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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Ethyl 6-methyl-2-p-tolyl­pyrazolo[1,5-a]pyridine-5-carboxyl­ate

aSchool of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
*Correspondence e-mail: yugp2005@yahoo.com.cn

(Received 29 August 2009; accepted 1 September 2009; online 9 September 2009)

In the title mol­ecule, C18H18N2O2, the bicyclic ring system and the benzene ring form a dihedral angle of 13.45 (3)°. In the crystal structure, weak inter­molecular C—H⋯O hydrogen bonds link mol­ecules into chains propagated along [201].

Related literature

For novel pyrazolo[1,5-a]pyridine compounds, see: Ge et al. (2009[Ge, Y. Q., Jia, J., Li, Y., Yin, L. & Wang, J. W. (2009). Heterocycles, 78, 197-206.]). For a related structure, see: Shao et al. (2009[Shao, T., Zhao, G. & Wang, J. (2009). Acta Cryst. E65, o923.]).

[Scheme 1]

Experimental

Crystal data
  • C18H18N2O2

  • Mr = 294.34

  • Monoclinic, P 21 /c

  • a = 6.8352 (3) Å

  • b = 30.3999 (11) Å

  • c = 7.5409 (3) Å

  • β = 97.375 (2)°

  • V = 1553.96 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 293 K

  • 0.43 × 0.32 × 0.21 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.965, Tmax = 0.983

  • 18651 measured reflections

  • 3181 independent reflections

  • 2166 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.056

  • wR(F2) = 0.148

  • S = 1.07

  • 3181 reflections

  • 199 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C9—H9A⋯O3i 0.93 2.42 3.339 (3) 170
Symmetry code: (i) [x+1, -y+{\script{3\over 2}}, z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The pyrazolo[1,5-a]pyridine derivatives have been of interest for their pharmacological and biological activities. Considerable efforts of our group have been devoted to the development of novel pyrazolo[1,5-a]pyridine compounds(Ge et al., 2009). In continuation of this work, we report here the crystal structure of the title compound, (I) (Fig. 1).

In (I), all bond lengths are normal and in a good agreement with those reported previously (Shao et al., 2009). Atoms O2/O3/C15/C16/C17/C18 lie in 1H-pyrazolo[1,5-a]pyridine (C8—C14/N1/N2) plane with the maximum deviation of 0.065 (3) Å for O2. The 1H-pyrazolo[1,5-a]pyridine plane forms dihedral angle of 13.45 (3)° with the benzene ring (C2—C7).

In the crystal structure, weak intermolecular C–H···O hydrogen bond (Table 1) link the molecules into chains propagated in direction [201].

Related literature top

For novel pyrazolo[1,5-a]pyridine compounds, see: Ge et al. (2009). For arelated structure, see: Shao et al. (2009).

Experimental top

To a 50-ml round-bottomed flask were added 3-p-tolyl-1H-pyrazole-5-carbaldehyde(6.0 mmol), ethyl 4-bromo-3-methylbut-2-enoate (7.2 mmol), potassium carbonate (1.60 g, 12.5 mmol) and DMF (10 mL). The mixture was stirred at rt for 8 h and then filtered. The filtrate was poured into water (100 ml) and extracted with CH2Cl2 (3 x 30 ml). The combined extracts were washed with water (2 x 50 ml), dried over anhydrous MgSO4 and filtered, and the solvent was removed by rotary evaporation. The crude product was purified by column chromatography (yield 75%). Crystals of (I) suitable for X-ray diffraction were obtained by slow cooling of the refluxed solution of the product in ethyl acetate at room temperature for 2 d.

Refinement top

All H atoms were placed in calculated positions [C–H = 0.93–0.97 Å], and included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(C) for the methyl H atoms.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of the title compound, with displacement ellipsoids drawn at the 40% probability level.
Ethyl 6-methyl-2-p-tolylpyrazolo[1,5-a]pyridine-5-carboxylate top
Crystal data top
C18H18N2O2F(000) = 624
Mr = 294.34Dx = 1.258 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4574 reflections
a = 6.8352 (3) Åθ = 2.7–24.2°
b = 30.3999 (11) ŵ = 0.08 mm1
c = 7.5409 (3) ÅT = 293 K
β = 97.375 (2)°Block, colourless
V = 1553.96 (11) Å30.43 × 0.32 × 0.21 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer
3181 independent reflections
Radiation source: fine-focus sealed tube2166 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
ϕ and ω scansθmax = 26.3°, θmin = 1.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 88
Tmin = 0.965, Tmax = 0.983k = 3737
18651 measured reflectionsl = 99
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)] = 0.056Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.148H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0589P)2 + 0.5452P]
where P = (Fo2 + 2Fc2)/3
3181 reflections(Δ/σ)max < 0.001
199 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C18H18N2O2V = 1553.96 (11) Å3
Mr = 294.34Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.8352 (3) ŵ = 0.08 mm1
b = 30.3999 (11) ÅT = 293 K
c = 7.5409 (3) Å0.43 × 0.32 × 0.21 mm
β = 97.375 (2)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
3181 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2166 reflections with I > 2σ(I)
Tmin = 0.965, Tmax = 0.983Rint = 0.036
18651 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0560 restraints
wR(F2) = 0.148H-atom parameters constrained
S = 1.07Δρmax = 0.23 e Å3
3181 reflectionsΔρmin = 0.22 e Å3
199 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
N10.3372 (2)0.65607 (5)0.5370 (2)0.0429 (4)
N20.3988 (2)0.61395 (6)0.5589 (2)0.0482 (4)
O20.3651 (2)0.81645 (4)0.5569 (2)0.0561 (4)
O30.0666 (3)0.80858 (6)0.4073 (3)0.0806 (6)
C11.0771 (5)0.46224 (8)0.7690 (4)0.0820 (8)
H1A1.21230.47110.79750.123*
H1B1.06270.44500.66150.123*
H1C1.03860.44500.86540.123*
C20.9475 (4)0.50258 (8)0.7418 (3)0.0589 (6)
C31.0264 (4)0.54415 (8)0.7553 (3)0.0638 (6)
H3A1.16190.54740.78520.077*
C40.9101 (3)0.58130 (7)0.7255 (3)0.0563 (6)
H4A0.96830.60900.73660.068*
C50.7080 (3)0.57786 (6)0.6794 (3)0.0460 (5)
C60.6282 (4)0.53587 (7)0.6683 (3)0.0636 (6)
H6A0.49270.53240.63920.076*
C70.7463 (4)0.49920 (8)0.6995 (4)0.0695 (7)
H7A0.68850.47150.69180.083*
C80.5871 (3)0.61754 (6)0.6386 (3)0.0435 (5)
C90.6428 (3)0.66109 (7)0.6684 (3)0.0464 (5)
H9A0.76430.67140.72210.056*
C100.4813 (3)0.68603 (6)0.6023 (3)0.0423 (5)
C110.4335 (3)0.73089 (6)0.5842 (3)0.0440 (5)
H11A0.52600.75190.62880.053*
C120.2535 (3)0.74423 (7)0.5024 (2)0.0412 (5)
C130.1075 (3)0.71204 (7)0.4353 (3)0.0441 (5)
C140.1553 (3)0.66890 (7)0.4564 (3)0.0473 (5)
H14A0.06280.64760.41530.057*
C150.0942 (3)0.72349 (8)0.3412 (3)0.0557 (6)
H15A0.16600.69700.30830.084*
H15B0.08070.74030.23570.084*
H15C0.16440.74050.41970.084*
C160.2140 (3)0.79236 (7)0.4827 (3)0.0476 (5)
C170.3473 (4)0.86376 (7)0.5387 (3)0.0624 (6)
H17A0.24080.87440.60070.075*
H17B0.31900.87180.41350.075*
C180.5387 (4)0.88348 (8)0.6182 (3)0.0757 (8)
H18A0.53130.91490.60780.114*
H18B0.64290.87270.55570.114*
H18C0.56490.87550.74210.114*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0375 (9)0.0432 (10)0.0472 (9)0.0043 (7)0.0016 (7)0.0009 (7)
N20.0473 (10)0.0404 (10)0.0560 (10)0.0027 (8)0.0035 (8)0.0002 (8)
O20.0546 (9)0.0407 (9)0.0710 (10)0.0009 (7)0.0008 (7)0.0056 (7)
O30.0562 (10)0.0558 (11)0.1210 (15)0.0076 (8)0.0225 (10)0.0140 (10)
C10.101 (2)0.0602 (17)0.0863 (19)0.0314 (15)0.0167 (16)0.0084 (14)
C20.0711 (17)0.0490 (14)0.0574 (13)0.0134 (12)0.0116 (11)0.0033 (10)
C30.0520 (14)0.0598 (16)0.0790 (17)0.0093 (12)0.0058 (12)0.0061 (12)
C40.0516 (13)0.0448 (13)0.0719 (15)0.0004 (10)0.0062 (11)0.0037 (11)
C50.0476 (12)0.0423 (12)0.0487 (11)0.0007 (9)0.0078 (9)0.0003 (9)
C60.0553 (14)0.0488 (14)0.0850 (17)0.0039 (11)0.0027 (12)0.0019 (12)
C70.0785 (18)0.0384 (13)0.0909 (19)0.0012 (12)0.0081 (14)0.0013 (12)
C80.0414 (11)0.0436 (12)0.0454 (11)0.0024 (9)0.0050 (9)0.0006 (9)
C90.0388 (11)0.0441 (12)0.0547 (12)0.0031 (9)0.0007 (9)0.0001 (9)
C100.0372 (10)0.0432 (12)0.0455 (11)0.0049 (9)0.0022 (8)0.0004 (8)
C110.0405 (11)0.0407 (11)0.0500 (11)0.0051 (9)0.0022 (9)0.0001 (9)
C120.0374 (10)0.0451 (12)0.0411 (10)0.0001 (9)0.0045 (8)0.0038 (8)
C130.0361 (10)0.0534 (13)0.0425 (11)0.0011 (9)0.0036 (8)0.0030 (9)
C140.0367 (11)0.0533 (13)0.0502 (12)0.0071 (9)0.0008 (9)0.0013 (9)
C150.0408 (12)0.0626 (14)0.0609 (14)0.0007 (10)0.0042 (10)0.0036 (11)
C160.0406 (11)0.0510 (13)0.0512 (12)0.0006 (10)0.0055 (9)0.0055 (10)
C170.0741 (17)0.0418 (13)0.0731 (16)0.0030 (12)0.0157 (13)0.0056 (11)
C180.094 (2)0.0588 (16)0.0740 (17)0.0194 (14)0.0101 (15)0.0054 (13)
Geometric parameters (Å, º) top
N1—N21.351 (2)C7—H7A0.9300
N1—C141.369 (2)C8—C91.388 (3)
N1—C101.385 (2)C9—C101.379 (3)
N2—C81.353 (2)C9—H9A0.9300
O2—C161.330 (2)C10—C111.405 (3)
O2—C171.448 (3)C11—C121.365 (3)
O3—C161.198 (2)C11—H11A0.9300
C1—C21.511 (3)C12—C131.442 (3)
C1—H1A0.9600C12—C161.492 (3)
C1—H1B0.9600C13—C141.356 (3)
C1—H1C0.9600C13—C151.508 (3)
C2—C31.373 (3)C14—H14A0.9300
C2—C71.375 (4)C15—H15A0.9600
C3—C41.383 (3)C15—H15B0.9600
C3—H3A0.9300C15—H15C0.9600
C4—C51.384 (3)C17—C181.493 (3)
C4—H4A0.9300C17—H17A0.9700
C5—C61.386 (3)C17—H17B0.9700
C5—C81.472 (3)C18—H18A0.9600
C6—C71.379 (3)C18—H18B0.9600
C6—H6A0.9300C18—H18C0.9600
N2—N1—C14125.13 (17)C9—C10—C11137.25 (19)
N2—N1—C10112.56 (16)N1—C10—C11117.27 (17)
C14—N1—C10122.30 (17)C12—C11—C10121.13 (18)
N1—N2—C8103.98 (15)C12—C11—H11A119.4
C16—O2—C17117.10 (17)C10—C11—H11A119.4
C2—C1—H1A109.5C11—C12—C13120.00 (19)
C2—C1—H1B109.5C11—C12—C16118.51 (18)
H1A—C1—H1B109.5C13—C12—C16121.49 (17)
C2—C1—H1C109.5C14—C13—C12117.99 (18)
H1A—C1—H1C109.5C14—C13—C15118.08 (18)
H1B—C1—H1C109.5C12—C13—C15123.93 (19)
C3—C2—C7117.3 (2)C13—C14—N1121.30 (19)
C3—C2—C1121.3 (2)C13—C14—H14A119.3
C7—C2—C1121.5 (2)N1—C14—H14A119.3
C2—C3—C4121.8 (2)C13—C15—H15A109.5
C2—C3—H3A119.1C13—C15—H15B109.5
C4—C3—H3A119.1H15A—C15—H15B109.5
C3—C4—C5120.9 (2)C13—C15—H15C109.5
C3—C4—H4A119.6H15A—C15—H15C109.5
C5—C4—H4A119.6H15B—C15—H15C109.5
C4—C5—C6117.2 (2)O3—C16—O2122.3 (2)
C4—C5—C8120.38 (19)O3—C16—C12125.6 (2)
C6—C5—C8122.4 (2)O2—C16—C12112.17 (17)
C7—C6—C5121.1 (2)O2—C17—C18107.6 (2)
C7—C6—H6A119.4O2—C17—H17A110.2
C5—C6—H6A119.4C18—C17—H17A110.2
C2—C7—C6121.7 (2)O2—C17—H17B110.2
C2—C7—H7A119.2C18—C17—H17B110.2
C6—C7—H7A119.2H17A—C17—H17B108.5
N2—C8—C9111.98 (17)C17—C18—H18A109.5
N2—C8—C5120.22 (18)C17—C18—H18B109.5
C9—C8—C5127.78 (18)H18A—C18—H18B109.5
C10—C9—C8106.01 (17)C17—C18—H18C109.5
C10—C9—H9A127.0H18A—C18—H18C109.5
C8—C9—H9A127.0H18B—C18—H18C109.5
C9—C10—N1105.47 (17)
C14—N1—N2—C8178.09 (17)C14—N1—C10—C9178.47 (17)
C10—N1—N2—C80.5 (2)N2—N1—C10—C11179.20 (16)
C7—C2—C3—C40.8 (4)C14—N1—C10—C110.5 (3)
C1—C2—C3—C4178.1 (2)C9—C10—C11—C12177.3 (2)
C2—C3—C4—C50.5 (4)N1—C10—C11—C121.3 (3)
C3—C4—C5—C61.3 (3)C10—C11—C12—C131.0 (3)
C3—C4—C5—C8176.7 (2)C10—C11—C12—C16178.23 (18)
C4—C5—C6—C70.9 (4)C11—C12—C13—C140.0 (3)
C8—C5—C6—C7177.0 (2)C16—C12—C13—C14179.22 (18)
C3—C2—C7—C61.2 (4)C11—C12—C13—C15179.27 (19)
C1—C2—C7—C6177.6 (2)C16—C12—C13—C150.1 (3)
C5—C6—C7—C20.4 (4)C12—C13—C14—N10.7 (3)
N1—N2—C8—C90.7 (2)C15—C13—C14—N1178.58 (18)
N1—N2—C8—C5178.00 (17)N2—N1—C14—C13178.02 (18)
C4—C5—C8—N2166.40 (19)C10—N1—C14—C130.5 (3)
C6—C5—C8—N211.4 (3)C17—O2—C16—O31.8 (3)
C4—C5—C8—C912.0 (3)C17—O2—C16—C12177.15 (17)
C6—C5—C8—C9170.1 (2)C11—C12—C16—O3176.6 (2)
N2—C8—C9—C100.6 (2)C13—C12—C16—O32.6 (3)
C5—C8—C9—C10177.97 (19)C11—C12—C16—O22.3 (3)
C8—C9—C10—N10.2 (2)C13—C12—C16—O2178.51 (17)
C8—C9—C10—C11178.5 (2)C16—O2—C17—C18175.41 (18)
N2—N1—C10—C90.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9A···O3i0.932.423.339 (3)170
Symmetry code: (i) x+1, y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC18H18N2O2
Mr294.34
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)6.8352 (3), 30.3999 (11), 7.5409 (3)
β (°) 97.375 (2)
V3)1553.96 (11)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.43 × 0.32 × 0.21
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.965, 0.983
No. of measured, independent and
observed [I > 2σ(I)] reflections
18651, 3181, 2166
Rint0.036
(sin θ/λ)max1)0.624
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.056, 0.148, 1.07
No. of reflections3181
No. of parameters199
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.23, 0.22

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1999), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C9—H9A···O3i0.932.423.339 (3)170.0
Symmetry code: (i) x+1, y+3/2, z+1/2.
 

References

First citationBruker (1998). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationGe, Y. Q., Jia, J., Li, Y., Yin, L. & Wang, J. W. (2009). Heterocycles, 78, 197–206.  CAS Google Scholar
First citationShao, T., Zhao, G. & Wang, J. (2009). Acta Cryst. E65, o923.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds