amino-1H-pyrazolo[3,4-b]pyridine-5-carbo­nitrile

CROSSMARK_Color_square_no_text.svg

aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, bDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, cChemistry and Environmental Division, Manchester Metropolitan University, Manchester M1 5GD, England, dChemistry Department, Faculty of Science, Minia University, 61519 El-Minia, Egypt, eDepartment of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut, Egypt, and fKirkuk University, College of Science, Department of Chemistry, Kirkuk, Iraq
*Correspondence e-mail: shaabankamel@yahoo.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 10 September 2015; accepted 11 September 2015; online 17 September 2015)

In the title compound, C17H17N5, the dihedral angle between the 1H-pyrazolo­[3,4-b]pyridine ring system (r.m.s. deviation = 0.001 Å) and the attached phenyl group is 2.56 (6)°. The propyl­amino side chain has a contorted conformation [Car—N—C—C = −77.97 (16)° and N—C—C—C = −57.37 (17)°]. An intra­molecular C—H⋯N inter­action closes an S(6) ring. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds generate R22(12) loops. Aromatic ππ stacking inter­actions [centroid–centroid distance = 3.5726 (8) Å] are also observed.

1. Related literature

For the chemistry of pyrazolo­[3,4-b]pyridines, see: Häufel & Breitmaier (1974[Häufel, J. & Breitmaier, E. (1974). Angew. Chem. Int. Ed. Engl. 13, 604-606.]); El-emary (2007[El-emary, T. I. (2007). J. Chin. Chem. Soc. 54, 507-518.]); Dodiya et al. (2013[Dodiya, D. K., Trivedi, A. R., Kataria, V. B. & Shah, V. H. (2013). Curr. Org. Chem. 16, 400-417.]). For a similar structure, see: Wang & Zhu (2006[Wang, J. & Zhu, S.-L. (2006). Acta Cryst. E62, o47-o48.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C17H17N5

  • Mr = 291.36

  • Monoclinic, P 21 /c

  • a = 5.1450 (2) Å

  • b = 15.1359 (7) Å

  • c = 19.5828 (9) Å

  • β = 96.547 (4)°

  • V = 1515.05 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 296 K

  • 0.44 × 0.22 × 0.18 mm

2.2. Data collection

  • Agilent Xcalibur Eos Gemini diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2014[Agilent (2014). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]) Tmin = 0.795, Tmax = 1.000

  • 10807 measured reflections

  • 5031 independent reflections

  • 3834 reflections with I > 2σ(I)

  • Rint = 0.025

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.055

  • wR(F2) = 0.143

  • S = 1.03

  • 5031 reflections

  • 205 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.39 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C17—H17⋯N3 0.93 2.33 2.9823 (18) 127
N4—H4N⋯N5i 0.87 (2) 2.20 (2) 3.0326 (17) 160.1 (18)
Symmetry code: (i) -x-1, -y+1, -z+1.

Data collection: CrysAlis PRO (Agilent, 2014[Agilent (2014). CrysAlis PRO. Agilent Technologies Ltd, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Pyrazolo[3,4-b]pyridines (Häufel & Breitmaier, 1974; El-Emary et al., 2007; Dodiya et al., 2013) are attractive targets in organic synthesis and are being extensively investigated because of their wide range of biological activities. We are interested in the synthesis of 6-amino derivatives of 3-methyl-1-phenyl-6-chloro-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile for potential biological interest.

The molecular structure of the title compound is shown in Fig. 1. The 1H-pyrazolo[3,4-b]pyridine ring system (N1—N3/C1—C6) is essentially planar [r.m.s. deviation = 0.001 Å]. It forms a dihedral angle of 2.56 (6) ° with the attached phenyl ring (C12—C17). All bond lengths and bond angles in the title compound are comparable with those of a similar structure previously published (Wang & Zhu, 2006).

In the crystal, pairs of N—H···O hydrogen bonds connect the molecules to each other, forming centrosymmetric dimers with R22(12) motifs (Table 1, Fig. 2). π-π stacking interactions between the dimers [Cg1···Cg3(-1 + x, y, z) = 3.5726 (8) Å] between the centroids of the phenyl and pyrazole rings of the molecules] are also observed.

Related literature top

For the chemistry of pyrazolo[3,4-b]pyridines, see: Häufel & Breitmaier (1974); El-Emary (2007); Dodiya et al. (2013). For a similar structure, see: Wang & Zhu (2006).

Experimental top

A mixture of 3-methyl-1-phenyl-6-chloro-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile (0.268 g, 1 mmol) and propyl amine (1.2 ml, 12 mmol) was heated to 323 K overnight with constant stirring. The reaction mixture was cooled to room temperature and taken up in dichloromethane, washed with 5% aq. NaHCO3, water and then with brine. The organic layer was dried over anhydrous MgSO4 and the solvent was removed under reduced pressure. The crude product was recrystallized from aqueous ethanol to give the title compound as colourless prisms (0.2 g, 69% yield); Rf = 0.25 (hexane:ethyl acetate, 4:1).

Refinement top

The hydrogen atoms attached to carbon atoms were positioned geometrically and constrained to ride on their parent atoms, with carbon hydrogen bond distances of 0.93 - 0.97 Å. Uiso(H) values were set to a multiple of Ueq(C) with 1.5 for CH3 and 1.2 for CH and CH2, respectively. Reflection (-1 1 1) was affected by the beam stop and was omitted from the refinement. The H atom of the NH group were found from a difference Fourier map and refinned freely.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2014); cell refinement: CrysAlis PRO (Agilent, 2014); data reduction: CrysAlis PRO (Agilent, 2014); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the title compound with displacement ellipsoids for non-H atoms drawn at the 50% probability level.
[Figure 2] Fig. 2. A part of N—H···O dimers viewed down b axis. H atoms not involved in H bonding are omitted for clarity.
3-Methyl-1-phenyl-6-propylamino-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile top
Crystal data top
C17H17N5F(000) = 616
Mr = 291.36Dx = 1.277 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2809 reflections
a = 5.1450 (2) Åθ = 4.1–32.4°
b = 15.1359 (7) ŵ = 0.08 mm1
c = 19.5828 (9) ÅT = 296 K
β = 96.547 (4)°Prism, colourless
V = 1515.05 (12) Å30.44 × 0.22 × 0.18 mm
Z = 4
Data collection top
Agilent Xcalibur Eos Gemini
diffractometer
5031 independent reflections
Radiation source: Enhance (Mo) X-ray Source3834 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
Detector resolution: 16.0416 pixels mm-1θmax = 32.7°, θmin = 3.4°
ω scansh = 77
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2014)
k = 2119
Tmin = 0.795, Tmax = 1.000l = 2917
10807 measured reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.055H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.143 w = 1/[σ2(Fo2) + (0.0575P)2 + 0.5443P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
5031 reflectionsΔρmax = 0.39 e Å3
205 parametersΔρmin = 0.19 e Å3
Crystal data top
C17H17N5V = 1515.05 (12) Å3
Mr = 291.36Z = 4
Monoclinic, P21/cMo Kα radiation
a = 5.1450 (2) ŵ = 0.08 mm1
b = 15.1359 (7) ÅT = 296 K
c = 19.5828 (9) Å0.44 × 0.22 × 0.18 mm
β = 96.547 (4)°
Data collection top
Agilent Xcalibur Eos Gemini
diffractometer
5031 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2014)
3834 reflections with I > 2σ(I)
Tmin = 0.795, Tmax = 1.000Rint = 0.025
10807 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0550 restraints
wR(F2) = 0.143H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.39 e Å3
5031 reflectionsΔρmin = 0.19 e Å3
205 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 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 (Å2) top
xyzUiso*/Ueq
N10.1143 (2)0.39657 (8)0.17034 (6)0.0313 (3)
N20.1880 (2)0.35673 (7)0.23372 (5)0.0259 (3)
N30.0577 (2)0.36544 (7)0.34854 (5)0.0240 (3)
N40.1030 (2)0.38566 (8)0.45253 (6)0.0290 (3)
N50.6220 (3)0.54182 (8)0.43046 (6)0.0335 (3)
C10.0775 (3)0.45129 (9)0.17907 (7)0.0307 (4)
C20.0384 (2)0.38812 (8)0.28219 (6)0.0235 (3)
C30.1361 (3)0.44952 (8)0.24825 (7)0.0263 (3)
C40.3133 (3)0.49088 (8)0.28667 (7)0.0275 (3)
C50.3023 (2)0.46884 (8)0.35533 (7)0.0250 (3)
C60.1121 (2)0.40572 (8)0.38532 (6)0.0238 (3)
C70.0940 (3)0.32792 (9)0.48825 (7)0.0305 (4)
C80.0446 (3)0.22989 (10)0.47497 (8)0.0337 (4)
C90.2167 (4)0.19810 (12)0.49344 (10)0.0464 (5)
C100.4806 (3)0.50939 (8)0.39696 (7)0.0264 (3)
C110.2089 (4)0.50428 (11)0.12099 (8)0.0445 (5)
C120.3868 (2)0.29171 (8)0.23836 (7)0.0259 (3)
C130.5115 (3)0.27319 (9)0.18042 (8)0.0340 (4)
C140.7117 (3)0.21152 (10)0.18464 (9)0.0386 (4)
C150.7886 (3)0.16777 (9)0.24520 (9)0.0356 (4)
C160.6611 (3)0.18531 (10)0.30210 (8)0.0334 (4)
C170.4609 (3)0.24712 (9)0.29935 (7)0.0301 (4)
H40.434100.531700.266800.0330*
H4N0.206 (4)0.4127 (12)0.4777 (10)0.041 (5)*
H7A0.101500.338800.537300.0370*
H7B0.263400.343100.474300.0370*
H8A0.054600.217900.426700.0400*
H8B0.182200.196300.501300.0400*
H9A0.223100.205200.541900.0700*
H9B0.238800.136800.481500.0700*
H9C0.354200.232000.468700.0700*
H11A0.204300.565700.133300.0670*
H11B0.387500.485500.111200.0670*
H11C0.119800.495800.081000.0670*
H130.460600.302100.139100.0410*
H140.795300.199500.146000.0460*
H150.924500.127000.247800.0430*
H160.710300.155200.342900.0400*
H170.377100.258500.338100.0360*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0380 (6)0.0317 (6)0.0259 (5)0.0000 (5)0.0115 (5)0.0002 (4)
N20.0282 (5)0.0285 (5)0.0227 (5)0.0009 (4)0.0100 (4)0.0025 (4)
N30.0231 (5)0.0257 (5)0.0243 (5)0.0018 (4)0.0080 (4)0.0049 (4)
N40.0303 (6)0.0340 (6)0.0244 (5)0.0061 (5)0.0104 (4)0.0027 (4)
N50.0361 (6)0.0338 (6)0.0319 (6)0.0063 (5)0.0102 (5)0.0022 (5)
C10.0382 (7)0.0286 (6)0.0268 (6)0.0021 (5)0.0102 (5)0.0009 (5)
C20.0238 (5)0.0235 (5)0.0245 (6)0.0039 (4)0.0080 (4)0.0044 (4)
C30.0312 (6)0.0229 (5)0.0260 (6)0.0025 (5)0.0089 (5)0.0014 (4)
C40.0302 (6)0.0222 (5)0.0310 (6)0.0000 (5)0.0078 (5)0.0006 (5)
C50.0249 (6)0.0221 (5)0.0293 (6)0.0007 (4)0.0085 (5)0.0039 (4)
C60.0231 (5)0.0237 (5)0.0256 (6)0.0025 (4)0.0072 (4)0.0047 (4)
C70.0281 (6)0.0374 (7)0.0259 (6)0.0016 (5)0.0030 (5)0.0027 (5)
C80.0314 (7)0.0361 (7)0.0338 (7)0.0048 (6)0.0051 (5)0.0022 (6)
C90.0460 (9)0.0489 (9)0.0465 (9)0.0075 (8)0.0150 (8)0.0028 (7)
C100.0280 (6)0.0238 (5)0.0282 (6)0.0001 (5)0.0064 (5)0.0017 (5)
C110.0614 (11)0.0417 (8)0.0317 (8)0.0091 (8)0.0110 (7)0.0074 (6)
C120.0242 (6)0.0250 (6)0.0298 (6)0.0049 (5)0.0093 (5)0.0081 (5)
C130.0412 (8)0.0314 (7)0.0326 (7)0.0002 (6)0.0179 (6)0.0048 (5)
C140.0431 (8)0.0327 (7)0.0443 (8)0.0004 (6)0.0240 (7)0.0092 (6)
C150.0299 (7)0.0293 (6)0.0492 (9)0.0002 (5)0.0110 (6)0.0110 (6)
C160.0293 (7)0.0345 (7)0.0363 (7)0.0008 (5)0.0033 (5)0.0070 (6)
C170.0263 (6)0.0359 (7)0.0292 (6)0.0001 (5)0.0083 (5)0.0079 (5)
Geometric parameters (Å, º) top
N1—N21.3930 (15)C13—C141.386 (2)
N1—C11.3143 (18)C14—C151.376 (2)
N2—C21.3732 (15)C15—C161.382 (2)
N2—C121.4148 (15)C16—C171.388 (2)
N3—C21.3366 (15)C4—H40.9300
N3—C61.3406 (15)C7—H7A0.9700
N4—C61.3463 (17)C7—H7B0.9700
N4—C71.4556 (18)C8—H8A0.9700
N5—C101.144 (2)C8—H8B0.9700
C1—C31.421 (2)C9—H9A0.9600
C1—C111.490 (2)C9—H9B0.9600
C2—C31.4055 (18)C9—H9C0.9600
C3—C41.395 (2)C11—H11A0.9600
C4—C51.3802 (19)C11—H11B0.9600
N4—H4N0.87 (2)C11—H11C0.9600
C5—C101.4330 (19)C13—H130.9300
C5—C61.4437 (16)C14—H140.9300
C7—C81.523 (2)C15—H150.9300
C8—C91.510 (3)C16—H160.9300
C12—C171.3869 (19)C17—H170.9300
C12—C131.394 (2)
N2—N1—C1106.80 (11)C3—C4—H4121.00
N1—N2—C2110.43 (10)C5—C4—H4121.00
N1—N2—C12118.66 (10)N4—C7—H7A109.00
C2—N2—C12130.87 (10)N4—C7—H7B109.00
C2—N3—C6115.13 (10)C8—C7—H7A109.00
C6—N4—C7123.36 (11)C8—C7—H7B109.00
N1—C1—C3110.86 (12)H7A—C7—H7B108.00
N1—C1—C11121.48 (13)C7—C8—H8A109.00
C3—C1—C11127.65 (14)C7—C8—H8B109.00
N2—C2—N3126.71 (11)C9—C8—H8A109.00
N2—C2—C3106.27 (11)C9—C8—H8B109.00
N3—C2—C3127.03 (11)H8A—C8—H8B108.00
C1—C3—C2105.65 (12)C8—C9—H9A109.00
C1—C3—C4136.75 (13)C8—C9—H9B109.00
C2—C3—C4117.60 (12)C8—C9—H9C110.00
C3—C4—C5117.40 (12)H9A—C9—H9B109.00
C7—N4—H4N116.6 (13)H9A—C9—H9C109.00
C6—N4—H4N119.6 (13)H9B—C9—H9C109.00
C4—C5—C10119.53 (11)C1—C11—H11A109.00
C4—C5—C6120.45 (11)C1—C11—H11B109.00
C6—C5—C10120.02 (12)C1—C11—H11C109.00
N4—C6—C5119.56 (11)H11A—C11—H11B109.00
N3—C6—C5122.37 (11)H11A—C11—H11C110.00
N3—C6—N4118.07 (11)H11B—C11—H11C109.00
N4—C7—C8114.17 (12)C12—C13—H13120.00
C7—C8—C9113.92 (13)C14—C13—H13120.00
N5—C10—C5179.66 (15)C13—C14—H14120.00
N2—C12—C13118.95 (12)C15—C14—H14120.00
C13—C12—C17119.75 (12)C14—C15—H15120.00
N2—C12—C17121.30 (12)C16—C15—H15120.00
C12—C13—C14119.66 (14)C15—C16—H16119.00
C13—C14—C15120.95 (15)C17—C16—H16119.00
C14—C15—C16119.09 (14)C12—C17—H17120.00
C15—C16—C17121.11 (14)C16—C17—H17120.00
C12—C17—C16119.43 (13)
C1—N1—N2—C20.22 (14)N1—C1—C3—C20.00 (16)
C1—N1—N2—C12177.73 (11)N3—C2—C3—C1179.11 (12)
N2—N1—C1—C30.13 (15)N2—C2—C3—C10.15 (14)
N2—N1—C1—C11178.72 (13)N3—C2—C3—C41.3 (2)
C2—N2—C12—C170.2 (2)N2—C2—C3—C4179.47 (12)
N1—N2—C12—C17177.28 (12)C1—C3—C4—C5179.97 (16)
C12—N2—C2—N33.4 (2)C2—C3—C4—C50.51 (19)
N1—N2—C2—C30.23 (13)C3—C4—C5—C60.41 (18)
N1—N2—C2—N3179.03 (11)C3—C4—C5—C10179.87 (12)
C2—N2—C12—C13179.14 (12)C10—C5—C6—N3179.49 (11)
C12—N2—C2—C3177.40 (12)C4—C5—C6—N30.79 (18)
N1—N2—C12—C133.40 (17)C4—C5—C6—N4179.43 (12)
C2—N3—C6—C50.14 (17)C10—C5—C6—N40.29 (17)
C6—N3—C2—C30.91 (18)N4—C7—C8—C957.37 (17)
C2—N3—C6—N4179.92 (11)N2—C12—C13—C14178.16 (12)
C6—N3—C2—N2180.00 (12)C17—C12—C13—C141.2 (2)
C7—N4—C6—C5175.32 (11)N2—C12—C17—C16178.48 (12)
C7—N4—C6—N34.89 (18)C13—C12—C17—C160.8 (2)
C6—N4—C7—C877.97 (16)C12—C13—C14—C150.4 (2)
C11—C1—C3—C2178.77 (14)C13—C14—C15—C160.8 (2)
C11—C1—C3—C40.7 (3)C14—C15—C16—C171.1 (2)
N1—C1—C3—C4179.50 (16)C15—C16—C17—C120.3 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C17—H17···N30.932.332.9823 (18)127
N4—H4N···N5i0.87 (2)2.20 (2)3.0326 (17)160.1 (18)
Symmetry code: (i) x1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C17—H17···N30.932.332.9823 (18)127
N4—H4N···N5i0.87 (2)2.20 (2)3.0326 (17)160.1 (18)
Symmetry code: (i) x1, y+1, z+1.
 

Acknowledgements

JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer. HHMA is also gratful to Professor Talaat I. El-emary, Assiut University, for his advice on the synthetic method.

References

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Volume 71| Part 10| October 2015| Pages o766-o767
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