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

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3,4-Di­methyl-1-phenyl­pyrano[2,3-c]pyrazol-6(1H)-one

aDepartment of Chemistry, Islamia University, Bahawalpur, Pakistan, bDepartment of Physics, University of Sargodha, Sargodha, Pakistan, and cApplied Chemistry Research Center, PCSIR Laboratories Complex, Lahore 54600, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 26 March 2011; accepted 27 March 2011; online 31 March 2011)

In the title compound, C14H12N2O2, the dihedral angle between the phenyl ring and the 3,4-dimethyl­pyrano[2,3-c]pyrazol-6(1H)-one system is 7.28 (6)°. An intra­molecular C—H⋯O inter­action generates an S(6) ring. In the crystal, the mol­ecules are linked by C—H⋯O hydrogen bonds, forming C(8) chains. C–H⋯π and ππ inter­actions [centroid–centroid separation = 3.6374 (12) Å] further consolidate the packing.

Related literature

For a related structure, see: Ramsay & Steel (1985)[Ramsay, C. G. & Steel, P. J. (1985). Acta Cryst. C41, 135-136.]. For background to the pyrano[2,3-c]pyrazol-6-one ring system, see: Abdallah & Zaki (1999[Abdallah, N. A. & Zaki, M. E. A. (1999). Acta Pharm. 49, 159-170.]); Huang et al. (1992[Huang, L.-J., Hour, M.-J., Teng, C.-M. & Kuo, S.-C. (1992). Chem. Pharm. Bull. 40, 2547-2551.]); Khan et al. (1982[Khan, M. A., Cosenza, A. G. & Ellis, G. P. (1982). J. Heterocycl. Chem. 19, 1077-1085.]); Kuo et al. (1984[Kuo, S.-C., Huang, L.-J. & Nakamura, H. (1984). J. Med. Chem. 27, 539-544.]); Ramsay & Steel (1985)[Ramsay, C. G. & Steel, P. J. (1985). Acta Cryst. C41, 135-136.]; Samaritoni et al. (2007[Samaritoni, G. J., Thornburgh, S., Graupner, P. R. & Cooper, D. H. (2007). J. Heterocycl. Chem. 44, 1389-1393.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12N2O2

  • Mr = 240.26

  • Monoclinic, C 2/c

  • a = 15.1231 (9) Å

  • b = 13.3558 (8) Å

  • c = 13.8684 (8) Å

  • β = 120.965 (2)°

  • V = 2401.9 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 296 K

  • 0.35 × 0.25 × 0.25 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.975, Tmax = 0.982

  • 9214 measured reflections

  • 2171 independent reflections

  • 1382 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.140

  • S = 1.02

  • 2171 reflections

  • 165 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 is the centroid of the C1–C6 phenyl ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3⋯O2i 0.93 2.51 3.407 (3) 163
C6—H6⋯O1 0.93 2.29 2.938 (3) 126
C14—H14CCg3ii 0.96 2.75 3.506 (2) 136
Symmetry codes: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) -x, -y+1, -z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

The parent ring system pyrano[2,3-c]pyrazol-6-one is an isostere of coumarin. A number of its derivatives have been prepared from corresponding hydrazines and beta ketoesters (Khan et al., 1982, Samaritoni et al., 2007). It has been shown that these contain analgesic and anti-inflammatory activities (Kuo et al., 1984, Abdallah & Zaki, 1999) and while others are tested for their antiplatelet activity (Huang et al., 1992). The title compound (I, Fig. 1) has been synthesized and its crystal structure is being reported here.

The crystal structure of (II) i.e., 3,4-dimethyl-1-(2-pyridyl)pyrano(2,3 - c)pyrazol-6(1H)-one (Ramsay & Steel, 1983) has been published which differs from (I) due to pyridal attachment instead of phenyl and hence is closely related.

In (I) the phyenyl ring A (C1–C6) and 3,4-dimethylpyrano[2,3-c]pyrazol -6(1H)-one moiety are almost planar with r. m. s. deviations of 0.003 and 0.023 Å, respectively. The dihedral angle between A/B is 7.28 (6)°. The molecules are linked by C(8) polymeric chains (Bernstein et al., 1995) due to H-boning of C—H···O type (Table 1, Fig. 2). An intramolecular H-bonding and a C—H···π interaction (Table 1) also play an important role in stabilizing the molecules. There also exist π···π interactions between the pyrazole rings at a distance of 3.6374 (12) Å.

Related literature top

For a related structure, see: Ramsay & Steel (1985). For background to the pyrano[2,3-c]pyrazol-6-one ring system, see: Abdallah & Zaki (1999); Huang et al. (1992); Khan et al. (1982); Kuo et al. (1984); Ramsay & Steel (1985); Samaritoni et al. (2007). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

A mixture of 3-methyl-1-phenylpyrazol-5-one (17.4 g, 0.1 mol) and ethyl acetoacetate (13 g, 0.1 mol) was heated at 413 K (oil bath) for an hour, cooled and triturated with 200 ml of pet. ether (bp. 313–333 K) and filtered to give the title compound. Light brown rods of (I) were obtained on recrystallization from ethanol. Yield 10.8 g, 45%: m.p. 415 K

Refinement top

The H-atoms were positioned geometrically (C–H = 0.93–0.96 Å) and refined as riding with Uiso(H) = xUeq(C), where x = 1.5 for methyl and x = 1.2 for aryl H-atoms.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram of the title compound showing that polymeric chains are formed.
3,4-Dimethyl-1-phenylpyrano[2,3-c]pyrazol-6(1H)-one top
Crystal data top
C14H12N2O2F(000) = 1008
Mr = 240.26Dx = 1.329 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 1382 reflections
a = 15.1231 (9) Åθ = 2.2–25.3°
b = 13.3558 (8) ŵ = 0.09 mm1
c = 13.8684 (8) ÅT = 296 K
β = 120.965 (2)°Rod, light brown
V = 2401.9 (3) Å30.35 × 0.25 × 0.25 mm
Z = 8
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2171 independent reflections
Radiation source: fine-focus sealed tube1382 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
Detector resolution: 8.10 pixels mm-1θmax = 25.3°, θmin = 2.2°
ω scansh = 1814
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
k = 1516
Tmin = 0.975, Tmax = 0.982l = 916
9214 measured 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)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0723P)2 + 0.5405P]
where P = (Fo2 + 2Fc2)/3
2171 reflections(Δ/σ)max < 0.001
165 parametersΔρmax = 0.15 e Å3
0 restraintsΔρmin = 0.19 e Å3
Crystal data top
C14H12N2O2V = 2401.9 (3) Å3
Mr = 240.26Z = 8
Monoclinic, C2/cMo Kα radiation
a = 15.1231 (9) ŵ = 0.09 mm1
b = 13.3558 (8) ÅT = 296 K
c = 13.8684 (8) Å0.35 × 0.25 × 0.25 mm
β = 120.965 (2)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2171 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
1382 reflections with I > 2σ(I)
Tmin = 0.975, Tmax = 0.982Rint = 0.032
9214 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.140H-atom parameters constrained
S = 1.02Δρmax = 0.15 e Å3
2171 reflectionsΔρmin = 0.19 e Å3
165 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
O10.01582 (9)0.63464 (9)0.13521 (10)0.0584 (5)
O20.07464 (12)0.77525 (12)0.09062 (16)0.0994 (7)
N10.09619 (12)0.47598 (11)0.16813 (13)0.0526 (6)
N20.06513 (14)0.37672 (12)0.14972 (16)0.0689 (7)
C10.20381 (14)0.49922 (15)0.22105 (15)0.0526 (7)
C20.27219 (16)0.42241 (17)0.24254 (18)0.0661 (8)
C30.37688 (16)0.44318 (19)0.2968 (2)0.0794 (9)
C40.41168 (17)0.5391 (2)0.3279 (2)0.0825 (9)
C50.34341 (16)0.61512 (19)0.30539 (19)0.0770 (9)
C60.23861 (15)0.59574 (16)0.25142 (17)0.0613 (8)
C70.01255 (14)0.53448 (14)0.13093 (15)0.0484 (7)
C80.08080 (15)0.68528 (17)0.08827 (18)0.0659 (8)
C90.17132 (15)0.62522 (17)0.04570 (17)0.0638 (8)
C100.17218 (14)0.52456 (16)0.04351 (15)0.0537 (7)
C110.07438 (14)0.47628 (14)0.08801 (16)0.0519 (7)
C120.03607 (17)0.37748 (16)0.10228 (19)0.0657 (8)
C130.0944 (2)0.28099 (17)0.0706 (3)0.1025 (13)
C140.27056 (15)0.46714 (18)0.00325 (19)0.0709 (8)
H20.248470.357270.220900.0793*
H30.423640.391620.312120.0953*
H40.481980.552480.364450.0990*
H50.367390.680280.326390.0924*
H60.192150.647660.235860.0736*
H90.234160.657970.017490.0766*
H13A0.048340.226800.081830.1536*
H13B0.148320.283360.006990.1536*
H13C0.123970.270810.116740.1536*
H14A0.326440.512650.022760.1064*
H14B0.265420.420520.052100.1064*
H14C0.283050.431350.069140.1064*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0380 (8)0.0474 (9)0.0769 (9)0.0008 (6)0.0203 (7)0.0016 (6)
O20.0515 (10)0.0514 (11)0.1565 (16)0.0033 (8)0.0259 (10)0.0053 (10)
N10.0409 (9)0.0431 (10)0.0687 (10)0.0025 (8)0.0245 (8)0.0023 (7)
N20.0509 (12)0.0454 (11)0.1012 (13)0.0024 (8)0.0325 (10)0.0020 (9)
C10.0375 (11)0.0555 (13)0.0584 (11)0.0036 (9)0.0201 (9)0.0015 (9)
C20.0503 (13)0.0581 (14)0.0807 (14)0.0098 (11)0.0272 (11)0.0040 (10)
C30.0478 (14)0.0753 (17)0.1009 (17)0.0200 (13)0.0282 (13)0.0069 (13)
C40.0374 (12)0.0844 (18)0.1021 (18)0.0021 (13)0.0191 (12)0.0092 (14)
C50.0428 (13)0.0728 (16)0.0992 (17)0.0039 (12)0.0249 (12)0.0147 (13)
C60.0401 (12)0.0550 (14)0.0797 (13)0.0014 (10)0.0243 (10)0.0064 (10)
C70.0422 (11)0.0434 (12)0.0572 (11)0.0013 (9)0.0238 (9)0.0009 (9)
C80.0431 (12)0.0519 (14)0.0856 (14)0.0050 (11)0.0208 (11)0.0010 (11)
C90.0357 (11)0.0631 (15)0.0793 (14)0.0022 (10)0.0201 (10)0.0039 (11)
C100.0411 (11)0.0572 (13)0.0587 (11)0.0032 (9)0.0228 (9)0.0021 (9)
C110.0410 (11)0.0496 (12)0.0620 (12)0.0029 (9)0.0244 (9)0.0002 (9)
C120.0525 (13)0.0489 (14)0.0905 (15)0.0057 (10)0.0331 (12)0.0013 (10)
C130.0688 (17)0.0521 (16)0.166 (3)0.0132 (13)0.0457 (17)0.0009 (15)
C140.0444 (12)0.0789 (16)0.0838 (14)0.0161 (11)0.0289 (11)0.0101 (12)
Geometric parameters (Å, º) top
O1—C71.339 (2)C10—C111.430 (3)
O1—C81.427 (3)C10—C141.493 (3)
O2—C81.204 (3)C11—C121.414 (3)
N1—N21.386 (2)C12—C131.494 (4)
N1—C11.433 (3)C2—H20.9300
N1—C71.344 (3)C3—H30.9300
N2—C121.319 (4)C4—H40.9300
C1—C21.376 (3)C5—H50.9300
C1—C61.374 (3)C6—H60.9300
C2—C31.387 (4)C9—H90.9300
C3—C41.368 (4)C13—H13A0.9600
C4—C51.365 (4)C13—H13B0.9600
C5—C61.385 (4)C13—H13C0.9600
C7—C111.372 (3)C14—H14A0.9600
C8—C91.426 (3)C14—H14B0.9600
C9—C101.345 (3)C14—H14C0.9600
C7—O1—C8116.58 (17)N2—C12—C13119.9 (2)
N2—N1—C1119.31 (17)C11—C12—C13128.8 (3)
N2—N1—C7108.83 (18)C1—C2—H2120.00
C1—N1—C7131.86 (16)C3—C2—H2120.00
N1—N2—C12106.32 (18)C2—C3—H3120.00
N1—C1—C2118.57 (18)C4—C3—H3120.00
N1—C1—C6121.0 (2)C3—C4—H4120.00
C2—C1—C6120.4 (2)C5—C4—H4120.00
C1—C2—C3119.3 (2)C4—C5—H5120.00
C2—C3—C4120.3 (2)C6—C5—H5120.00
C3—C4—C5120.1 (3)C1—C6—H6120.00
C4—C5—C6120.4 (2)C5—C6—H6120.00
C1—C6—C5119.5 (2)C8—C9—H9118.00
O1—C7—N1123.92 (19)C10—C9—H9118.00
O1—C7—C11126.2 (2)C12—C13—H13A109.00
N1—C7—C11109.87 (17)C12—C13—H13B109.00
O1—C8—O2114.4 (2)C12—C13—H13C109.00
O1—C8—C9117.49 (19)H13A—C13—H13B109.00
O2—C8—C9128.1 (2)H13A—C13—H13C109.00
C8—C9—C10124.6 (2)H13B—C13—H13C109.00
C9—C10—C11116.4 (2)C10—C14—H14A109.00
C9—C10—C14121.3 (2)C10—C14—H14B109.00
C11—C10—C14122.28 (19)C10—C14—H14C109.00
C7—C11—C10118.64 (18)H14A—C14—H14B109.00
C7—C11—C12103.7 (2)H14A—C14—H14C109.00
C10—C11—C12137.7 (2)H14B—C14—H14C109.00
N2—C12—C11111.3 (2)
C8—O1—C7—N1177.83 (18)C1—C2—C3—C40.5 (4)
C8—O1—C7—C111.5 (3)C2—C3—C4—C50.2 (4)
C7—O1—C8—O2177.76 (19)C3—C4—C5—C60.3 (4)
C7—O1—C8—C92.7 (3)C4—C5—C6—C10.3 (3)
C1—N1—N2—C12179.03 (18)O1—C7—C11—C100.4 (3)
C7—N1—N2—C120.1 (2)O1—C7—C11—C12179.28 (19)
N2—N1—C1—C25.9 (3)N1—C7—C11—C10179.82 (17)
N2—N1—C1—C6173.10 (19)N1—C7—C11—C120.1 (2)
C7—N1—C1—C2175.1 (2)O1—C8—C9—C102.2 (3)
C7—N1—C1—C65.8 (3)O2—C8—C9—C10178.3 (2)
N2—N1—C7—O1179.24 (17)C8—C9—C10—C110.3 (3)
N2—N1—C7—C110.2 (2)C8—C9—C10—C14179.6 (2)
C1—N1—C7—O11.7 (3)C9—C10—C11—C71.0 (3)
C1—N1—C7—C11178.87 (19)C9—C10—C11—C12178.6 (2)
N1—N2—C12—C110.1 (2)C14—C10—C11—C7179.04 (19)
N1—N2—C12—C13179.6 (2)C14—C10—C11—C121.4 (4)
N1—C1—C2—C3178.0 (2)C7—C11—C12—N20.0 (3)
C6—C1—C2—C31.0 (3)C7—C11—C12—C13179.5 (3)
N1—C1—C6—C5178.11 (19)C10—C11—C12—N2179.6 (2)
C2—C1—C6—C50.9 (3)C10—C11—C12—C130.1 (5)
Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C1–C6 phenyl ring.
D—H···AD—HH···AD···AD—H···A
C3—H3···O2i0.932.513.407 (3)163
C6—H6···O10.932.292.938 (3)126
C14—H14C···Cg3ii0.962.753.506 (2)136
Symmetry codes: (i) x+1/2, y1/2, z+1/2; (ii) x, y+1, z.

Experimental details

Crystal data
Chemical formulaC14H12N2O2
Mr240.26
Crystal system, space groupMonoclinic, C2/c
Temperature (K)296
a, b, c (Å)15.1231 (9), 13.3558 (8), 13.8684 (8)
β (°) 120.965 (2)
V3)2401.9 (3)
Z8
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.35 × 0.25 × 0.25
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.975, 0.982
No. of measured, independent and
observed [I > 2σ(I)] reflections
9214, 2171, 1382
Rint0.032
(sin θ/λ)max1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.140, 1.02
No. of reflections2171
No. of parameters165
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.15, 0.19

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg3 is the centroid of the C1–C6 phenyl ring.
D—H···AD—HH···AD···AD—H···A
C3—H3···O2i0.932.513.407 (3)163
C6—H6···O10.932.292.938 (3)126
C14—H14C···Cg3ii0.962.753.506 (2)136
Symmetry codes: (i) x+1/2, y1/2, z+1/2; (ii) x, y+1, z.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. The authors also acknowledge the technical support provided by Bana Inter­national, Karachi, Pakistan.

References

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