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

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ISSN: 2414-3146

1-Methyl-3-(2-methyl­phen­yl)-4-phenyl-1H-pyrazolo­[3,4-d]pyrimidine

CROSSMARK_Color_square_no_text.svg

aLaboratoire de Chimie Organique Hétérocyclique, Centre de Recherche Des Sciences des Médicaments, Pôle de Compétence Pharmacochimie, Av Ibn Battouta, BP 1014, Faculté des Sciences, Université Mohammed V, Rabat, Morocco, bLaboratory of Medicinal Chemistry, Faculty of Medicine and Pharmacy, Mohammed V University, Rabat, Morocco, and cDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA
*Correspondence e-mail: elhafi.mohamed1@gmail.com

Edited by L. Van Meervelt, Katholieke Universiteit Leuven, Belgium (Received 23 September 2017; accepted 24 September 2017; online 6 October 2017)

In the title compound, C19H16N4, the pyrazolo­pyrimidine unit is slightly twisted. A combination of π-stacking and offset π-stacking inter­actions forms columns along the b-axis direction.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Among the various classes of nitro­gen containing heterocyclic compounds, pyrazolo­[3,4-d]pyrimidine derivatives display a broad spectrum of biological activities, because of their structural resemblance to purine nucleobases. In recent years, researchers have reported the use of purine derivatives of pyrazolo­[3,4-d]pyrimidine as kinase inhibitors (Diner et al., 2012[Diner, P., Alao, J. P., Soderlund, J., Sunnerhagen, P. & Grotli, M. (2012). J. Med. Chem. 55, 4872-4876.]), anti­viral agents (Bektemirov et al., 2010[Bektemirov, T. A., Chekunova, E. V., Korbukh, I. A., Bulychev, Y. N., Cosimelli, N. G. & Greco, G. (2010). J. Med. Chem. 53, 3954-3963.]) and anti­tubercular agents (Trivedi et al., 2012[Trivedi, A. R., Dholariya, B. H., Vakhariya, C. P., Dodiya, D. K., Ram, H. K., Kataria, V. B., Siddiqui, A. B. & Shah, V. H. (2012). Med. Chem. Res. 21, 1887-1891.]). The present paper is a continuation of our research work devoted to the development of pyrazolo­[3,4-d]pyrimidine derivatives with potential pharmacological activities (El Fal et al., 2013[El Fal, M., Ramli, Y., Essassi, E. M., Saadi, M. & El Ammari, L. (2013). Acta Cryst. E69, o1650.]).

In the title compound, the pyrazolo­pyrimidine moiety is slightly twisted, as indicated by the dihedral angle of 3.19 (6)° between the mean planes through the five- and six-membered rings (Fig. 1[link]). The o-tolyl ring is inclined to the pyrazole ring by 57.26 (6)°, while the phenyl ring is inclined to the pyrimidine ring by 33.04 (6)°. In the crystal, π-stacking inter­actions between pyrimidine rings form centrosymmetric dimers [centroid–centroid = 3.5178 (6) Å], which are formed into stacks along the b-axis direction by offset π-stacking inter­actions between the C2/N2/C3/N3 portions of the centrosymmetrically related dimers [inter­planar spacing = 3.1850 (4) Å; Figs. 2[link] and 3[link]].

[Figure 1]
Figure 1
The mol­ecular structure of the title mol­ecule, with the atom-labelling scheme and displacement ellipsoids drawn at the 50% probability level.
[Figure 2]
Figure 2
Detail of the π-stacking (orange dashed line) and the offset π-stacking (green dashed lines) viewed along the a-axis direction. H atoms have been omitted for clarity.
[Figure 3]
Figure 3
Packing viewed along the b-axis direction, with the π-stacking inter­actions shown as orange dashed lines. H atoms have been omitted for clarity.

Synthesis and crystallization

Under an atmosphere of argon, a mixture of 1-methyl-4-phenyl-1H-pyrazolo­[3,4-d]pyrimidine (0.1 g, 0.47 mmol), 2-iodo­toluene (0.12 ml, 0.94 mmol), Cs2CO3 (0.46 g, 1.42 mmol), K3PO4 (0.25 g, 1.18 mmol), 1,10-phenanthroline (0.034 g, 0.19 mmol) and Pd(OAc)2 (0.021 g, 0.094 mmol) in DMA (3 ml) was flushed with argon and heated to 438 K for 48 h. After completion of the reaction, the mixture was allowed to cool to room temperature and the solvent was removed under reduced pressure. Water (15 ml) was added and the resulting aqueous phase was extracted with CH2Cl2 (3 × 15 ml). The combined organic layers were dried with MgSO4 and concentrated under vacuum. The residue was purified by column chromatography on silica gel (EtOAc/petroleum ether). The title compound was recrystallized from ethanol at room temperature, giving colourless crystals (yield 63%; m.p. 405–407 K).

Refinement

Crystal data, data collection and structure refinement details are presented in Table 1[link].

Table 1
Experimental details

Crystal data
Chemical formula C19H16N4
Mr 300.36
Crystal system, space group Monoclinic, C2/c
Temperature (K) 150
a, b, c (Å) 25.8546 (6), 6.9306 (2), 19.6783 (5)
β (°) 118.658 (1)
V3) 3094.16 (14)
Z 8
Radiation type Cu Kα
μ (mm−1) 0.62
Crystal size (mm) 0.29 × 0.15 × 0.11
 
Data collection
Diffractometer Bruker D8 VENTURE PHOTON 100 CMOS
Absorption correction Multi-scan (SADABS; Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.85, 0.94
No. of measured, independent and observed [I > 2σ(I)] reflections 11463, 3124, 2874
Rint 0.028
(sin θ/λ)max−1) 0.625
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.100, 1.04
No. of reflections 3124
No. of parameters 273
H-atom treatment All H-atom parameters refined
Δρmax, Δρmin (e Å−3) 0.20, −0.20
Computer programs: APEX3 and SAINT (Bruker, 2016[Bruker (2016). APEX3, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXT (Sheldrick, 2015a[Sheldrick, G. M. (2015a). Acta Cryst. A71, 3-8.]), SHELXL2016 (Sheldrick, 2015b[Sheldrick, G. M. (2015b). Acta Cryst. C71, 3-8.]), DIAMOND (Brandenburg & Putz, 2012[Brandenburg, K. & Putz, H. (2012). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Structural data


Computing details top

Data collection: APEX3 (Bruker, 2016); cell refinement: SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: SHELXTL (Bruker, 2016).

1-Methyl-3-(2-methylphenyl)-4-phenyl-1H-pyrazolo[3,4-d]pyrimidine top
Crystal data top
C19H16N4F(000) = 1264
Mr = 300.36Dx = 1.290 Mg m3
Monoclinic, C2/cCu Kα radiation, λ = 1.54178 Å
a = 25.8546 (6) ÅCell parameters from 9566 reflections
b = 6.9306 (2) Åθ = 5.1–74.5°
c = 19.6783 (5) ŵ = 0.62 mm1
β = 118.658 (1)°T = 150 K
V = 3094.16 (14) Å3Column, colourless
Z = 80.29 × 0.15 × 0.11 mm
Data collection top
Bruker D8 VENTURE PHOTON 100 CMOS
diffractometer
3124 independent reflections
Radiation source: INCOATEC IµS micro-focus source2874 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.028
Detector resolution: 10.4167 pixels mm-1θmax = 74.5°, θmin = 5.1°
ω scansh = 3131
Absorption correction: multi-scan
(SADABS; Bruker, 2016)
k = 88
Tmin = 0.85, Tmax = 0.94l = 2422
11463 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037All H-atom parameters refined
wR(F2) = 0.100 w = 1/[σ2(Fo2) + (0.0497P)2 + 1.7251P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
3124 reflectionsΔρmax = 0.20 e Å3
273 parametersΔρmin = 0.20 e Å3
0 restraintsExtinction correction: SHELXL2016 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.00168 (14)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > 2sigma(F2) is used only for calculating R-factors(gt) 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
N10.51451 (4)0.28267 (14)0.60439 (5)0.0309 (2)
N20.54018 (4)0.19678 (13)0.50584 (6)0.0315 (2)
N30.45894 (4)0.22510 (14)0.37751 (6)0.0312 (2)
N40.40026 (4)0.26735 (14)0.34325 (6)0.0319 (2)
C10.45863 (5)0.32694 (15)0.55272 (6)0.0264 (2)
C20.55098 (5)0.21902 (17)0.57827 (7)0.0320 (3)
C30.48400 (5)0.23908 (15)0.45530 (6)0.0277 (2)
H30.5903 (6)0.187 (2)0.6178 (8)0.031 (3)*
C40.48669 (7)0.1722 (2)0.33122 (8)0.0384 (3)
H4A0.4883 (9)0.281 (3)0.3029 (12)0.076 (6)*
H4B0.5266 (8)0.130 (3)0.3651 (10)0.053 (5)*
H4C0.4639 (8)0.067 (3)0.2960 (11)0.062 (5)*
C50.38752 (5)0.31035 (16)0.39930 (6)0.0281 (2)
C60.43977 (5)0.29888 (15)0.47323 (6)0.0262 (2)
C70.42235 (5)0.40674 (16)0.58573 (6)0.0270 (2)
C80.43410 (5)0.34806 (18)0.65990 (6)0.0315 (3)
H80.4642 (6)0.250 (2)0.6866 (8)0.039 (4)*
C90.40480 (6)0.43019 (19)0.69569 (7)0.0361 (3)
H90.4154 (7)0.390 (2)0.7493 (9)0.046 (4)*
C100.36296 (6)0.5724 (2)0.65802 (7)0.0372 (3)
H100.3424 (7)0.628 (2)0.6850 (9)0.047 (4)*
C110.35024 (5)0.63067 (18)0.58415 (7)0.0337 (3)
H110.3201 (7)0.728 (2)0.5559 (9)0.046 (4)*
C120.37979 (5)0.54851 (16)0.54796 (6)0.0291 (3)
H120.3720 (6)0.593 (2)0.4963 (8)0.031 (3)*
C130.32570 (5)0.35885 (17)0.37772 (6)0.0306 (3)
C140.29848 (6)0.51143 (19)0.32611 (7)0.0387 (3)
H140.3218 (6)0.577 (2)0.3046 (8)0.039 (4)*
C150.24060 (7)0.5620 (2)0.30375 (8)0.0486 (4)
H150.2227 (8)0.669 (3)0.2667 (10)0.060 (5)*
C160.20979 (6)0.4615 (2)0.33326 (9)0.0512 (4)
H160.1656 (8)0.497 (3)0.3175 (10)0.062 (5)*
C170.23610 (6)0.3093 (2)0.38378 (9)0.0443 (3)
H170.2145 (7)0.234 (3)0.4087 (10)0.056 (5)*
C180.29390 (5)0.25321 (18)0.40601 (7)0.0340 (3)
C190.31878 (6)0.0783 (2)0.45680 (9)0.0425 (3)
H19A0.3415 (12)0.112 (4)0.5138 (16)0.110 (8)*
H19B0.3482 (10)0.005 (4)0.4467 (13)0.098 (7)*
H19C0.2857 (10)0.014 (4)0.4487 (13)0.098 (7)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0322 (5)0.0299 (5)0.0291 (5)0.0016 (4)0.0136 (4)0.0013 (4)
N20.0344 (5)0.0257 (5)0.0387 (5)0.0015 (4)0.0211 (4)0.0020 (4)
N30.0407 (5)0.0301 (5)0.0301 (5)0.0013 (4)0.0228 (4)0.0008 (4)
N40.0387 (5)0.0320 (5)0.0278 (5)0.0010 (4)0.0183 (4)0.0003 (4)
C10.0314 (5)0.0228 (5)0.0253 (5)0.0030 (4)0.0137 (4)0.0008 (4)
C20.0314 (6)0.0288 (6)0.0354 (6)0.0009 (4)0.0157 (5)0.0031 (5)
C30.0358 (6)0.0213 (5)0.0307 (6)0.0023 (4)0.0196 (5)0.0007 (4)
C40.0526 (8)0.0377 (7)0.0385 (7)0.0001 (6)0.0329 (6)0.0021 (6)
C50.0356 (6)0.0262 (5)0.0239 (5)0.0015 (4)0.0154 (4)0.0008 (4)
C60.0323 (5)0.0225 (5)0.0261 (5)0.0012 (4)0.0160 (4)0.0010 (4)
C70.0308 (5)0.0272 (5)0.0231 (5)0.0043 (4)0.0130 (4)0.0022 (4)
C80.0351 (6)0.0337 (6)0.0242 (5)0.0016 (5)0.0129 (4)0.0004 (4)
C90.0418 (6)0.0436 (7)0.0250 (5)0.0040 (5)0.0177 (5)0.0004 (5)
C100.0423 (7)0.0422 (7)0.0337 (6)0.0018 (5)0.0236 (5)0.0053 (5)
C110.0368 (6)0.0332 (6)0.0333 (6)0.0011 (5)0.0186 (5)0.0003 (5)
C120.0340 (6)0.0290 (5)0.0251 (5)0.0030 (4)0.0148 (4)0.0002 (4)
C130.0338 (6)0.0311 (6)0.0234 (5)0.0003 (4)0.0110 (4)0.0028 (4)
C140.0435 (7)0.0380 (7)0.0291 (6)0.0029 (5)0.0129 (5)0.0030 (5)
C150.0474 (8)0.0447 (8)0.0405 (7)0.0126 (6)0.0106 (6)0.0076 (6)
C160.0358 (7)0.0515 (8)0.0560 (9)0.0066 (6)0.0137 (6)0.0006 (7)
C170.0358 (7)0.0452 (7)0.0501 (8)0.0010 (6)0.0192 (6)0.0023 (6)
C180.0327 (6)0.0351 (6)0.0319 (6)0.0017 (5)0.0137 (5)0.0025 (5)
C190.0400 (7)0.0402 (7)0.0482 (8)0.0028 (6)0.0218 (6)0.0081 (6)
Geometric parameters (Å, º) top
N1—C11.3440 (14)C9—C101.3861 (19)
N1—C21.3462 (16)C9—H90.993 (16)
N2—C21.3235 (16)C10—C111.3879 (17)
N2—C31.3412 (15)C10—H100.991 (16)
N3—C31.3496 (15)C11—C121.3919 (16)
N3—N41.3642 (14)C11—H110.978 (16)
N3—C41.4510 (15)C12—H120.987 (14)
N4—C51.3277 (14)C13—C141.3998 (17)
C1—C61.4109 (15)C13—C181.4004 (17)
C1—C71.4806 (15)C14—C151.387 (2)
C2—H30.964 (14)C14—H140.998 (15)
C3—C61.4111 (15)C15—C161.379 (2)
C4—H4A0.95 (2)C15—H150.984 (19)
C4—H4B0.967 (18)C16—C171.384 (2)
C4—H4C0.982 (19)C16—H161.061 (17)
C5—C61.4363 (15)C17—C181.3961 (18)
C5—C131.4820 (16)C17—H171.043 (18)
C7—C121.3943 (16)C18—C191.5053 (18)
C7—C81.4009 (15)C19—H19A1.01 (3)
C8—C91.3805 (17)C19—H19B1.01 (3)
C8—H80.977 (15)C19—H19C1.02 (3)
C1—N1—C2118.79 (10)C10—C9—H9120.8 (9)
C2—N2—C3111.54 (10)C9—C10—C11119.95 (11)
C3—N3—N4111.12 (9)C9—C10—H10118.2 (9)
C3—N3—C4128.11 (11)C11—C10—H10121.9 (9)
N4—N3—C4120.76 (10)C10—C11—C12120.29 (12)
C5—N4—N3107.33 (9)C10—C11—H11121.3 (9)
N1—C1—C6118.80 (10)C12—C11—H11118.4 (9)
N1—C1—C7115.52 (9)C11—C12—C7120.13 (10)
C6—C1—C7125.67 (10)C11—C12—H12120.5 (8)
N2—C2—N1128.65 (11)C7—C12—H12119.3 (8)
N2—C2—H3116.0 (8)C14—C13—C18119.76 (11)
N1—C2—H3115.4 (8)C14—C13—C5118.51 (11)
N2—C3—N3125.83 (10)C18—C13—C5121.71 (10)
N2—C3—C6126.73 (10)C15—C14—C13120.78 (13)
N3—C3—C6107.40 (10)C15—C14—H14122.0 (8)
N3—C4—H4A109.8 (12)C13—C14—H14117.2 (8)
N3—C4—H4B109.2 (10)C16—C15—C14119.47 (13)
H4A—C4—H4B108.1 (16)C16—C15—H15122.0 (11)
N3—C4—H4C108.7 (10)C14—C15—H15118.5 (11)
H4A—C4—H4C110.8 (16)C15—C16—C17120.23 (13)
H4B—C4—H4C110.1 (15)C15—C16—H16121.3 (10)
N4—C5—C6109.96 (10)C17—C16—H16118.5 (10)
N4—C5—C13118.42 (10)C16—C17—C18121.40 (14)
C6—C5—C13131.61 (10)C16—C17—H17122.0 (10)
C1—C6—C3115.28 (10)C18—C17—H17116.5 (9)
C1—C6—C5140.57 (10)C17—C18—C13118.31 (12)
C3—C6—C5104.15 (9)C17—C18—C19119.00 (12)
C12—C7—C8118.78 (10)C13—C18—C19122.66 (11)
C12—C7—C1122.23 (10)C18—C19—H19A112.7 (16)
C8—C7—C1118.83 (10)C18—C19—H19B113.5 (14)
C9—C8—C7120.92 (11)H19A—C19—H19B104.1 (19)
C9—C8—H8120.2 (8)C18—C19—H19C110.2 (13)
C7—C8—H8118.8 (8)H19A—C19—H19C108.4 (19)
C8—C9—C10119.92 (11)H19B—C19—H19C108 (2)
C8—C9—H9119.2 (9)
C3—N3—N4—C50.49 (13)C6—C1—C7—C1234.01 (16)
C4—N3—N4—C5179.90 (10)N1—C1—C7—C830.76 (15)
C2—N1—C1—C62.10 (15)C6—C1—C7—C8150.72 (11)
C2—N1—C1—C7176.53 (10)C12—C7—C8—C90.82 (17)
C3—N2—C2—N12.75 (17)C1—C7—C8—C9174.62 (11)
C1—N1—C2—N21.98 (18)C7—C8—C9—C100.21 (19)
C2—N2—C3—N3177.90 (10)C8—C9—C10—C110.56 (19)
C2—N2—C3—C60.49 (16)C9—C10—C11—C120.70 (19)
N4—N3—C3—N2176.18 (10)C10—C11—C12—C70.09 (18)
C4—N3—C3—N23.39 (19)C8—C7—C12—C110.66 (17)
N4—N3—C3—C61.64 (12)C1—C7—C12—C11174.61 (10)
C4—N3—C3—C6178.79 (11)N4—C5—C13—C1456.95 (15)
N3—N4—C5—C60.86 (12)C6—C5—C13—C14123.35 (13)
N3—N4—C5—C13178.91 (9)N4—C5—C13—C18121.40 (12)
N1—C1—C6—C34.64 (15)C6—C5—C13—C1858.30 (17)
C7—C1—C6—C3173.83 (10)C18—C13—C14—C151.29 (19)
N1—C1—C6—C5175.06 (13)C5—C13—C14—C15179.68 (12)
C7—C1—C6—C56.5 (2)C13—C14—C15—C160.5 (2)
N2—C3—C6—C14.03 (16)C14—C15—C16—C171.1 (2)
N3—C3—C6—C1178.17 (9)C15—C16—C17—C180.1 (2)
N2—C3—C6—C5175.77 (10)C16—C17—C18—C131.9 (2)
N3—C3—C6—C52.02 (11)C16—C17—C18—C19175.90 (13)
N4—C5—C6—C1178.48 (13)C14—C13—C18—C172.47 (18)
C13—C5—C6—C11.8 (2)C5—C13—C18—C17179.20 (11)
N4—C5—C6—C31.79 (12)C14—C13—C18—C19175.27 (12)
C13—C5—C6—C3177.93 (11)C5—C13—C18—C193.06 (18)
N1—C1—C7—C12144.51 (11)
 

Acknowledgements

Tulane University is gratefully acknowledged for support of the Tulane Crystallography Laboratory.

Funding information

Funding for this research was provided by: NSF–MRI (grant No. 1228232), for the purchase of the diffractometer.

References

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