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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 1| January 2008| Page o212
https://doi.org/10.1107/S1600536807064318

2-Methyl-5-(4-tol­yl)-7-(tri­fluoro­meth­yl)pyrazolo[1,5-a]pyrimidine

Clarissa P. Frizzo,a Patrick T. Campos,a Mara R. B. Marzari,a Pablo Machadoa and Marcos A. P. Martinsa*

aNúcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
*Correspondence e-mail: mmartins@base.ufsm.br

(Received 14 November 2007; accepted 29 November 2007; online 6 December 2007)

In the title compound, C15H12F3N3, the pyrazolo[1,5-a]pyrimidine system ring is essentially planar with a maximum deviation from the mean plane of 0.014 (1) Å. The 4-tolyl group makes a dihedral angle of 14.1 (1)° with the pyrazolo[1,5-a]pyrimidine ring system. The crystal packing is stabilized mainly by van der Waals forces.

Related literature

For related pyrazolopyrimidine compounds, see: Wen et al. (2004[Wen, L.-R., Wang, S.-W., Xu, H.-Z., Zhang, X.-L., Li, M. & Liu, J.-H. (2004). Acta Cryst. E60, o1294-o1295.], 2005[Wen, L.-R., Wang, S.-W., Li, M. & Guo, W.-S. (2005). Acta Cryst. E61, o1459-o1460.]); Oliveira-Campos et al. (2006[Oliveira-Campos, A. M. F., Rodrigues, L. M., Kaja, M., Guilardi, S., Franca, E. de F. & Ellena, J. (2006). Acta Cryst. E62, o5246-o5248.]). For related literature and the synthetic procedure, see: Martins et al. (2004[Martins, M. A. P., Cunico, W., Pereira, C. M. P., Sinhorin, A. P., Flores, A. F. C., Bonacorso, H. G. & Zanatta, N. (2004). Curr. Org. Synth. 1, 391-403 and references therein.], 2006[Martins, M. A. P., Cunico, W., Scapin, E., Emmerich, D. J., Fiss, G. F., Rosa, F. A., Bonacorso, H. B., Zanatta, N. & Flores, A. F. C. (2006). Lett. Org. Chem. 3, 358-362.]). For the pharmacological activity, see: Almanza et al. (2001[Almanza, C., Arriba, F. A., Cavalcanti, F. L., Gómez, L. A., Miralle, A., Merlos, M., Rafanell, J. G. & Forn, J. (2001). J. Med. Chem. 44, 350-361.]); Novinson et al. (1977[Novinson, T., Robins, R. K. & Matthews, T. R. (1977). J. Med. Chem. 20, 296-299.]); George (2001[George, C. F. P. (2001). Lancet, 358, 1623-1626.]).

[Scheme 1]

Experimental

Crystal data

  • C15H12F3N3

  • Mr = 291.28

  • Triclinic, [P \overline 1]

  • a = 4.8715 (2) Å

  • b = 11.2655 (5) Å

  • c = 13.5584 (6) Å

  • α = 110.225 (3)°

  • β = 96.808 (3)°

  • γ = 99.835 (3)°

  • V = 675.13 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 293 (2) K

  • 0.98 × 0.21 × 0.20 mm
Data collection

  • Bruker X8 APEXII diffractometer

  • Absorption correction: multi-scan (XPREP; Bruker, 2006[Bruker (2006). APEX2 (Version 2.1), SAINT (Version 7.34A) and XPREP (Version 2005/4). Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.874, Tmax = 0.977

  • 16787 measured reflections

  • 3757 independent reflections

  • 2200 reflections with I > 2σ(I)

  • Rint = 0.040
Refinement

  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.227

  • S = 1.05

  • 3757 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.40 e Å−3

  • Δρmin = −0.45 e Å−3

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 (Version 2.1), SAINT (Version 7.34A) and XPREP (Version 2005/4). Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 (Version 2.1), SAINT (Version 7.34A) and XPREP (Version 2005/4). Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97 and SHELXS97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXL97 and SHELXS97. University of Göttingen, Germany.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536807064318/xu2373sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807064318/xu2373Isup2.hkl

checkCIF report


Comment top

Pyrazolopyrimidine derivatives are important biologically active compounds obtained to showed anti-inflammatory (PGHS-2 inhibitors) (Almanza et al., 2001) and antifungal activities (cAMP phosphodiasterase and xanthine oxidase inhibitors) (Novinson et al., 1977). In addition, this scaffold have been found to be integral parts of potent nonbenzodiazepine hypnotic agents (George, 2001). Zaleplon is one example of a pyrazolopyrimidine derivative in clinical use (George, 2001). In a continuation of our study about synthesis and reactivity of pyrazolopyrimidine (Martins et al., 2006) as well as trihalomethylated compounds (Martins et al., 2004) we reported, in this communication, the crystal structure of the title compound, 2-methyl-5-(4-tolyl)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine.

The analysis showed that the pyrazolo[1,5-a]pyrimidine ring is essentially planar with maximum deviation from mean plane of 0.014 (1) Å. The 4-tolyl group makes a dihedral angle of 14.1 (1)° with respect to the pyrazolo[1,5-a]pyrimidine ring system. In addition, the dihedral angle between the five-membered ring and the fused six-membered ring is 0.84 (1)° in accordance with previous reports (Wen et al., 2004; Wen et al., 2005; Oliveira-Campos et al., 2006). The crystal packing is stabilized mainly by van der Waals forces.

Related literature top

For related pyrazolopyrimidine compounds, see Wen et al. (2004, 2005); Oliveira-Campos et al. (2006). For related literature and the synthetic procedure, see Martins et al. (2004, 2006). For the pharmacological activity, see Almanza et al. (2001); Novinson et al. (1977); George (2001).

Experimental top

To a stirred solution of 1,1,1-trifluoro-4-methoxy-4-(4-tolyl)-but-3-en-2-one (0.244 g, 1.0 mmol) in acetic acid (5 ml) a solution containing the 5-methyl-3-amino-1H-pyrazole (0.097 g, 1.0 mmol) in acetic acid (5 ml) was added dropwise. The mixture was stirred under reflux for 16 h. After this time, the resultant solution was extracted with chloroform (3 × 10 ml), washed with distilled water (3 × 10 ml) and dried over magnesium sulfate. Finally, the solvent was removed under reduced pressure and a solid was obtained in good yield (79%). The product was purified by recrystallization from hexane, the slow evaporation of this solution at room temperature furnished the crystal used for the data collection.

Refinement top

All H atoms were refined using a riding model, with C—H distances set to 0.93 or 0.96 Å. Uiso(H) = xUeq(C), with x = 1.5 for methyl groups and x = 1.2 otherwise.

Structure description top

Pyrazolopyrimidine derivatives are important biologically active compounds obtained to showed anti-inflammatory (PGHS-2 inhibitors) (Almanza et al., 2001) and antifungal activities (cAMP phosphodiasterase and xanthine oxidase inhibitors) (Novinson et al., 1977). In addition, this scaffold have been found to be integral parts of potent nonbenzodiazepine hypnotic agents (George, 2001). Zaleplon is one example of a pyrazolopyrimidine derivative in clinical use (George, 2001). In a continuation of our study about synthesis and reactivity of pyrazolopyrimidine (Martins et al., 2006) as well as trihalomethylated compounds (Martins et al., 2004) we reported, in this communication, the crystal structure of the title compound, 2-methyl-5-(4-tolyl)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine.

The analysis showed that the pyrazolo[1,5-a]pyrimidine ring is essentially planar with maximum deviation from mean plane of 0.014 (1) Å. The 4-tolyl group makes a dihedral angle of 14.1 (1)° with respect to the pyrazolo[1,5-a]pyrimidine ring system. In addition, the dihedral angle between the five-membered ring and the fused six-membered ring is 0.84 (1)° in accordance with previous reports (Wen et al., 2004; Wen et al., 2005; Oliveira-Campos et al., 2006). The crystal packing is stabilized mainly by van der Waals forces.

For related pyrazolopyrimidine compounds, see Wen et al. (2004, 2005); Oliveira-Campos et al. (2006). For related literature and the synthetic procedure, see Martins et al. (2004, 2006). For the pharmacological activity, see Almanza et al. (2001); Novinson et al. (1977); George (2001).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. View of the asymmetric unit of the title compound, showing the atom labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented by circles of arbitrary radii.
2-Methyl-5-(4-tolyl)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine top
Crystal data top
C15H12F3N3Z = 2
Mr = 291.28F(000) = 300
Triclinic, P1Dx = 1.433 Mg m−3
Hall symbol: -P 1Melting point = 415–416 K
a = 4.8715 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.2655 (5) ÅCell parameters from 150 reflections
c = 13.5584 (6) Åθ = 3.0–24.6°
α = 110.225 (3)°µ = 0.12 mm−1
β = 96.808 (3)°T = 293 K
γ = 99.835 (3)°Block, yellow
V = 675.13 (5) Å30.98 × 0.21 × 0.20 mm
Data collection top
X8 APEXII
diffractometer		2200 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.040
φ and ω scansθmax = 29.7°, θmin = 1.6°
Absorption correction: multi-scan
(XPREP; Bruker, 2006)		h = −6→6
Tmin = 0.874, Tmax = 0.977k = −15→15
16787 measured reflectionsl = −18→18
3757 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.227H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.1373P)2]
where P = (Fo2 + 2Fc2)/3
3757 reflections(Δ/σ)max < 0.001
190 parametersΔρmax = 0.40 e Å−3
0 restraintsΔρmin = −0.45 e Å−3
Crystal data top
C15H12F3N3γ = 99.835 (3)°
Mr = 291.28V = 675.13 (5) Å3
Triclinic, P1Z = 2
a = 4.8715 (2) ÅMo Kα radiation
b = 11.2655 (5) ŵ = 0.12 mm−1
c = 13.5584 (6) ÅT = 293 K
α = 110.225 (3)°0.98 × 0.21 × 0.20 mm
β = 96.808 (3)°
Data collection top
X8 APEXII
diffractometer		3757 independent reflections
Absorption correction: multi-scan
(XPREP; Bruker, 2006)		2200 reflections with I > 2σ(I)
Tmin = 0.874, Tmax = 0.977Rint = 0.040
16787 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0570 restraints
wR(F2) = 0.227H-atom parameters constrained
S = 1.05Δρmax = 0.40 e Å−3
3757 reflectionsΔρmin = −0.45 e Å−3
190 parameters
Special details top

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 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 > σ(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
N4−0.1395 (3)0.64063 (13)0.15766 (10)0.0437 (4)
C510.2301 (3)0.60519 (16)0.27094 (13)0.0434 (4)
C50.0595 (3)0.69036 (16)0.24463 (12)0.0427 (4)
N1A−0.2415 (3)0.85107 (14)0.19699 (11)0.0475 (4)
C3A−0.2918 (3)0.71919 (16)0.13244 (13)0.0443 (4)
C7−0.0385 (4)0.90322 (17)0.28737 (15)0.0517 (4)
N1−0.4126 (3)0.91420 (15)0.15720 (13)0.0560 (4)
C60.1130 (4)0.82475 (17)0.31325 (14)0.0501 (4)
H60.25140.85770.37530.06*
C560.2277 (4)0.48484 (18)0.19505 (14)0.0526 (5)
H560.11650.45750.12710.063*
C550.3880 (4)0.40510 (18)0.21898 (15)0.0571 (5)
H550.3810.32450.16680.069*
C520.4029 (4)0.64261 (19)0.37085 (15)0.0584 (5)
H520.40970.7230.42330.07*
C540.5592 (4)0.44182 (19)0.31862 (15)0.0539 (5)
C3−0.5081 (4)0.69986 (19)0.04969 (15)0.0514 (4)
H3−0.59390.622−0.00680.062*
C2−0.5725 (4)0.81980 (18)0.06756 (15)0.0522 (5)
C530.5645 (5)0.5626 (2)0.39352 (16)0.0631 (5)
H530.67960.59060.46080.076*
C80.7329 (5)0.3537 (2)0.34284 (18)0.0700 (6)
H8A0.70310.27540.28070.105*
H8B0.67630.33270.40140.105*
H8C0.93030.39670.36190.105*
C710.0064 (5)1.0448 (2)0.3532 (2)0.0714 (6)
C21−0.7881 (4)0.8562 (2)0.00171 (18)0.0689 (6)
H21A−0.78280.94710.03530.103*
H21B−0.97380.8064−0.00360.103*
H21C−0.74570.8385−0.06860.103*
F3−0.2264 (3)1.07474 (12)0.38784 (11)0.0893 (5)
F10.2076 (3)1.07989 (12)0.43939 (12)0.1008 (6)
F20.0852 (3)1.11914 (12)0.29935 (14)0.1004 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N40.0444 (8)0.0425 (8)0.0452 (7)0.0121 (6)0.0056 (6)0.0175 (6)
C510.0427 (9)0.0434 (9)0.0449 (9)0.0114 (7)0.0059 (6)0.0177 (7)
C50.0430 (9)0.0401 (9)0.0447 (9)0.0100 (6)0.0078 (6)0.0155 (7)
N1A0.0449 (8)0.0430 (8)0.0557 (8)0.0131 (6)0.0048 (6)0.0197 (7)
C3A0.0449 (9)0.0425 (9)0.0476 (9)0.0113 (7)0.0081 (7)0.0191 (7)
C70.0478 (10)0.0399 (9)0.0606 (11)0.0105 (7)0.0043 (8)0.0121 (8)
N10.0507 (9)0.0533 (10)0.0723 (10)0.0189 (7)0.0068 (7)0.0318 (8)
C60.0472 (10)0.0425 (9)0.0522 (10)0.0106 (7)−0.0016 (7)0.0109 (8)
C560.0583 (11)0.0473 (10)0.0510 (10)0.0183 (8)0.0021 (8)0.0168 (8)
C550.0628 (12)0.0511 (11)0.0613 (11)0.0257 (9)0.0107 (9)0.0201 (9)
C520.0654 (12)0.0500 (11)0.0530 (10)0.0179 (9)−0.0029 (9)0.0133 (8)
C540.0471 (10)0.0617 (12)0.0653 (11)0.0200 (8)0.0125 (8)0.0346 (9)
C30.0495 (10)0.0514 (10)0.0526 (9)0.0108 (7)0.0018 (7)0.0213 (8)
C20.0453 (9)0.0570 (11)0.0617 (11)0.0134 (8)0.0080 (8)0.0310 (9)
C530.0654 (12)0.0637 (13)0.0580 (11)0.0204 (9)−0.0065 (9)0.0233 (10)
C80.0662 (13)0.0779 (14)0.0844 (15)0.0355 (11)0.0151 (11)0.0438 (12)
C710.0619 (13)0.0448 (11)0.0919 (16)0.0169 (9)−0.0039 (11)0.0104 (11)
C210.0577 (12)0.0765 (15)0.0826 (14)0.0196 (10)0.0006 (10)0.0442 (12)
F30.0826 (10)0.0650 (9)0.1014 (10)0.0344 (7)0.0122 (8)0.0017 (7)
F10.0906 (11)0.0543 (8)0.1095 (11)0.0197 (7)−0.0302 (9)−0.0132 (7)
F20.0970 (11)0.0468 (8)0.1534 (14)0.0113 (7)0.0153 (10)0.0378 (8)
Geometric parameters (Å, º) top
N4—C51.316 (2)C52—C531.379 (3)
N4—C3A1.351 (2)C52—H520.93
C51—C561.387 (2)C54—C531.382 (3)
C51—C521.391 (2)C54—C81.502 (3)
C51—C51.475 (2)C3—C21.385 (3)
C5—C61.435 (2)C3—H30.93
N1A—C71.357 (2)C2—C211.499 (3)
N1A—N11.3609 (19)C53—H530.93
N1A—C3A1.400 (2)C8—H8A0.96
C3A—C31.375 (2)C8—H8B0.96
C7—C61.351 (2)C8—H8C0.96
C7—C711.496 (3)C71—F11.326 (2)
N1—C21.347 (2)C71—F21.328 (3)
C6—H60.93C71—F31.330 (3)
C56—C551.380 (2)C21—H21A0.96
C56—H560.93C21—H21B0.96
C55—C541.386 (3)C21—H21C0.96
C55—H550.93
C5—N4—C3A118.71 (14)C53—C54—C8121.90 (18)
C56—C51—C52117.46 (16)C55—C54—C8120.90 (18)
C56—C51—C5120.61 (15)C3A—C3—C2106.06 (16)
C52—C51—C5121.91 (15)C3A—C3—H3127
N4—C5—C6121.31 (15)C2—C3—H3127
N4—C5—C51118.72 (14)N1—C2—C3113.05 (16)
C6—C5—C51119.96 (15)N1—C2—C21117.78 (17)
C7—N1A—N1127.00 (15)C3—C2—C21129.17 (17)
C7—N1A—C3A120.58 (14)C52—C53—C54121.53 (17)
N1—N1A—C3A112.42 (14)C52—C53—H53119.2
N4—C3A—C3133.62 (16)C54—C53—H53119.2
N4—C3A—N1A121.23 (15)C54—C8—H8A109.5
C3—C3A—N1A105.15 (15)C54—C8—H8B109.5
C6—C7—N1A118.36 (16)H8A—C8—H8B109.5
C6—C7—C71123.34 (17)C54—C8—H8C109.5
N1A—C7—C71118.31 (16)H8A—C8—H8C109.5
C2—N1—N1A103.32 (14)H8B—C8—H8C109.5
C7—C6—C5119.78 (16)F1—C71—F2107.13 (18)
C7—C6—H6120.1F1—C71—F3106.74 (19)
C5—C6—H6120.1F2—C71—F3107.32 (18)
C55—C56—C51120.88 (17)F1—C71—C7110.86 (17)
C55—C56—H56119.6F2—C71—C7112.3 (2)
C51—C56—H56119.6F3—C71—C7112.17 (18)
C56—C55—C54121.77 (17)C2—C21—H21A109.5
C56—C55—H55119.1C2—C21—H21B109.5
C54—C55—H55119.1H21A—C21—H21B109.5
C53—C52—C51121.14 (17)C2—C21—H21C109.5
C53—C52—H52119.4H21A—C21—H21C109.5
C51—C52—H52119.4H21B—C21—H21C109.5
C53—C54—C55117.20 (17)
N4—C51—C5—C56−14.5 (3)N4—C51—C5—C52166.90 (16)

Experimental details

Crystal data
Chemical formulaC15H12F3N3
Mr291.28
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)4.8715 (2), 11.2655 (5), 13.5584 (6)
α, β, γ (°)110.225 (3), 96.808 (3), 99.835 (3)
V (Å3)675.13 (5)
Z2
Radiation typeMo Kα
µ (mm−1)0.12
Crystal size (mm)0.98 × 0.21 × 0.20
Data collection
DiffractometerX8 APEXII
Absorption correctionMulti-scan
(XPREP; Bruker, 2006)
Tmin, Tmax0.874, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections		16787, 3757, 2200
Rint0.040
(sin θ/λ)max (Å−1)0.696
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.227, 1.05
No. of reflections3757
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.40, −0.45

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997).

 

Acknowledgements

The authors thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq/PRONEX) and Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) for financial support. The fellowships from CNPq and CAPES are also acknowledged. The diffractometer was funded by a CT-INFRA grant from the Financiadora de Estudos e Projetos (FINEP), Brazil.

References

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ISSN: 2056-9890
Volume 64| Part 1| January 2008| Page o212
https://doi.org/10.1107/S1600536807064318
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