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

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ISSN: 2056-9890

3-Oxo-5-(piperidin-1-yl)-2,3-di­hydro-1H-pyrazole-4-carbo­nitrile

aSchool of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Selangor, Malaysia, and bDepartment of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
*Correspondence e-mail: mbkassim@ukm.my

(Received 13 October 2011; accepted 10 November 2011; online 16 November 2011)

In the title compound, C9H12N4O, the piperidine ring adopts a chair conformation and makes a dihedral angle of 42.49 (11)° with the approximately planar pyrazole moiety [maximum deviation = 0.038 (2) Å]. In the crystal, N—H⋯O and N—H⋯N hydrogen bonds and a weak C—H⋯O inter­action link the mol­ecules into sheets lying parallel to (110).

Related literature

For pharmacological background, see: Patel et al. (1990[Patel, H. V., Fernandes, P. S. & Vyas, K. A. (1990). Indian J. Chem. Sect. B, 29, 135-141.]); Morimoto et al. (1990[Morimoto, K., Makino, K., Yamamoto, S. & Sakata, G. (1990). J. Heterocycl. Chem. 27, 807-810.]). For related structures see: Zaharan et al. (2001[Zaharan, M. A., El-Sharief, A. M. S., El-Gaby, M. S. A., Ammar, Y. A. & El-Said, U. H. (2001). Farmaco, 56, 277-283.]); Elgemeie et al. (2007[Elgemeie, G. H., Elghandour, A. H. & Abd Elaziz, G. W. (2007). Synth. Commun. 37, 2827-2834.]); Gouda et al. (2010[Gouda, M. A., Berghot, M. A., Abd El-Ghani, G. E. & Khalil, A. M. (2010). Eur. J. Med. Chem. 45, 1338-1345.]); Shelton et al. (2011[Shelton, A. H., Stephenson, A., Ward, M. D. & Kassim, M. B. (2011). Acta Cryst. E67, o2445.]). For standard bond lengths, 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
  • C9H12N4O

  • Mr = 192.23

  • Triclinic, [P \overline 1]

  • a = 7.2667 (5) Å

  • b = 7.9624 (5) Å

  • c = 8.8306 (8) Å

  • α = 89.280 (6)°

  • β = 75.934 (7)°

  • γ = 71.906 (6)°

  • V = 470.01 (6) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 0.77 mm−1

  • T = 150 K

  • 0.22 × 0.19 × 0.13 mm

Data collection
  • Oxford Diffraction Gemini diffractometer

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006[Oxford Diffraction (2006). Gemini User Manual. Oxford Diffraction Ltd, Abingdon, England.]) Tmin = 0.849, Tmax = 0.906

  • 5083 measured reflections

  • 1803 independent reflections

  • 1627 reflections with I > 2σ(I)

  • Rint = 0.013

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.166

  • S = 1.11

  • 1803 reflections

  • 127 parameters

  • H-atom parameters constrained

  • Δρmax = 0.74 e Å−3

  • Δρmin = −0.61 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯N4i 0.86 2.32 2.875 (3) 123
N3—H3⋯O1ii 0.86 2.07 2.772 (2) 138
C4—H4A⋯O1iii 0.97 2.54 3.258 (3) 131
Symmetry codes: (i) x-1, y, z; (ii) -x+2, -y, -z+1; (iii) x-1, y+1, z.

Data collection: Gemini User Manual (Oxford Diffraction, 2006[Oxford Diffraction (2006). Gemini User Manual. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2002[Oxford Diffraction (2002). CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]); data reduction: CrysAlis RED; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]), PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

In this paper, we report the synthesis and structure of the new derivative of 3-oxo-5-(piperidin-1-yl)-2,3-dihydro-1H- pyrazole-4-carbonitrile. The compound was obtained by cyclization reaction between ethyl 2-cyano-3-(methylthio)-3-(piperidin-1-yl)acrylate and hydrazine.

In the title compound (I), the mean plane of the pyrazole O1/N1/N2/N4/C5/C6/C7/C8/C9 is essentially planar with maximum deviation of -0.038 (2)° for C8 and forms a dihedral angle of 42.49 (11)° with that of the piperidine mean plane N1/C1/C2/C3/C4/C5 (Fig. 1 & Scheme 1). Consequently, a short non-bonding intra D—H..H—X contact forms between the N2—H2 of the pyrazole and the H5B—C5 of the piperidine moeities.

The carbonyl C8=O1 [1.246 (2)] and C6=C7 [1.407 (3) Å] are longer than the average [C=O(1.200 Å)] and C=C [(1.340 Å)] bond lengths, respectively. Whereas the C6—N2 [1.363 (2) Å] and C8—N3 [1.375 (2) Å] bond lengths are shorter than the average C—N [(1.47 Å)] indicative of electron-donating effects of the amino groups. Other bond lengths and angle in the molecules are in the normal ranges (Allen et al.,1987).

In the crystal, intermolecular hydrogen bonds N2—H2···O4 and N3—H3···O1 and a weak C4—H4···O1 interaction link the molecules forming a two-dimensional polymeric network parallel to (110) (Fig. 2).

Related literature top

For pharmacological background, see: Patel et al. (1990); Morimoto et al. (1990). For related structures see: Zaharan et al. (2001); Elgemeie et al. (2007); Gouda et al. (2010; Shelton et al. (2011). For standard bond lengths, see: Allen et al. (1987).

Experimental top

A mixture of ethyl 2-cyano-3-(methylthio)-3-(piperidin-1-yl)acrylate (4 mmol) and hydrazine hydrate (4 mmol) was heated on a water-bath for 2 h. Then, ethanol (20 ml) was added and the mixture was refluxed for another 2 h. The solvent was evaporated and the product was collected, washed with ethanol, and dried. Colourless blocks of (I) were formed by slow evaporation of the compound from ethanol solution. Yield = 90%.

Refinement top

H atoms of both C and N atoms were positioned geometrically and allowed to ride on their parent atoms, with Uiso = 1.2Ueq (C) for CH2 0.97 Å. Hydrogen atoms attached to N were also positioned geometrically and allowed to ride on their parent atoms and with Uiso(H) = 1.2Ueq(N) for N–H 0.86 Å.

Structure description top

In this paper, we report the synthesis and structure of the new derivative of 3-oxo-5-(piperidin-1-yl)-2,3-dihydro-1H- pyrazole-4-carbonitrile. The compound was obtained by cyclization reaction between ethyl 2-cyano-3-(methylthio)-3-(piperidin-1-yl)acrylate and hydrazine.

In the title compound (I), the mean plane of the pyrazole O1/N1/N2/N4/C5/C6/C7/C8/C9 is essentially planar with maximum deviation of -0.038 (2)° for C8 and forms a dihedral angle of 42.49 (11)° with that of the piperidine mean plane N1/C1/C2/C3/C4/C5 (Fig. 1 & Scheme 1). Consequently, a short non-bonding intra D—H..H—X contact forms between the N2—H2 of the pyrazole and the H5B—C5 of the piperidine moeities.

The carbonyl C8=O1 [1.246 (2)] and C6=C7 [1.407 (3) Å] are longer than the average [C=O(1.200 Å)] and C=C [(1.340 Å)] bond lengths, respectively. Whereas the C6—N2 [1.363 (2) Å] and C8—N3 [1.375 (2) Å] bond lengths are shorter than the average C—N [(1.47 Å)] indicative of electron-donating effects of the amino groups. Other bond lengths and angle in the molecules are in the normal ranges (Allen et al.,1987).

In the crystal, intermolecular hydrogen bonds N2—H2···O4 and N3—H3···O1 and a weak C4—H4···O1 interaction link the molecules forming a two-dimensional polymeric network parallel to (110) (Fig. 2).

For pharmacological background, see: Patel et al. (1990); Morimoto et al. (1990). For related structures see: Zaharan et al. (2001); Elgemeie et al. (2007); Gouda et al. (2010; Shelton et al. (2011). For standard bond lengths, see: Allen et al. (1987).

Computing details top

Data collection: Gemini User Manual (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2002); data reduction: CrysAlis RED (Oxford Diffraction, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. Crystal packing of (I) viewed down the a axis. Hydrogen bonds [N—H···O (x-1, y, z & -x + 2, -y, -z) N—H···N (x-1, y + 1, z)] are drawn as dashed lines.
3-Oxo-5-(piperidin-1-yl)-2,3-dihydro-1H-pyrazole-4-carbonitrile top
Crystal data top
C9H12N4OZ = 2
Mr = 192.23F(000) = 204
Triclinic, P1Dx = 1.358 Mg m3
Hall symbol: -P 1Melting point: 527 K
a = 7.2667 (5) ÅCu Kα radiation, λ = 1.54178 Å
b = 7.9624 (5) ÅCell parameters from 3129 reflections
c = 8.8306 (8) Åθ = 5–71°
α = 89.280 (6)°µ = 0.77 mm1
β = 75.934 (7)°T = 150 K
γ = 71.906 (6)°Block, colourless
V = 470.01 (6) Å30.22 × 0.19 × 0.13 mm
Data collection top
Oxford Diffraction Gemini
diffractometer
1803 independent reflections
Radiation source: fine-focus sealed tube1627 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.013
ω/2θ scansθmax = 70.9°, θmin = 5.2°
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2006)
h = 88
Tmin = 0.849, Tmax = 0.906k = 99
5083 measured reflectionsl = 1010
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) = 0.166H-atom parameters constrained
S = 1.11 w = 1/[σ2(Fo2) + (0.0971P)2 + 0.2641P]
where P = (Fo2 + 2Fc2)/3
1803 reflections(Δ/σ)max < 0.001
127 parametersΔρmax = 0.74 e Å3
0 restraintsΔρmin = 0.61 e Å3
Crystal data top
C9H12N4Oγ = 71.906 (6)°
Mr = 192.23V = 470.01 (6) Å3
Triclinic, P1Z = 2
a = 7.2667 (5) ÅCu Kα radiation
b = 7.9624 (5) ŵ = 0.77 mm1
c = 8.8306 (8) ÅT = 150 K
α = 89.280 (6)°0.22 × 0.19 × 0.13 mm
β = 75.934 (7)°
Data collection top
Oxford Diffraction Gemini
diffractometer
1803 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2006)
1627 reflections with I > 2σ(I)
Tmin = 0.849, Tmax = 0.906Rint = 0.013
5083 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0570 restraints
wR(F2) = 0.166H-atom parameters constrained
S = 1.11Δρmax = 0.74 e Å3
1803 reflectionsΔρmin = 0.61 e Å3
127 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems open-flow nitrogen cryostat (Cosier & Glazer, 1986) with a nominal stability of 0.1 K.

Cosier, J. & Glazer, A.M., 1986. J. Appl. Cryst. 105 107.

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
O11.2334 (2)0.03312 (18)0.39572 (17)0.0334 (4)
N10.8756 (2)0.6211 (2)0.2901 (2)0.0306 (4)
N20.8011 (2)0.3667 (2)0.38329 (19)0.0273 (4)
H20.67300.41300.40700.033*
N30.9078 (2)0.1884 (2)0.39566 (19)0.0285 (4)
H30.85630.10430.41460.034*
N41.4774 (3)0.3703 (3)0.2487 (2)0.0397 (5)
C11.0124 (3)0.7167 (3)0.2139 (3)0.0349 (5)
H1A1.14960.64180.20140.042*
H1B0.99070.82180.27890.042*
C20.9771 (4)0.7692 (3)0.0547 (3)0.0394 (5)
H2A1.01650.66350.01440.047*
H2B1.05960.84130.00940.047*
C30.7585 (4)0.8722 (3)0.0673 (3)0.0424 (6)
H3A0.72340.98510.12530.051*
H3B0.73860.89540.03660.051*
C40.6237 (3)0.7685 (3)0.1497 (3)0.0380 (5)
H4A0.48470.83900.16280.046*
H4B0.64910.66100.08650.046*
C50.6632 (3)0.7218 (3)0.3084 (2)0.0333 (5)
H5A0.62820.82930.37420.040*
H5B0.58080.65170.35880.040*
C60.9374 (3)0.4540 (2)0.3267 (2)0.0249 (4)
C71.1293 (3)0.3363 (2)0.3210 (2)0.0252 (4)
C81.1054 (3)0.1702 (2)0.3729 (2)0.0262 (4)
C91.3185 (3)0.3601 (3)0.2816 (2)0.0289 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0258 (7)0.0273 (7)0.0420 (8)0.0030 (6)0.0067 (6)0.0098 (6)
N10.0276 (9)0.0285 (9)0.0356 (9)0.0062 (7)0.0116 (7)0.0092 (7)
N20.0200 (8)0.0254 (8)0.0343 (9)0.0032 (6)0.0082 (6)0.0071 (6)
N30.0254 (8)0.0232 (8)0.0371 (9)0.0070 (7)0.0092 (7)0.0072 (6)
N40.0283 (10)0.0412 (11)0.0545 (11)0.0131 (8)0.0169 (8)0.0118 (8)
C10.0353 (11)0.0276 (10)0.0462 (12)0.0126 (9)0.0152 (9)0.0095 (9)
C20.0445 (13)0.0297 (11)0.0387 (12)0.0095 (9)0.0038 (9)0.0084 (9)
C30.0532 (14)0.0321 (11)0.0331 (11)0.0007 (10)0.0116 (10)0.0076 (9)
C40.0364 (11)0.0332 (11)0.0388 (11)0.0013 (9)0.0154 (9)0.0018 (9)
C50.0295 (11)0.0274 (10)0.0382 (11)0.0016 (8)0.0093 (8)0.0061 (8)
C60.0271 (10)0.0274 (10)0.0215 (8)0.0078 (8)0.0095 (7)0.0035 (7)
C70.0244 (9)0.0259 (10)0.0257 (9)0.0066 (7)0.0090 (7)0.0029 (7)
C80.0255 (9)0.0261 (9)0.0252 (9)0.0050 (7)0.0071 (7)0.0016 (7)
C90.0298 (11)0.0269 (10)0.0318 (10)0.0070 (8)0.0141 (8)0.0065 (8)
Geometric parameters (Å, º) top
O1—C81.246 (2)C2—H2A0.9700
N1—C61.329 (3)C2—H2B0.9700
N1—C11.467 (3)C3—C41.520 (3)
N1—C51.471 (3)C3—H3A0.9700
N2—C61.376 (2)C3—H3B0.9700
N2—N31.408 (2)C4—C51.517 (3)
N2—H20.8600C4—H4A0.9700
N3—C81.362 (3)C4—H4B0.9700
N3—H30.8600C5—H5A0.9700
N4—C91.148 (3)C5—H5B0.9700
C1—C21.520 (3)C6—C71.407 (3)
C1—H1A0.9700C7—C91.406 (3)
C1—H1B0.9700C7—C81.442 (3)
C2—C31.521 (3)
C6—N1—C1123.24 (17)C2—C3—H3B109.5
C6—N1—C5122.91 (17)H3A—C3—H3B108.1
C1—N1—C5113.60 (16)C5—C4—C3109.84 (19)
C6—N2—N3108.06 (14)C5—C4—H4A109.7
C6—N2—H2126.0C3—C4—H4A109.7
N3—N2—H2126.0C5—C4—H4B109.7
C8—N3—N2109.28 (15)C3—C4—H4B109.7
C8—N3—H3125.4H4A—C4—H4B108.2
N2—N3—H3125.4N1—C5—C4110.09 (17)
N1—C1—C2109.99 (17)N1—C5—H5A109.6
N1—C1—H1A109.7C4—C5—H5A109.6
C2—C1—H1A109.7N1—C5—H5B109.6
N1—C1—H1B109.7C4—C5—H5B109.6
C2—C1—H1B109.7H5A—C5—H5B108.2
H1A—C1—H1B108.2N1—C6—N2120.17 (17)
C1—C2—C3111.40 (19)N1—C6—C7132.01 (18)
C1—C2—H2A109.3N2—C6—C7107.82 (16)
C3—C2—H2A109.3C9—C7—C6131.41 (17)
C1—C2—H2B109.3C9—C7—C8121.20 (17)
C3—C2—H2B109.3C6—C7—C8107.35 (16)
H2A—C2—H2B108.0O1—C8—N3124.15 (18)
C4—C3—C2110.68 (18)O1—C8—C7129.26 (18)
C4—C3—H3A109.5N3—C8—C7106.58 (16)
C2—C3—H3A109.5N4—C9—C7176.5 (2)
C4—C3—H3B109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···N4i0.862.322.875 (3)123
N3—H3···O1ii0.862.072.772 (2)138
C4—H4A···O1iii0.972.543.258 (3)131
Symmetry codes: (i) x1, y, z; (ii) x+2, y, z+1; (iii) x1, y+1, z.

Experimental details

Crystal data
Chemical formulaC9H12N4O
Mr192.23
Crystal system, space groupTriclinic, P1
Temperature (K)150
a, b, c (Å)7.2667 (5), 7.9624 (5), 8.8306 (8)
α, β, γ (°)89.280 (6), 75.934 (7), 71.906 (6)
V3)470.01 (6)
Z2
Radiation typeCu Kα
µ (mm1)0.77
Crystal size (mm)0.22 × 0.19 × 0.13
Data collection
DiffractometerOxford Diffraction Gemini
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2006)
Tmin, Tmax0.849, 0.906
No. of measured, independent and
observed [I > 2σ(I)] reflections
5083, 1803, 1627
Rint0.013
(sin θ/λ)max1)0.613
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.166, 1.11
No. of reflections1803
No. of parameters127
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.74, 0.61

Computer programs: Gemini User Manual (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···N4i0.862.322.875 (3)123
N3—H3···O1ii0.862.072.772 (2)138
C4—H4A···O1iii0.972.543.258 (3)131
Symmetry codes: (i) x1, y, z; (ii) x+2, y, z+1; (iii) x1, y+1, z.
 

Acknowledgements

The authors thank Universiti Kebangsaan Malaysia for providing facilities and the Ministry of Higher Education Malaysia for the research fund (UKM-GGPM-KPB-098–2010). A scholarship from the Libyan Government to WMA is also greatly appreciated.

References

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
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