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

Ahmad, N.; Tahir, M.N.; Khan, M.A.; Ather, A.Q.; Khan, M.N.

doi:10.1107/S1600536811011317

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 4| April 2011| Page o1021

doi:10.1107/S1600536811011317

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

Neman Ahmad,^a M. Nawaz Tahir,^b ^* Misbahul Ain Khan,^a Abdul Qayyum Ather ^c and Muhammad Naeem Khan ^c

^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 π–π interactions [centroid–centroid separation = 3.6374 (12) Å] further consolidate the packing.

Related literature

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

Crystal data

C₁₄H₁₂N₂O₂
M_r = 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 ) T_min = 0.975, T_max = 0.982
9214 measured reflections
2171 independent reflections
1382 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.140
S = 1.02
2171 reflections
165 parameters
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −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	D⋯A	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—H14C⋯Cg3ⁱⁱ	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 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811011317/hb5827sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811011317/hb5827Isup2.hkl

checkCIF report

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

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

	Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level.
	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

C₁₄H₁₂N₂O₂	F(000) = 1008
M_r = 240.26	D_x = 1.329 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1382 reflections
a = 15.1231 (9) Å	θ = 2.2–25.3°
b = 13.3558 (8) Å	µ = 0.09 mm⁻¹
c = 13.8684 (8) Å	T = 296 K
β = 120.965 (2)°	Rod, light brown
V = 2401.9 (3) Å³	0.35 × 0.25 × 0.25 mm
Z = 8

Data collection top

Bruker Kappa APEXII CCD diffractometer	2171 independent reflections
Radiation source: fine-focus sealed tube	1382 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
Detector resolution: 8.10 pixels mm^-1	θ_max = 25.3°, θ_min = 2.2°
ω scans	h = −18→14
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −15→16
T_min = 0.975, T_max = 0.982	l = −9→16
9214 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.140	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0723P)² + 0.5405P] where P = (F_o² + 2F_c²)/3
2171 reflections	(Δ/σ)_max < 0.001
165 parameters	Δρ_max = 0.15 e Å⁻³
0 restraints	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₁₄H₁₂N₂O₂	V = 2401.9 (3) Å³
M_r = 240.26	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 15.1231 (9) Å	µ = 0.09 mm⁻¹
b = 13.3558 (8) Å	T = 296 K
c = 13.8684 (8) Å	0.35 × 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)
T_min = 0.975, T_max = 0.982	R_int = 0.032
9214 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.140	H-atom parameters constrained
S = 1.02	Δρ_max = 0.15 e Å⁻³
2171 reflections	Δρ_min = −0.19 e Å⁻³
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

	x	y	z	U_iso*/U_eq
O1	0.01582 (9)	0.63464 (9)	0.13521 (10)	0.0584 (5)
O2	−0.07464 (12)	0.77525 (12)	0.09062 (16)	0.0994 (7)
N1	0.09619 (12)	0.47598 (11)	0.16813 (13)	0.0526 (6)
N2	0.06513 (14)	0.37672 (12)	0.14972 (16)	0.0689 (7)
C1	0.20381 (14)	0.49922 (15)	0.22105 (15)	0.0526 (7)
C2	0.27219 (16)	0.42241 (17)	0.24254 (18)	0.0661 (8)
C3	0.37688 (16)	0.44318 (19)	0.2968 (2)	0.0794 (9)
C4	0.41168 (17)	0.5391 (2)	0.3279 (2)	0.0825 (9)
C5	0.34341 (16)	0.61512 (19)	0.30539 (19)	0.0770 (9)
C6	0.23861 (15)	0.59574 (16)	0.25142 (17)	0.0613 (8)
C7	0.01255 (14)	0.53448 (14)	0.13093 (15)	0.0484 (7)
C8	−0.08080 (15)	0.68528 (17)	0.08827 (18)	0.0659 (8)
C9	−0.17132 (15)	0.62522 (17)	0.04570 (17)	0.0638 (8)
C10	−0.17218 (14)	0.52456 (16)	0.04351 (15)	0.0537 (7)
C11	−0.07438 (14)	0.47628 (14)	0.08801 (16)	0.0519 (7)
C12	−0.03607 (17)	0.37748 (16)	0.10228 (19)	0.0657 (8)
C13	−0.0944 (2)	0.28099 (17)	0.0706 (3)	0.1025 (13)
C14	−0.27056 (15)	0.46714 (18)	−0.00325 (19)	0.0709 (8)
H2	0.24847	0.35727	0.22090	0.0793*
H3	0.42364	0.39162	0.31212	0.0953*
H4	0.48198	0.55248	0.36445	0.0990*
H5	0.36739	0.68028	0.32639	0.0924*
H6	0.19215	0.64766	0.23586	0.0736*
H9	−0.23416	0.65797	0.01749	0.0766*
H13A	−0.04834	0.22680	0.08183	0.1536*
H13B	−0.14832	0.28336	−0.00699	0.1536*
H13C	−0.12397	0.27081	0.11674	0.1536*
H14A	−0.32644	0.51265	−0.02276	0.1064*
H14B	−0.26542	0.42052	0.05210	0.1064*
H14C	−0.28305	0.43135	−0.06914	0.1064*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0380 (8)	0.0474 (9)	0.0769 (9)	0.0008 (6)	0.0203 (7)	−0.0016 (6)
O2	0.0515 (10)	0.0514 (11)	0.1565 (16)	0.0033 (8)	0.0259 (10)	−0.0053 (10)
N1	0.0409 (9)	0.0431 (10)	0.0687 (10)	0.0025 (8)	0.0245 (8)	0.0023 (7)
N2	0.0509 (12)	0.0454 (11)	0.1012 (13)	−0.0024 (8)	0.0325 (10)	0.0020 (9)
C1	0.0375 (11)	0.0555 (13)	0.0584 (11)	0.0036 (9)	0.0201 (9)	0.0015 (9)
C2	0.0503 (13)	0.0581 (14)	0.0807 (14)	0.0098 (11)	0.0272 (11)	0.0040 (10)
C3	0.0478 (14)	0.0753 (17)	0.1009 (17)	0.0200 (13)	0.0282 (13)	0.0069 (13)
C4	0.0374 (12)	0.0844 (18)	0.1021 (18)	0.0021 (13)	0.0191 (12)	−0.0092 (14)
C5	0.0428 (13)	0.0728 (16)	0.0992 (17)	−0.0039 (12)	0.0249 (12)	−0.0147 (13)
C6	0.0401 (12)	0.0550 (14)	0.0797 (13)	0.0014 (10)	0.0243 (10)	−0.0064 (10)
C7	0.0422 (11)	0.0434 (12)	0.0572 (11)	0.0013 (9)	0.0238 (9)	0.0009 (9)
C8	0.0431 (12)	0.0519 (14)	0.0856 (14)	0.0050 (11)	0.0208 (11)	−0.0010 (11)
C9	0.0357 (11)	0.0631 (15)	0.0793 (14)	0.0022 (10)	0.0201 (10)	−0.0039 (11)
C10	0.0411 (11)	0.0572 (13)	0.0587 (11)	−0.0032 (9)	0.0228 (9)	−0.0021 (9)
C11	0.0410 (11)	0.0496 (12)	0.0620 (12)	−0.0029 (9)	0.0244 (9)	−0.0002 (9)
C12	0.0525 (13)	0.0489 (14)	0.0905 (15)	−0.0057 (10)	0.0331 (12)	0.0013 (10)
C13	0.0688 (17)	0.0521 (16)	0.166 (3)	−0.0132 (13)	0.0457 (17)	−0.0009 (15)
C14	0.0444 (12)	0.0789 (16)	0.0838 (14)	−0.0161 (11)	0.0289 (11)	−0.0101 (12)

Geometric parameters (Å, º) top

O1—C7	1.339 (2)	C10—C11	1.430 (3)
O1—C8	1.427 (3)	C10—C14	1.493 (3)
O2—C8	1.204 (3)	C11—C12	1.414 (3)
N1—N2	1.386 (2)	C12—C13	1.494 (4)
N1—C1	1.433 (3)	C2—H2	0.9300
N1—C7	1.344 (3)	C3—H3	0.9300
N2—C12	1.319 (4)	C4—H4	0.9300
C1—C2	1.376 (3)	C5—H5	0.9300
C1—C6	1.374 (3)	C6—H6	0.9300
C2—C3	1.387 (4)	C9—H9	0.9300
C3—C4	1.368 (4)	C13—H13A	0.9600
C4—C5	1.365 (4)	C13—H13B	0.9600
C5—C6	1.385 (4)	C13—H13C	0.9600
C7—C11	1.372 (3)	C14—H14A	0.9600
C8—C9	1.426 (3)	C14—H14B	0.9600
C9—C10	1.345 (3)	C14—H14C	0.9600

C7—O1—C8	116.58 (17)	N2—C12—C13	119.9 (2)
N2—N1—C1	119.31 (17)	C11—C12—C13	128.8 (3)
N2—N1—C7	108.83 (18)	C1—C2—H2	120.00
C1—N1—C7	131.86 (16)	C3—C2—H2	120.00
N1—N2—C12	106.32 (18)	C2—C3—H3	120.00
N1—C1—C2	118.57 (18)	C4—C3—H3	120.00
N1—C1—C6	121.0 (2)	C3—C4—H4	120.00
C2—C1—C6	120.4 (2)	C5—C4—H4	120.00
C1—C2—C3	119.3 (2)	C4—C5—H5	120.00
C2—C3—C4	120.3 (2)	C6—C5—H5	120.00
C3—C4—C5	120.1 (3)	C1—C6—H6	120.00
C4—C5—C6	120.4 (2)	C5—C6—H6	120.00
C1—C6—C5	119.5 (2)	C8—C9—H9	118.00
O1—C7—N1	123.92 (19)	C10—C9—H9	118.00
O1—C7—C11	126.2 (2)	C12—C13—H13A	109.00
N1—C7—C11	109.87 (17)	C12—C13—H13B	109.00
O1—C8—O2	114.4 (2)	C12—C13—H13C	109.00
O1—C8—C9	117.49 (19)	H13A—C13—H13B	109.00
O2—C8—C9	128.1 (2)	H13A—C13—H13C	109.00
C8—C9—C10	124.6 (2)	H13B—C13—H13C	109.00
C9—C10—C11	116.4 (2)	C10—C14—H14A	109.00
C9—C10—C14	121.3 (2)	C10—C14—H14B	109.00
C11—C10—C14	122.28 (19)	C10—C14—H14C	109.00
C7—C11—C10	118.64 (18)	H14A—C14—H14B	109.00
C7—C11—C12	103.7 (2)	H14A—C14—H14C	109.00
C10—C11—C12	137.7 (2)	H14B—C14—H14C	109.00
N2—C12—C11	111.3 (2)

C8—O1—C7—N1	177.83 (18)	C1—C2—C3—C4	−0.5 (4)
C8—O1—C7—C11	−1.5 (3)	C2—C3—C4—C5	−0.2 (4)
C7—O1—C8—O2	−177.76 (19)	C3—C4—C5—C6	0.3 (4)
C7—O1—C8—C9	2.7 (3)	C4—C5—C6—C1	0.3 (3)
C1—N1—N2—C12	179.03 (18)	O1—C7—C11—C10	−0.4 (3)
C7—N1—N2—C12	−0.1 (2)	O1—C7—C11—C12	179.28 (19)
N2—N1—C1—C2	5.9 (3)	N1—C7—C11—C10	−179.82 (17)
N2—N1—C1—C6	−173.10 (19)	N1—C7—C11—C12	−0.1 (2)
C7—N1—C1—C2	−175.1 (2)	O1—C8—C9—C10	−2.2 (3)
C7—N1—C1—C6	5.8 (3)	O2—C8—C9—C10	178.3 (2)
N2—N1—C7—O1	−179.24 (17)	C8—C9—C10—C11	0.3 (3)
N2—N1—C7—C11	0.2 (2)	C8—C9—C10—C14	−179.6 (2)
C1—N1—C7—O1	1.7 (3)	C9—C10—C11—C7	1.0 (3)
C1—N1—C7—C11	−178.87 (19)	C9—C10—C11—C12	−178.6 (2)
N1—N2—C12—C11	0.1 (2)	C14—C10—C11—C7	−179.04 (19)
N1—N2—C12—C13	179.6 (2)	C14—C10—C11—C12	1.4 (4)
N1—C1—C2—C3	−178.0 (2)	C7—C11—C12—N2	0.0 (3)
C6—C1—C2—C3	1.0 (3)	C7—C11—C12—C13	−179.5 (3)
N1—C1—C6—C5	178.11 (19)	C10—C11—C12—N2	179.6 (2)
C2—C1—C6—C5	−0.9 (3)	C10—C11—C12—C13	0.1 (5)

Hydrogen-bond geometry (Å, º) top

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

D—H···A	D—H	H···A	D···A	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—H14C···Cg3ⁱⁱ	0.96	2.75	3.506 (2)	136

Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x, −y+1, −z.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₂N₂O₂
M_r	240.26
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	296
a, b, c (Å)	15.1231 (9), 13.3558 (8), 13.8684 (8)
β (°)	120.965 (2)
V (Å³)	2401.9 (3)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.35 × 0.25 × 0.25

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.975, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	9214, 2171, 1382
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.600

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.140, 1.02
No. of reflections	2171
No. of parameters	165
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	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—H14C···Cg3ⁱⁱ	0.96	2.75	3.506 (2)	136

Symmetry codes: (i) −x+1/2, y−1/2, −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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Volume 67| Part 4| April 2011| Page o1021

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