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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890

7-Chloro-5-(2-eth­oxy­phen­yl)-1-methyl-3-propyl-2,6-di­hydro-1H-pyrazolo[4,3-d]pyrimidine

aCollege of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technolgy, Xinmofan Road No. 5 Nanjing, Nanjing 210009, People's Republic of China
*Correspondence e-mail: hpf@njut.edu.cn

(Received 21 August 2009; accepted 25 August 2009; online 5 September 2009)

In the title compound, C17H21ClN4O, the benzene ring is oriented at dihedral angles of 1.59 (3) and 1.27 (3)° with respect to the pyrimidine and pyrazole rings, while the dihedral angle between the pyrimidine and pyrazole rings is 0.83 (3)°. An intra­molecular N—H⋯O hydrogen bond results in the formation of a planar (r.m.s. deviation 0.004 Å) six-membered ring.

Related literature

For a related structure, see: Rajesh & Joshi (2007[Rajesh, K. & Joshi, Y. C. (2007). Arkivoc, pp. 142-149.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C17H21ClN4O

  • Mr = 332.83

  • Triclinic, [P \overline 1]

  • a = 4.6700 (9) Å

  • b = 11.647 (2) Å

  • c = 16.064 (3) Å

  • α = 78.56 (3)°

  • β = 86.75 (3)°

  • γ = 79.81 (3)°

  • V = 842.7 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.24 mm−1

  • T = 294 K

  • 0.30 × 0.10 × 0.10 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.932, Tmax = 0.977

  • 3470 measured reflections

  • 3061 independent reflections

  • 2353 reflections with I > 2σ(I)

  • Rint = 0.033

  • 3 standard reflections frequency: 120 min intensity decay: 1%

Refinement
  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.182

  • S = 1.00

  • 3061 reflections

  • 208 parameters

  • H-atom parameters constrained

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.52 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O1 0.86 1.91 2.616 (3) 138

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97 and PLATON.

Supporting information


Comment top

Some derivatives of 5-(2-ethoxyphenyl)-1-methyl-3-propyl-1,6-dihydro-7H -pyrazolo[4,3-d]pyrimidin-7-one are important chemical materials. We report herein the crystal structure of the title compound.

In the molecule of the title compound, (Fig. 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Rings A (C3-C8), B (N1/N2/C9-C12) and C (N3/N4/C10/C11/C13) are, of course, planar. The dihedral angles between them are A/B = 1.59 (3), A/C = 1.27 (3) and B/C = 0.83 (3) °. The intramolecular N-H···O hydrogen bond (Table 1) results in the formation of a planar six-membered ring D (O1/N1/C3/C8/C9/H1A), which is oriented with respect to the other rings at dihedral angles of A/D = 1.01 (3), B/D = 0.63 (3) and C/D = 0.83 (3) °. So, the rings are almost coplanar.

Related literature top

For a related structure, see: Rajesh & Joshi (2007). For bond-length data, see: Allen et al. (1987).

Experimental top

For the preparation of the title compound, 5-(2-ethoxyphenyl)-1-methyl-3-propyl -1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (15.6 g) and phosphorus trichloride (13.7 g) were added into carbon tetrachloride (100 ml) at 345-350 K. The gross products were extracted with n-hexane, dried under vaccum, and then recrystallized in dichloromethane. Finally the title compound is obtained (yield; 1.5 g) (Rajesh et al., 2007). Crystals suitable for X-ray analysis were obtained by slow evaporation of a methanol solution.

Refinement top

H atoms were positioned geometrically with N-H = 0.86 Å (for NH) and C-H = 0.93, 0.97 and 0.96 Å for aromatic, methylene and methyl H atoms, respectively, and constrained to ride on their parent atoms with Uiso(H) = xUeq(C,N), where x = 1.5 for methyl H and x = 1.2 for all other H atoms.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); 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) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Hydrogen bond is shown as dashed line.
7-Chloro-5-(2-ethoxyphenyl)-1-methyl-3-propyl-2,6-dihydro- 1H-pyrazolo[4,3-d]pyrimidine top
Crystal data top
C17H21ClN4OZ = 2
Mr = 332.83F(000) = 352
Triclinic, P1Dx = 1.312 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 4.6700 (9) ÅCell parameters from 25 reflections
b = 11.647 (2) Åθ = 9–13°
c = 16.064 (3) ŵ = 0.24 mm1
α = 78.56 (3)°T = 294 K
β = 86.75 (3)°BlocK, yellow
γ = 79.81 (3)°0.30 × 0.10 × 0.10 mm
V = 842.7 (3) Å3
Data collection top
Enraf–Nonius CAD-4
diffractometer
2353 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.033
Graphite monochromatorθmax = 25.3°, θmin = 1.3°
ω/2θ scansh = 05
Absorption correction: ψ scan
(North et al., 1968)
k = 1313
Tmin = 0.932, Tmax = 0.977l = 1919
3470 measured reflections3 standard reflections every 120 min
3061 independent reflections intensity decay: 1%
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)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.182H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.1P)2 + 0.6P]
where P = (Fo2 + 2Fc2)/3
3061 reflections(Δ/σ)max = 0.001
208 parametersΔρmax = 0.38 e Å3
0 restraintsΔρmin = 0.52 e Å3
Crystal data top
C17H21ClN4Oγ = 79.81 (3)°
Mr = 332.83V = 842.7 (3) Å3
Triclinic, P1Z = 2
a = 4.6700 (9) ÅMo Kα radiation
b = 11.647 (2) ŵ = 0.24 mm1
c = 16.064 (3) ÅT = 294 K
α = 78.56 (3)°0.30 × 0.10 × 0.10 mm
β = 86.75 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
2353 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)
Rint = 0.033
Tmin = 0.932, Tmax = 0.9773 standard reflections every 120 min
3470 measured reflections intensity decay: 1%
3061 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0640 restraints
wR(F2) = 0.182H-atom parameters constrained
S = 1.00Δρmax = 0.38 e Å3
3061 reflectionsΔρmin = 0.52 e Å3
208 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
Cl0.45734 (19)0.18716 (7)0.56202 (5)0.0581 (3)
O10.4864 (5)0.49028 (18)0.68108 (14)0.0528 (6)
N10.6871 (5)0.2658 (2)0.68131 (14)0.0420 (6)
H1A0.57530.33130.66130.050*
N21.0314 (5)0.1732 (2)0.78486 (14)0.0414 (6)
N31.1345 (6)0.1091 (2)0.72458 (16)0.0506 (7)
H3A1.20750.18280.72690.061*
N40.9354 (6)0.0435 (2)0.66884 (16)0.0466 (6)
C10.1508 (7)0.5709 (3)0.5722 (2)0.0605 (9)
H1B0.02840.64160.54430.091*
H1C0.03350.51190.59560.091*
H1D0.28930.54100.53190.091*
C20.3079 (7)0.5992 (3)0.6417 (2)0.0550 (8)
H2B0.42780.65870.61890.066*
H2C0.17030.62970.68290.066*
C30.6554 (7)0.4882 (3)0.74759 (19)0.0452 (7)
C40.6545 (8)0.5877 (3)0.7839 (2)0.0597 (9)
H4A0.53250.65870.76320.072*
C50.8344 (9)0.5806 (3)0.8503 (2)0.0671 (10)
H5A0.83250.64700.87440.081*
C61.0161 (9)0.4770 (3)0.8812 (2)0.0635 (9)
H6A1.13840.47350.92570.076*
C71.0177 (7)0.3782 (3)0.8465 (2)0.0528 (8)
H7A1.14180.30820.86830.063*
C80.8384 (6)0.3800 (3)0.77958 (18)0.0428 (7)
C90.8566 (6)0.2674 (2)0.74811 (17)0.0393 (6)
C101.0325 (6)0.0743 (2)0.75138 (17)0.0397 (6)
C110.8671 (6)0.0690 (2)0.68347 (17)0.0398 (6)
C120.6759 (6)0.1717 (2)0.64296 (17)0.0389 (6)
C131.1973 (6)0.0409 (3)0.77464 (19)0.0443 (7)
C140.8296 (8)0.0978 (3)0.6049 (2)0.0606 (9)
H14A0.92140.17950.61160.091*
H14B0.87520.05620.54930.091*
H14C0.62260.09340.61160.091*
C151.3994 (7)0.0863 (3)0.84708 (19)0.0502 (8)
H15A1.49930.02320.85510.060*
H15B1.54490.15060.83320.060*
C161.2456 (9)0.1304 (5)0.9283 (2)0.0868 (14)
H16A1.09740.06610.94090.104*
H16B1.14710.19360.91970.104*
C171.4345 (10)0.1757 (5)1.0040 (2)0.0865 (13)
H17A1.31730.20211.05270.130*
H17B1.52830.11321.01470.130*
H17C1.57930.24100.99320.130*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl0.0624 (5)0.0586 (5)0.0533 (5)0.0064 (4)0.0254 (4)0.0076 (4)
O10.0595 (13)0.0387 (11)0.0578 (13)0.0041 (10)0.0213 (11)0.0087 (9)
N10.0438 (13)0.0384 (13)0.0421 (13)0.0020 (10)0.0136 (11)0.0050 (10)
N20.0417 (13)0.0432 (13)0.0385 (12)0.0065 (10)0.0090 (10)0.0040 (10)
N30.0554 (16)0.0390 (13)0.0539 (15)0.0040 (12)0.0135 (12)0.0079 (11)
N40.0530 (15)0.0395 (13)0.0472 (14)0.0013 (11)0.0119 (12)0.0106 (11)
C10.0518 (19)0.061 (2)0.063 (2)0.0071 (16)0.0128 (16)0.0078 (17)
C20.0521 (19)0.0433 (17)0.063 (2)0.0070 (14)0.0095 (16)0.0055 (15)
C30.0453 (16)0.0440 (16)0.0469 (17)0.0074 (13)0.0020 (13)0.0102 (13)
C40.065 (2)0.0452 (18)0.070 (2)0.0044 (16)0.0089 (18)0.0163 (16)
C50.081 (3)0.057 (2)0.072 (2)0.0113 (19)0.012 (2)0.0298 (18)
C60.074 (2)0.065 (2)0.057 (2)0.0163 (19)0.0199 (18)0.0194 (17)
C70.0583 (19)0.0499 (18)0.0516 (18)0.0076 (15)0.0168 (15)0.0102 (14)
C80.0430 (16)0.0428 (16)0.0432 (15)0.0088 (13)0.0052 (13)0.0068 (12)
C90.0376 (14)0.0407 (15)0.0383 (14)0.0069 (12)0.0037 (12)0.0037 (12)
C100.0399 (15)0.0404 (15)0.0374 (14)0.0049 (12)0.0043 (12)0.0044 (12)
C110.0409 (15)0.0400 (15)0.0379 (14)0.0066 (12)0.0045 (12)0.0048 (12)
C120.0376 (14)0.0413 (15)0.0377 (14)0.0097 (12)0.0031 (12)0.0040 (12)
C130.0419 (16)0.0431 (16)0.0441 (16)0.0004 (12)0.0055 (13)0.0042 (13)
C140.074 (2)0.0503 (19)0.061 (2)0.0034 (17)0.0181 (18)0.0203 (16)
C150.0476 (17)0.0463 (17)0.0524 (18)0.0036 (13)0.0128 (14)0.0060 (14)
C160.060 (2)0.135 (4)0.057 (2)0.028 (2)0.0162 (19)0.014 (2)
C170.081 (3)0.117 (4)0.055 (2)0.024 (3)0.015 (2)0.010 (2)
Geometric parameters (Å, º) top
Cl—C121.660 (3)C5—C61.367 (5)
O1—C21.439 (4)C5—H5A0.9300
O1—C31.358 (4)C6—C71.373 (5)
N1—C91.374 (3)C6—H6A0.9300
N1—C121.369 (4)C7—C81.395 (4)
N1—H1A0.8600C7—H7A0.9300
N2—C91.304 (4)C8—C91.484 (4)
N2—C101.363 (4)C10—C111.389 (4)
N3—N41.350 (3)C10—C131.414 (4)
N3—C131.315 (4)C11—C121.425 (4)
N3—H3A0.8600C13—C151.493 (4)
N4—C111.356 (4)C14—H14A0.9600
N4—C141.458 (4)C14—H14B0.9600
C1—C21.489 (5)C14—H14C0.9600
C1—H1B0.9600C15—C161.497 (5)
C1—H1C0.9600C15—H15A0.9700
C1—H1D0.9600C15—H15B0.9700
C2—H2B0.9700C16—C171.496 (5)
C2—H2C0.9700C16—H16A0.9700
C3—C41.396 (4)C16—H16B0.9700
C3—C81.412 (4)C17—H17A0.9600
C4—C51.375 (5)C17—H17B0.9600
C4—H4A0.9300C17—H17C0.9600
C3—O1—C2120.4 (2)C3—C8—C9125.6 (3)
C12—N1—C9127.4 (2)N2—C9—N1122.1 (3)
C12—N1—H1A116.3N2—C9—C8119.1 (3)
C9—N1—H1A116.3N1—C9—C8118.8 (2)
C9—N2—C10114.6 (2)N2—C10—C11125.1 (3)
C13—N3—N4108.1 (2)N2—C10—C13129.4 (3)
C13—N3—H3A125.9C11—C10—C13105.4 (3)
N4—N3—H3A125.9N4—C11—C10106.8 (2)
N3—N4—C11110.3 (2)N4—C11—C12132.7 (3)
N3—N4—C14119.5 (2)C10—C11—C12120.5 (3)
C11—N4—C14130.2 (3)N1—C12—C11110.1 (2)
C2—C1—H1B109.5N1—C12—Cl120.5 (2)
C2—C1—H1C109.5C11—C12—Cl129.4 (2)
H1B—C1—H1C109.5N3—C13—C10109.3 (3)
C2—C1—H1D109.5N3—C13—C15122.6 (3)
H1B—C1—H1D109.5C10—C13—C15127.9 (3)
H1C—C1—H1D109.5N4—C14—H14A109.5
O1—C2—C1106.9 (3)N4—C14—H14B109.5
O1—C2—H2B110.3H14A—C14—H14B109.5
C1—C2—H2B110.3N4—C14—H14C109.5
O1—C2—H2C110.3H14A—C14—H14C109.5
C1—C2—H2C110.3H14B—C14—H14C109.5
H2B—C2—H2C108.6C13—C15—C16112.7 (3)
O1—C3—C4122.6 (3)C13—C15—H15A109.1
O1—C3—C8117.3 (3)C16—C15—H15A109.1
C4—C3—C8120.1 (3)C13—C15—H15B109.1
C5—C4—C3119.9 (3)C16—C15—H15B109.1
C5—C4—H4A120.0H15A—C15—H15B107.8
C3—C4—H4A120.0C17—C16—C15115.6 (3)
C6—C5—C4120.8 (3)C17—C16—H16A108.4
C6—C5—H5A119.6C15—C16—H16A108.4
C4—C5—H5A119.6C17—C16—H16B108.4
C5—C6—C7119.9 (3)C15—C16—H16B108.4
C5—C6—H6A120.1H16A—C16—H16B107.5
C7—C6—H6A120.1C16—C17—H17A109.5
C6—C7—C8121.8 (3)C16—C17—H17B109.5
C6—C7—H7A119.1H17A—C17—H17B109.5
C8—C7—H7A119.1C16—C17—H17C109.5
C7—C8—C3117.5 (3)H17A—C17—H17C109.5
C7—C8—C9116.9 (3)H17B—C17—H17C109.5
C3—O1—C2—C1179.6 (3)C6—C7—C8—C9179.3 (3)
C2—O1—C3—C43.4 (5)O1—C3—C8—C7178.4 (3)
C2—O1—C3—C8176.2 (3)C4—C3—C8—C71.2 (5)
C12—N1—C9—N21.2 (5)O1—C3—C8—C91.6 (5)
C12—N1—C9—C8179.2 (3)C4—C3—C8—C9178.8 (3)
C9—N1—C12—C111.1 (4)C7—C8—C9—N21.4 (4)
C9—N1—C12—Cl179.6 (2)C3—C8—C9—N2178.6 (3)
C10—N2—C9—N10.4 (4)C7—C8—C9—N1179.0 (3)
C10—N2—C9—C8180.0 (2)C3—C8—C9—N11.1 (4)
C9—N2—C10—C110.3 (4)N2—C10—C11—N4178.7 (3)
C9—N2—C10—C13178.9 (3)C13—C10—C11—N40.2 (3)
C13—N3—N4—C110.4 (3)N2—C10—C11—C120.3 (4)
C13—N3—N4—C14179.3 (3)C13—C10—C11—C12179.1 (3)
N4—N3—C13—C100.2 (3)N4—C11—C12—N1179.1 (3)
N4—N3—C13—C15176.7 (3)C10—C11—C12—N10.4 (4)
N3—N4—C11—C100.3 (3)N4—C11—C12—Cl1.7 (5)
C14—N4—C11—C10179.3 (3)C10—C11—C12—Cl179.6 (2)
N3—N4—C11—C12179.1 (3)N2—C10—C13—N3178.9 (3)
C14—N4—C11—C120.5 (6)C11—C10—C13—N30.1 (3)
O1—C3—C4—C5178.9 (3)N2—C10—C13—C154.9 (5)
C8—C3—C4—C50.7 (5)C11—C10—C13—C15176.3 (3)
C3—C4—C5—C60.3 (6)N3—C13—C15—C1690.3 (4)
C4—C5—C6—C70.7 (6)C10—C13—C15—C1685.5 (4)
C5—C6—C7—C80.2 (6)C13—C15—C16—C17179.2 (4)
C6—C7—C8—C30.7 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.861.912.616 (3)138

Experimental details

Crystal data
Chemical formulaC17H21ClN4O
Mr332.83
Crystal system, space groupTriclinic, P1
Temperature (K)294
a, b, c (Å)4.6700 (9), 11.647 (2), 16.064 (3)
α, β, γ (°)78.56 (3), 86.75 (3), 79.81 (3)
V3)842.7 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.24
Crystal size (mm)0.30 × 0.10 × 0.10
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionψ scan
(North et al., 1968)
Tmin, Tmax0.932, 0.977
No. of measured, independent and
observed [I > 2σ(I)] reflections
3470, 3061, 2353
Rint0.033
(sin θ/λ)max1)0.601
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.182, 1.00
No. of reflections3061
No. of parameters208
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.38, 0.52

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O10.861.912.616 (3)138.00
 

Acknowledgements

The authors thank the Innovation Fund for Doctoral Theses (BSCX200811) and Nanjing University of Technology for support.

References

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