2-(2-Methyl­phen­yl)-4,5-diphenyl-1H-imidazole

Seethalakshmi, T.; Puratchikody, A.; Lynch, D.E.; Kaliannan, P.; Thamotharan, S.

doi:10.1107/S160053680602109X

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 62| Part 7| July 2006| Pages o2803-o2804

https://doi.org/10.1107/S160053680602109X

2-(2-Methylphenyl)-4,5-diphenyl-1H-imidazole

T. Seethalakshmi,^a A. Puratchikody,^b Daniel E. Lynch,^c P. Kaliannan ^a and S. Thamotharan ^d ^*

^aSchool of Physics, Bharathidasan University, Tiruchirappalli 620 024, India, ^bDepartment of Pharmacy, Bharathidasan University of Technology, Bharathidasan University, Tiruchirappalli 620 024, India, ^cFaculty of Health and Life Sciences, Coventry University, Coventry CV1 5FB, England, and ^dMolecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
^*Correspondence e-mail: thamu_as@yahoo.com

(Received 26 May 2006; accepted 2 June 2006; online 14 June 2006)

In the title molecule, C₂₂H₁₈N₂, all bond lengths and angles are normal. Intermolecular N—H⋯N hydrogen bonds with an N⋯N distance of 2.933 (2) Å, link the molecules into chains running along the c axis. The crystal packing is further stabilized by van der Waals forces.

Comment

Several heterocyclic compounds with aryl substituents have previously been reported to exhibit anti-inflammatory activity in animals (Almirante et al., 1965 ; Marchetti et al., 1968 ). Of the various polyaryl heterocycles, certain 4,5-diphenyl-2-substituted imidazoles exhibited anti-inflamatory activity comparable to phenylbutazone in the carrageenan rat paw edema test (Lombardino & Wiseman, 1974 ). In view of this importance, we report here the crystal structure of the title compound, (I), which is a 4,5-diphenyl-2-substituted imidazole derivative.

The bond lengths and angles in (I) (Fig. 1) are in good agreement with the literature values (Allen et al., 1987 ). The imidazole ring makes dihedral angles of 41.2 (1), 31.5 (1) and 41.7 (1)° with the C21–C26, C41–C46 and C51–C56 aromatic rings, respectively. In the solid state, intermolecular N—H⋯N hydrogen bonds (Table 1) link the molecules into C(4) chains (Bernstein et al., 1995 ) running along the c axis. The crystal packing (Fig. 2) is further stabilized by van der Waals forces.

Figure 1
View of (I)

, showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level. H atoms are represented by circles of arbitrary radii.

Figure 2
The crystal packing of (I)

, viewed along the a axis. The intermolecular N—H⋯N hydrogen bonds are shown as dashed lines. All the H atoms, except those involved in hydrogen bonding, have been omitted for clarity.

Experimental

A mixture of benzil (5.25 g, 0.025 mol), ammonium acetate (l0 g, 0.129 mol) and 2-methylbenzaldehyde (0.018 mol) in glacial acetic acid (50 ml) was heated under reflux for 1–2 h. The product was recrystallized from aqueous ethanol (yield 80%, m.p. 484–486 K).

Crystal data

C₂₂H₁₈N₂
M_r = 310.38
Monoclinic, C c
a = 10.7538 (5) Å
b = 19.3999 (9) Å
c = 8.7900 (3) Å
β = 112.886 (2)°
V = 1689.44 (13) Å³
Z = 4
D_x = 1.220 Mg m⁻³
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 120 (2) K
Rod, colourless
0.36 × 0.06 × 0.04 mm

Data collection

Nonius KappaCCD area-detector diffractometer
φ and ω scans
Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ) T_min = 0.745, T_max = 0.927 (expected range = 0.801–0.997)
10671 measured reflections
1945 independent reflections
1744 reflections with I > 2σ(I)
R_int = 0.059
θ_max = 27.5°

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.041
wR(F²) = 0.103
S = 1.06
1945 reflections
223 parameters
H atoms treated by a mixture of independent and constrained refinement
w = 1/[σ²(F_o²) + (0.0523P)² + 0.7664P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max < 0.001
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.17 e Å⁻³
Extinction correction: SHELXL97
Extinction coefficient: 0.0089 (16)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯N3ⁱ	0.88 (3)	2.07 (3)	2.933 (3)	168 (3)
Symmetry code: (i) $[x, -y, z-{\script{1\over 2}}]$ .

The position of the amine H atom was determined from a difference Fourier map and refined freely along with its isotropic displacement parameter. The methyl H atoms were constrained to an ideal geometry (C—H = 0.98 Å), with U_iso(H) = 1.5U_eq(C), but were allowed to rotate freely about the C—C bond. The remaining H atoms were placed in geometrically idealized positions (C—H = 0.95 Å) and constrained to ride on their parent atoms with U_iso(H) = 1.2U_eq(C). Owing to the absence of any significant anomalous scatterers in the molecule, the 1433 Friedel pairs were merged before the final refinement.

Data collection: COLLECT (Hooft, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2003 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053680602109X/cv2065sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053680602109X/cv2065Isup2.hkl

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

2-(2-Methylphenyl)-4,5-diphenyl-1H-imidazole top

Crystal data top

C₂₂H₁₈N₂	F(000) = 656
M_r = 310.38	D_x = 1.220 Mg m⁻³
Monoclinic, Cc	Melting point: 484 K
Hall symbol: C -2yc	Mo Kα radiation, λ = 0.71073 Å
a = 10.7538 (5) Å	Cell parameters from 1980 reflections
b = 19.3999 (9) Å	θ = 2.9–27.5°
c = 8.7900 (3) Å	µ = 0.07 mm⁻¹
β = 112.886 (2)°	T = 120 K
V = 1689.44 (13) Å³	Rod, colourless
Z = 4	0.36 × 0.06 × 0.04 mm

Data collection top

Nonius KappaCCD area-detector diffractometer	1945 independent reflections
Radiation source: Bruker Nonius FR591 rotating anode	1744 reflections with I > 2σ(I)
10 cm confocal mirrors monochromator	R_int = 0.059
Detector resolution: 9.091 pixels mm^-1	θ_max = 27.5°, θ_min = 3.3°
φ and ω scans	h = −11→13
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	k = −25→25
T_min = 0.745, T_max = 0.927	l = −11→11
10671 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.041	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.103	w = 1/[σ²(F_o²) + (0.0523P)² + 0.7664P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
1945 reflections	Δρ_max = 0.19 e Å⁻³
223 parameters	Δρ_min = −0.17 e Å⁻³
2 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0089 (16)

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

	x	y	z	U_iso*/U_eq
N1	0.7086 (2)	0.01344 (11)	0.0732 (2)	0.0210 (4)
H1	0.698 (3)	−0.0160 (15)	−0.007 (4)	0.019 (7)*
N3	0.6705 (2)	0.06587 (10)	0.2743 (2)	0.0211 (4)
C2	0.6360 (2)	0.01323 (12)	0.1697 (3)	0.0204 (5)
C4	0.7688 (2)	0.10230 (12)	0.2418 (3)	0.0204 (5)
C5	0.7926 (3)	0.07057 (12)	0.1148 (3)	0.0215 (5)
C21	0.5397 (3)	−0.04191 (13)	0.1607 (3)	0.0241 (5)
C22	0.4158 (3)	−0.02859 (15)	0.1729 (3)	0.0292 (6)
C23	0.3333 (3)	−0.08493 (16)	0.1644 (4)	0.0398 (7)
H23	0.2486	−0.0772	0.1719	0.048*
C24	0.3697 (4)	−0.15116 (17)	0.1458 (4)	0.0455 (8)
H24	0.3110	−0.1884	0.1415	0.055*
C25	0.4917 (4)	−0.16377 (14)	0.1332 (4)	0.0393 (7)
H25	0.5173	−0.2096	0.1201	0.047*
C26	0.5763 (3)	−0.10916 (14)	0.1399 (3)	0.0292 (6)
H26	0.6600	−0.1175	0.1302	0.035*
C27	0.3689 (3)	0.04324 (16)	0.1896 (4)	0.0361 (7)
H271	0.2753	0.0415	0.1807	0.054*
H272	0.3745	0.0725	0.1016	0.054*
H273	0.4265	0.0623	0.2973	0.054*
C41	0.8327 (3)	0.16304 (12)	0.3411 (3)	0.0220 (5)
C42	0.9678 (3)	0.18026 (13)	0.3771 (3)	0.0261 (5)
H42	1.0207	0.1520	0.3372	0.031*
C43	1.0247 (3)	0.23823 (14)	0.4704 (3)	0.0320 (6)
H43	1.1161	0.2496	0.4930	0.038*
C44	0.9492 (3)	0.27985 (13)	0.5311 (3)	0.0329 (6)
H44	0.9885	0.3197	0.5944	0.039*
C45	0.8167 (3)	0.26271 (14)	0.4986 (3)	0.0312 (6)
H45	0.7646	0.2909	0.5399	0.037*
C46	0.7595 (3)	0.20471 (13)	0.4064 (3)	0.0260 (6)
H46	0.6688	0.1930	0.3870	0.031*
C51	0.8762 (2)	0.08675 (13)	0.0212 (3)	0.0230 (5)
C52	0.9424 (3)	0.03489 (15)	−0.0275 (3)	0.0277 (6)
H52	0.9372	−0.0114	0.0048	0.033*
C53	1.0161 (3)	0.05019 (16)	−0.1228 (3)	0.0325 (6)
H53	1.0609	0.0145	−0.1556	0.039*
C54	1.0237 (3)	0.11818 (17)	−0.1700 (4)	0.0379 (7)
H54	1.0732	0.1289	−0.2360	0.045*
C55	0.9597 (3)	0.16969 (15)	−0.1210 (3)	0.0345 (7)
H55	0.9658	0.2160	−0.1528	0.041*
C56	0.8860 (3)	0.15480 (14)	−0.0255 (3)	0.0288 (6)
H56	0.8425	0.1908	0.0081	0.035*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0242 (11)	0.0209 (10)	0.0183 (10)	−0.0017 (8)	0.0088 (9)	−0.0005 (8)
N3	0.0226 (10)	0.0208 (9)	0.0197 (9)	−0.0028 (8)	0.0082 (8)	0.0007 (8)
C2	0.0231 (13)	0.0205 (11)	0.0174 (11)	0.0003 (10)	0.0079 (10)	0.0029 (9)
C4	0.0187 (12)	0.0208 (11)	0.0211 (11)	−0.0001 (9)	0.0072 (9)	0.0024 (9)
C5	0.0242 (13)	0.0202 (11)	0.0209 (11)	−0.0007 (10)	0.0096 (10)	0.0035 (9)
C21	0.0281 (14)	0.0246 (12)	0.0186 (11)	−0.0051 (10)	0.0081 (10)	0.0013 (10)
C22	0.0258 (14)	0.0348 (15)	0.0256 (12)	−0.0046 (11)	0.0086 (11)	0.0047 (11)
C23	0.0326 (17)	0.0443 (17)	0.0429 (17)	−0.0126 (14)	0.0152 (14)	0.0029 (14)
C24	0.045 (2)	0.0362 (16)	0.0511 (19)	−0.0205 (14)	0.0139 (16)	0.0030 (14)
C25	0.051 (2)	0.0252 (14)	0.0413 (16)	−0.0104 (13)	0.0182 (15)	−0.0013 (12)
C26	0.0356 (16)	0.0253 (13)	0.0271 (13)	−0.0044 (11)	0.0128 (12)	−0.0005 (10)
C27	0.0258 (14)	0.0404 (16)	0.0416 (16)	0.0003 (13)	0.0127 (13)	0.0006 (13)
C41	0.0257 (13)	0.0193 (11)	0.0203 (10)	−0.0003 (10)	0.0083 (10)	0.0040 (9)
C42	0.0225 (13)	0.0246 (12)	0.0282 (13)	−0.0004 (10)	0.0064 (11)	0.0020 (10)
C43	0.0265 (15)	0.0277 (14)	0.0343 (14)	−0.0045 (11)	0.0037 (12)	0.0024 (11)
C44	0.0367 (17)	0.0187 (12)	0.0320 (14)	−0.0042 (11)	0.0011 (12)	−0.0036 (11)
C45	0.0353 (16)	0.0260 (13)	0.0292 (13)	0.0028 (12)	0.0090 (12)	−0.0010 (11)
C46	0.0254 (14)	0.0252 (13)	0.0243 (11)	0.0002 (11)	0.0061 (10)	−0.0017 (10)
C51	0.0210 (13)	0.0287 (13)	0.0200 (11)	−0.0061 (11)	0.0089 (10)	−0.0013 (10)
C52	0.0237 (13)	0.0346 (14)	0.0238 (12)	−0.0061 (11)	0.0081 (10)	−0.0051 (11)
C53	0.0267 (15)	0.0464 (17)	0.0285 (13)	−0.0046 (13)	0.0150 (12)	−0.0101 (12)
C54	0.0345 (17)	0.0562 (19)	0.0308 (14)	−0.0161 (14)	0.0212 (13)	−0.0070 (14)
C55	0.0372 (16)	0.0388 (16)	0.0282 (13)	−0.0114 (13)	0.0136 (12)	0.0046 (12)
C56	0.0297 (15)	0.0290 (13)	0.0286 (13)	−0.0034 (11)	0.0123 (12)	0.0038 (11)

Geometric parameters (Å, º) top

N1—C2	1.358 (3)	C41—C46	1.398 (4)
N1—C5	1.386 (3)	C41—C42	1.401 (4)
N1—H1	0.88 (3)	C42—C43	1.386 (4)
N3—C2	1.327 (3)	C42—H42	0.9500
N3—C4	1.390 (3)	C43—C44	1.390 (4)
C2—C21	1.470 (3)	C43—H43	0.9500
C4—C5	1.383 (3)	C44—C45	1.381 (4)
C4—C41	1.468 (3)	C44—H44	0.9500
C5—C51	1.469 (3)	C45—C46	1.384 (4)
C21—C26	1.395 (4)	C45—H45	0.9500
C21—C22	1.401 (4)	C46—H46	0.9500
C22—C23	1.391 (4)	C51—C52	1.393 (4)
C22—C27	1.508 (4)	C51—C56	1.399 (3)
C23—C24	1.372 (5)	C52—C53	1.391 (4)
C23—H23	0.9500	C52—H52	0.9500
C24—C25	1.380 (5)	C53—C54	1.395 (4)
C24—H24	0.9500	C53—H53	0.9500
C25—C26	1.383 (4)	C54—C55	1.374 (4)
C25—H25	0.9500	C54—H54	0.9500
C26—H26	0.9500	C55—C56	1.391 (4)
C27—H271	0.9800	C55—H55	0.9500
C27—H272	0.9800	C56—H56	0.9500
C27—H273	0.9800

C2—N1—C5	108.2 (2)	C46—C41—C42	118.0 (2)
C2—N1—H1	124.7 (18)	C46—C41—C4	120.0 (2)
C5—N1—H1	126.9 (18)	C42—C41—C4	122.0 (2)
C2—N3—C4	106.22 (19)	C43—C42—C41	120.5 (2)
N3—C2—N1	110.9 (2)	C43—C42—H42	119.7
N3—C2—C21	126.8 (2)	C41—C42—H42	119.7
N1—C2—C21	122.2 (2)	C42—C43—C44	120.6 (3)
C5—C4—N3	109.5 (2)	C42—C43—H43	119.7
C5—C4—C41	130.3 (2)	C44—C43—H43	119.7
N3—C4—C41	120.2 (2)	C45—C44—C43	119.4 (2)
C4—C5—N1	105.3 (2)	C45—C44—H44	120.3
C4—C5—C51	134.6 (2)	C43—C44—H44	120.3
N1—C5—C51	120.0 (2)	C44—C45—C46	120.3 (3)
C26—C21—C22	120.5 (2)	C44—C45—H45	119.8
C26—C21—C2	117.3 (2)	C46—C45—H45	119.8
C22—C21—C2	122.2 (2)	C45—C46—C41	121.2 (3)
C23—C22—C21	117.2 (3)	C45—C46—H46	119.4
C23—C22—C27	120.0 (3)	C41—C46—H46	119.4
C21—C22—C27	122.8 (2)	C52—C51—C56	119.1 (2)
C24—C23—C22	122.5 (3)	C52—C51—C5	121.0 (2)
C24—C23—H23	118.8	C56—C51—C5	119.9 (2)
C22—C23—H23	118.8	C53—C52—C51	120.7 (3)
C23—C24—C25	120.0 (3)	C53—C52—H52	119.7
C23—C24—H24	120.0	C51—C52—H52	119.7
C25—C24—H24	120.0	C52—C53—C54	119.6 (3)
C24—C25—C26	119.4 (3)	C52—C53—H53	120.2
C24—C25—H25	120.3	C54—C53—H53	120.2
C26—C25—H25	120.3	C55—C54—C53	120.0 (2)
C25—C26—C21	120.5 (3)	C55—C54—H54	120.0
C25—C26—H26	119.8	C53—C54—H54	120.0
C21—C26—H26	119.8	C54—C55—C56	120.7 (3)
C22—C27—H271	109.5	C54—C55—H55	119.7
C22—C27—H272	109.5	C56—C55—H55	119.7
H271—C27—H272	109.5	C55—C56—C51	119.9 (3)
C22—C27—H273	109.5	C55—C56—H56	120.0
H271—C27—H273	109.5	C51—C56—H56	120.0
H272—C27—H273	109.5

C4—N3—C2—N1	0.9 (3)	C2—C21—C26—C25	178.9 (2)
C4—N3—C2—C21	177.1 (2)	C5—C4—C41—C46	150.7 (3)
C5—N1—C2—N3	−1.7 (3)	N3—C4—C41—C46	−31.7 (3)
C5—N1—C2—C21	−178.1 (2)	C5—C4—C41—C42	−31.0 (4)
C2—N3—C4—C5	0.2 (3)	N3—C4—C41—C42	146.6 (2)
C2—N3—C4—C41	−177.9 (2)	C46—C41—C42—C43	−2.0 (4)
N3—C4—C5—N1	−1.1 (3)	C4—C41—C42—C43	179.6 (2)
C41—C4—C5—N1	176.7 (2)	C41—C42—C43—C44	0.6 (4)
N3—C4—C5—C51	175.4 (3)	C42—C43—C44—C45	0.4 (4)
C41—C4—C5—C51	−6.8 (5)	C43—C44—C45—C46	−0.1 (4)
C2—N1—C5—C4	1.7 (3)	C44—C45—C46—C41	−1.4 (4)
C2—N1—C5—C51	−175.5 (2)	C42—C41—C46—C45	2.4 (4)
N3—C2—C21—C26	−136.8 (3)	C4—C41—C46—C45	−179.2 (2)
N1—C2—C21—C26	39.0 (3)	C4—C5—C51—C52	142.6 (3)
N3—C2—C21—C22	43.0 (4)	N1—C5—C51—C52	−41.2 (3)
N1—C2—C21—C22	−141.2 (2)	C4—C5—C51—C56	−39.7 (4)
C26—C21—C22—C23	0.4 (4)	N1—C5—C51—C56	136.4 (3)
C2—C21—C22—C23	−179.3 (2)	C56—C51—C52—C53	−0.8 (4)
C26—C21—C22—C27	−177.8 (2)	C5—C51—C52—C53	176.9 (3)
C2—C21—C22—C27	2.4 (4)	C51—C52—C53—C54	0.1 (4)
C21—C22—C23—C24	0.3 (4)	C52—C53—C54—C55	0.6 (4)
C27—C22—C23—C24	178.6 (3)	C53—C54—C55—C56	−0.5 (5)
C22—C23—C24—C25	−0.6 (5)	C54—C55—C56—C51	−0.3 (4)
C23—C24—C25—C26	0.1 (5)	C52—C51—C56—C55	0.9 (4)
C24—C25—C26—C21	0.6 (4)	C5—C51—C56—C55	−176.8 (3)
C22—C21—C26—C25	−0.9 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N3ⁱ	0.88 (3)	2.07 (3)	2.933 (3)	168 (3)

Symmetry code: (i) x, −y, z−1/2.

Acknowledgements

The authors thank the EPSRC National Crystallography Service (Southampton, England). TS thanks Professors V. Parthasarathi, School of Physics and M. Nallu, School of Chemistry, Bharathidasan University, Tiruchirappalli, for their generous help.

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