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Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): o2776.
Published online 2010 October 9. doi:  10.1107/S1600536810039784
PMCID: PMC3009269

1-(3,5-Dimethyl­phen­yl)-4,5-dimethyl-2-phenyl-1H-imidazole hemihydrate

Abstract

In the title compound, C19H20N2·0.5H2O, the imidazole ring is essentially planar [maximum deviation = 0.005 (1) Å]. The imidazole ring makes dihedral angles of 67.46 (10) and 23.10 (11)° with the attached benzene and phenyl rings, respectively. The dihedral angle between the benzene and phenyl rings is 68.22 (10)°. Inter­molecular O—H(...)N and C—H(...)N hydrogen bonds are found in the crystal structure.

Related literature

For pharmacological properties of imidazole compounds, see: Lombardino & Wiseman (1974 [triangle]); For the applications of substituted imidazoles, see: Maier et al. (1989a [triangle],b [triangle]). For the synthesis of imidazoles, see: Welton (1999 [triangle]); Hermann & Kocher (1997 [triangle]). For imidazole derivatives as anti­cancer agents, see: Krezel (1998 [triangle]). For related structures and applications of imidazole derivatives, see: Gayathri et al. (2010a [triangle],b [triangle],c [triangle],d [triangle]).

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Object name is e-66-o2776-scheme1.jpg

Experimental

Crystal data

  • C19H20N2·0.5H2O
  • M r = 285.38
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2776-efi1.jpg
  • a = 16.7611 (2) Å
  • b = 11.5467 (2) Å
  • c = 16.6563 (2) Å
  • V = 3223.58 (8) Å3
  • Z = 8
  • Cu Kα radiation
  • μ = 0.55 mm−1
  • T = 123 K
  • 0.47 × 0.38 × 0.18 mm

Data collection

  • Oxford Diffraction Xcalibur Ruby Gemini diffractometer
  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010 [triangle]) T min = 0.818, T max = 1.000
  • 7791 measured reflections
  • 3193 independent reflections
  • 2630 reflections with I > 2σ(I)
  • R int = 0.020

Refinement

  • R[F 2 > 2σ(F 2)] = 0.062
  • wR(F 2) = 0.171
  • S = 1.08
  • 3193 reflections
  • 203 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.56 e Å−3
  • Δρmin = −0.33 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 [triangle]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810039784/hg2722sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810039784/hg2722Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

JJ is thankful to the Department of Science and Technology [No. SR/S1/IC-07/2007], University Grants Commission [F. No. 36–21/2008 (SR)] for providing funding for this research work. RJB acknowledges the NSF MRI program (grant No. CHE-0619278) for funds to purchase an X-ray diffractometer.

supplementary crystallographic information

Comment

Compounds with an imidazole ring system have many pharmacological properties and play important roles in biochemical processes (Lombardino & Wiseman (1974)). Many of the substituted imidazoles are known as inhibitors of fungicides and herbicides, plant growth regulators and therapeutic agents (Maier et al. (1989a,b). Recent advances in green chemistry and organometallic chemistry have extended the boundary of imidazoles to the synthesis and application of a large class of imidazoles as ionic liquids and imidazole related N-heterocyclic carbenes (Welton (1999) and Hermann & Kocher (1997)). Imidazole derivatives are also used as as potential anticancer agents (Krezel (1998)). As part of our research (Gayathri et al., (2010a,b,c,d)), we have synthesized the title compound (I) and report its crystal structure here.

In the title compound (Fig. 1), C19H20N2.H2O, the imidazole ring is essentially planar [maximum deviation of 0.005 (1) Å for N3]. The imidazole ring makes dihedral angles of 67.46 (10) and 23.10 (11)° with the benzene ring (C11—C16) attached to N1 and phenyl ring (C21—C26) attached to C2 respectively. The dihedral angle between the benzene and phenyl rings is 68.22 (10)°. Intermolecular O1W—H1W···N3 and C12—H12···N3 hydrogen bonds are found in the crystal structure (Table 1, Fig. 2).

Experimental

To pure butane-2,3-dione (1.48 g, 15 mmol) in ethanol (10 ml), 3,5-xylidine (1.8 g, 15 mmol), ammonium acetate (1.15 g, 15 mmol) and benzaldehyde (1.5 g, 15 mmol) was added about 1 h by maintaining the temperature at 333 K. The reaction mixture was refluxed for 7 days and extracted with dichloromethane. The solid separated was purified by column chromatography using hexane: ethyl acetate as the eluent. Yield: 1.91 g (46%).

Refinement

H1W attached to O1W was located in a difference Fourier map and refined freely. Another H atom attached to O1W falls on a symmetry (-x, y, 1/2 - z). Remaining H atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H = 0.95 - 0.98 Å; Uiso(H) = kUeq(C), where k = 1.5 for methyl and 1.2 for all other H atoms.

Figures

Fig. 1.
The molecular structure of the title compound, showing the atom-numbering scheme and displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius.
Fig. 2.
The packing of the title compound, viewed down the b axis. Dashed lines indicate hydrogen bonds. H atoms not involved in hydrogen bonding have been omitted.

Crystal data

C19H20N2·0.5H2ODx = 1.176 Mg m3
Mr = 285.38Melting point: 415 K
Orthorhombic, PbcnCu Kα radiation, λ = 1.54184 Å
Hall symbol: -P 2n 2abCell parameters from 5434 reflections
a = 16.7611 (2) Åθ = 5.2–28.5°
b = 11.5467 (2) ŵ = 0.55 mm1
c = 16.6563 (2) ÅT = 123 K
V = 3223.58 (8) Å3Prism, colourless
Z = 80.47 × 0.38 × 0.18 mm
F(000) = 1224

Data collection

Oxford Diffraction Xcalibur Ruby Gemini diffractometer3193 independent reflections
Radiation source: Enhance (Cu) X-ray Source2630 reflections with I > 2σ(I)
graphiteRint = 0.020
Detector resolution: 10.5081 pixels mm-1θmax = 74.2°, θmin = 5.3°
ω scansh = −20→20
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)k = −13→8
Tmin = 0.818, Tmax = 1.000l = −20→18
7791 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.062Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.171H atoms treated by a mixture of independent and constrained refinement
S = 1.08w = 1/[σ2(Fo2) + (0.0758P)2 + 2.1555P] where P = (Fo2 + 2Fc2)/3
3193 reflections(Δ/σ)max = 0.001
203 parametersΔρmax = 0.56 e Å3
0 restraintsΔρmin = −0.33 e Å3

Special details

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 > 2σ(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)

xyzUiso*/Ueq
N10.06312 (10)0.58209 (13)0.08298 (9)0.0337 (5)
N30.02135 (14)0.41115 (14)0.12586 (9)0.0486 (6)
C20.00259 (13)0.52288 (16)0.11985 (10)0.0373 (6)
C40.09630 (17)0.39935 (18)0.09289 (12)0.0478 (7)
C50.12333 (13)0.50362 (17)0.06558 (11)0.0405 (6)
C110.07375 (11)0.70592 (16)0.07891 (12)0.0320 (5)
C120.07941 (11)0.75929 (17)0.00507 (13)0.0366 (6)
C130.09222 (12)0.87905 (18)0.00254 (15)0.0457 (7)
C140.09830 (12)0.93880 (18)0.07557 (17)0.0513 (8)
C150.09275 (11)0.88545 (18)0.14936 (15)0.0437 (7)
C160.08061 (11)0.76691 (17)0.15073 (13)0.0378 (6)
C170.09981 (16)0.9395 (2)−0.07700 (17)0.0618 (9)
C180.10108 (15)0.9525 (2)0.22687 (18)0.0622 (9)
C21−0.07307 (12)0.57105 (19)0.14706 (11)0.0394 (6)
C22−0.10598 (12)0.67293 (19)0.11567 (12)0.0410 (6)
C23−0.17918 (13)0.7120 (3)0.14236 (13)0.0529 (8)
C24−0.22085 (14)0.6511 (3)0.20103 (14)0.0654 (11)
C25−0.18898 (15)0.5512 (3)0.23230 (14)0.0682 (12)
C26−0.11644 (14)0.5112 (2)0.20583 (13)0.0540 (8)
C410.1384 (2)0.2843 (2)0.09236 (15)0.0750 (12)
C510.19881 (14)0.5369 (2)0.02610 (16)0.0526 (8)
O1W0.000000.2332 (2)0.250000.126 (2)
H120.074710.71571−0.043080.0439*
H140.106661.020150.074110.0616*
H160.076960.727220.200560.0453*
H17A0.068670.89766−0.117500.0927*
H17B0.079681.01885−0.072210.0927*
H17C0.156010.94126−0.093150.0927*
H18A0.085201.033160.218030.0933*
H18B0.066720.917830.267970.0933*
H18C0.156720.949890.244850.0933*
H22−0.077820.715340.075850.0492*
H23−0.201270.780870.120530.0635*
H24−0.271100.678410.219350.0785*
H25−0.217250.509660.272460.0818*
H26−0.095300.441700.227740.0648*
H41A0.191540.293510.068790.1122*
H41B0.143400.255670.147510.1122*
H41C0.107500.228850.060440.1122*
H51A0.188150.55867−0.029750.0789*
H51B0.222450.602820.054530.0789*
H51C0.235920.471350.027310.0789*
H1W0.009 (3)0.280 (4)0.291 (3)0.138 (17)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
N10.0457 (9)0.0230 (8)0.0325 (8)−0.0005 (6)−0.0068 (7)−0.0043 (6)
N30.0938 (15)0.0256 (8)0.0263 (8)−0.0062 (9)−0.0095 (9)−0.0004 (6)
C20.0581 (12)0.0287 (10)0.0251 (8)−0.0106 (9)−0.0087 (8)−0.0003 (7)
C40.0891 (18)0.0264 (10)0.0280 (9)0.0084 (10)−0.0105 (10)−0.0056 (7)
C50.0575 (12)0.0305 (10)0.0334 (10)0.0089 (9)−0.0118 (9)−0.0095 (8)
C110.0301 (9)0.0211 (9)0.0447 (10)−0.0013 (7)−0.0033 (8)−0.0052 (7)
C120.0339 (9)0.0286 (10)0.0472 (11)0.0000 (7)0.0032 (8)−0.0027 (8)
C130.0348 (10)0.0308 (10)0.0716 (15)0.0026 (8)0.0136 (10)0.0091 (10)
C140.0373 (11)0.0228 (10)0.0939 (19)−0.0027 (8)0.0135 (11)−0.0146 (11)
C150.0325 (10)0.0304 (10)0.0682 (14)−0.0029 (8)0.0044 (9)−0.0163 (10)
C160.0318 (9)0.0329 (10)0.0486 (11)0.0011 (8)−0.0046 (8)−0.0120 (8)
C170.0595 (15)0.0423 (13)0.0835 (19)0.0066 (11)0.0225 (13)0.0217 (12)
C180.0514 (13)0.0480 (14)0.0872 (19)−0.0053 (11)0.0009 (13)−0.0374 (13)
C210.0488 (11)0.0423 (11)0.0270 (9)−0.0163 (9)−0.0087 (8)0.0002 (8)
C220.0420 (10)0.0500 (12)0.0311 (9)−0.0106 (9)−0.0029 (8)−0.0017 (9)
C230.0415 (11)0.0765 (17)0.0407 (11)−0.0037 (11)−0.0059 (9)−0.0032 (11)
C240.0373 (11)0.118 (3)0.0409 (12)−0.0158 (14)0.0000 (10)−0.0047 (14)
C250.0509 (14)0.117 (3)0.0366 (12)−0.0310 (15)−0.0069 (10)0.0178 (14)
C260.0594 (14)0.0665 (16)0.0361 (11)−0.0281 (12)−0.0119 (10)0.0113 (10)
C410.147 (3)0.0334 (12)0.0445 (13)0.0293 (16)−0.0177 (16)−0.0015 (10)
C510.0514 (13)0.0427 (12)0.0637 (14)0.0120 (10)−0.0073 (11)−0.0182 (11)
O1W0.300 (7)0.0283 (13)0.0503 (16)0.00000.041 (3)0.0000

Geometric parameters (Å, °)

O1W—H1Wi0.88 (5)C24—C251.374 (5)
O1W—H1W0.88 (5)C25—C261.373 (4)
N1—C51.387 (3)C12—H120.9500
N1—C21.369 (3)C14—H140.9500
N1—C111.443 (2)C16—H160.9500
N3—C41.378 (4)C17—H17B0.9800
N3—C21.332 (3)C17—H17A0.9800
C2—C211.457 (3)C17—H17C0.9800
C4—C411.504 (3)C18—H18C0.9800
C4—C51.365 (3)C18—H18B0.9800
C5—C511.477 (3)C18—H18A0.9800
C11—C121.379 (3)C22—H220.9500
C11—C161.393 (3)C23—H230.9500
C12—C131.400 (3)C24—H240.9500
C13—C171.503 (4)C25—H250.9500
C13—C141.402 (4)C26—H260.9500
C14—C151.378 (4)C41—H41B0.9800
C15—C181.512 (4)C41—H41C0.9800
C15—C161.384 (3)C41—H41A0.9800
C21—C221.401 (3)C51—H51C0.9800
C21—C261.402 (3)C51—H51A0.9800
C22—C231.381 (3)C51—H51B0.9800
C23—C241.392 (4)
O1W···N3i2.937 (2)C26···H16i3.0200
O1W···N32.937 (2)C41···H22ii2.9800
O1W···H262.9100C41···H51C2.9200
O1W···H26i2.9100C51···H41A2.9000
O1W···H17Aii2.9100H1W···N3i2.11 (5)
O1W···H18Aiii2.7700H1W···C4i2.96 (5)
O1W···H18Aiv2.7700H1W···H26i2.3800
O1W···H17Av2.9100H12···H17A2.4400
N3···O1W2.937 (2)H12···N3ii2.5800
N3···O1W2.937 (2)H14···H41Cxii2.4200
N3···C26i3.426 (3)H14···H17B2.4800
N3···C12ii3.388 (3)H14···H18A2.4300
N1···H222.8200H16···C22.9900
N3···H262.6100H16···H18B2.4800
N3···H1Wi2.11 (5)H16···C24i3.0500
N3···H26i2.7600H16···C25i2.9800
N3···H12ii2.5800H16···C26i3.0200
C2···C26i3.477 (3)H17A···O1Wxiii2.9100
C4···C22ii3.576 (3)H17A···H122.4400
C5···C25i3.584 (3)H17A···O1Wii2.9100
C11···C223.098 (3)H17B···C14ix3.0200
C12···N3ii3.388 (3)H17B···H142.4800
C12···C513.274 (3)H17C···C24xiv2.9400
C16···C223.362 (3)H18A···O1Wxii2.7700
C16···C213.428 (3)H18A···O1Wxv2.7700
C17···C18vi3.497 (4)H18A···H142.4300
C18···C18i3.475 (4)H18B···C15i3.0300
C18···C17vii3.497 (4)H18B···H162.4800
C21···C163.428 (3)H18B···C18i2.8400
C22···C41ii3.542 (3)H18B···H18Bi2.3200
C22···C4ii3.576 (3)H18C···C25xvi2.8600
C22···C163.362 (3)H18C···H25xvi2.2400
C22···C113.098 (3)H22···C162.9900
C25···C5i3.584 (3)H22···C41ii2.9800
C26···N3i3.426 (3)H22···N12.8200
C26···C2i3.477 (3)H22···C112.5400
C41···C22ii3.542 (3)H22···H41Cii2.4100
C51···C123.274 (3)H22···C122.9300
C2···H162.9900H25···H18Cxi2.2400
C4···H1Wi2.96 (5)H26···O1W2.9100
C4···H26i3.0300H26···C4i3.0300
C11···H51B2.7900H26···H1Wi2.3800
C11···H222.5400H26···O1W2.9100
C12···H51A3.0000H26···N3i2.7600
C12···H222.9300H26···N32.6100
C13···H51Cviii3.1000H41A···C512.9000
C14···H51Cviii2.9200H41A···H51C2.2900
C14···H17Bix3.0200H41C···H14iv2.4200
C15···H18Bi3.0300H41C···H22ii2.4100
C16···H222.9900H51A···C123.0000
C18···H18Bi2.8400H51B···C112.7900
C24···H17Cx2.9400H51C···H41A2.2900
C24···H16i3.0500H51C···C13xvii3.1000
C25···H18Cxi2.8600H51C···C14xvii2.9200
C25···H16i2.9800H51C···C412.9200
H1W—O1W—H1Wi105 (4)C13—C14—H14118.00
C2—N1—C11127.42 (16)C11—C16—H16120.00
C5—N1—C11123.22 (16)C15—C16—H16120.00
C2—N1—C5107.86 (15)C13—C17—H17B109.00
C2—N3—C4106.33 (18)C13—C17—H17C109.00
N1—C2—C21126.44 (17)C13—C17—H17A109.00
N3—C2—C21123.50 (19)H17A—C17—H17C109.00
N1—C2—N3110.03 (18)H17B—C17—H17C110.00
N3—C4—C41121.2 (2)H17A—C17—H17B109.00
C5—C4—C41128.4 (2)C15—C18—H18B109.00
N3—C4—C5110.39 (19)C15—C18—H18C109.00
N1—C5—C51123.13 (18)C15—C18—H18A109.00
C4—C5—C51131.5 (2)H18A—C18—H18C109.00
N1—C5—C4105.38 (19)H18B—C18—H18C109.00
N1—C11—C16118.10 (17)H18A—C18—H18B109.00
C12—C11—C16122.30 (18)C23—C22—H22120.00
N1—C11—C12119.56 (17)C21—C22—H22120.00
C11—C12—C13118.6 (2)C22—C23—H23120.00
C12—C13—C17119.9 (2)C24—C23—H23120.00
C14—C13—C17122.0 (2)C25—C24—H24120.00
C12—C13—C14118.1 (2)C23—C24—H24120.00
C13—C14—C15123.3 (2)C24—C25—H25120.00
C14—C15—C18121.8 (2)C26—C25—H25120.00
C16—C15—C18120.4 (2)C25—C26—H26119.00
C14—C15—C16117.8 (2)C21—C26—H26119.00
C11—C16—C15119.9 (2)C4—C41—H41A109.00
C2—C21—C22123.18 (18)C4—C41—H41B109.00
C2—C21—C26118.72 (19)H41A—C41—H41B110.00
C22—C21—C26118.08 (19)H41A—C41—H41C110.00
C21—C22—C23120.3 (2)C4—C41—H41C109.00
C22—C23—C24120.5 (3)H41B—C41—H41C109.00
C23—C24—C25119.7 (2)C5—C51—H51B109.00
C24—C25—C26120.3 (2)C5—C51—H51C109.00
C21—C26—C25121.2 (2)C5—C51—H51A109.00
C11—C12—H12121.00H51A—C51—H51C109.00
C13—C12—H12121.00H51B—C51—H51C109.00
C15—C14—H14118.00H51A—C51—H51B109.00
C5—N1—C2—N3−0.6 (2)C41—C4—C5—N1−177.7 (2)
C5—N1—C2—C21−178.74 (17)C41—C4—C5—C511.8 (4)
C11—N1—C2—N3−166.83 (17)N1—C11—C12—C13−178.02 (17)
C11—N1—C2—C2115.0 (3)C16—C11—C12—C13−0.2 (3)
C2—N1—C5—C40.1 (2)N1—C11—C16—C15178.49 (17)
C2—N1—C5—C51−179.45 (19)C12—C11—C16—C150.7 (3)
C11—N1—C5—C4167.03 (17)C11—C12—C13—C14−0.3 (3)
C11—N1—C5—C51−12.5 (3)C11—C12—C13—C17179.14 (19)
C2—N1—C11—C12−122.8 (2)C12—C13—C14—C150.4 (3)
C2—N1—C11—C1659.3 (3)C17—C13—C14—C15−179.0 (2)
C5—N1—C11—C1272.8 (2)C13—C14—C15—C160.0 (3)
C5—N1—C11—C16−105.1 (2)C13—C14—C15—C18178.9 (2)
C4—N3—C2—N10.8 (2)C14—C15—C16—C11−0.6 (3)
C4—N3—C2—C21179.07 (18)C18—C15—C16—C11−179.42 (18)
C2—N3—C4—C5−0.8 (2)C2—C21—C22—C23178.0 (2)
C2—N3—C4—C41177.5 (2)C26—C21—C22—C23−0.1 (3)
N1—C2—C21—C2222.9 (3)C2—C21—C26—C25−178.5 (2)
N1—C2—C21—C26−158.99 (19)C22—C21—C26—C25−0.3 (3)
N3—C2—C21—C22−155.0 (2)C21—C22—C23—C240.4 (4)
N3—C2—C21—C2623.1 (3)C22—C23—C24—C25−0.3 (4)
N3—C4—C5—N10.5 (2)C23—C24—C25—C26−0.1 (4)
N3—C4—C5—C51179.9 (2)C24—C25—C26—C210.4 (4)

Symmetry codes: (i) −x, y, −z+1/2; (ii) −x, −y+1, −z; (iii) −x, y−1, −z+1/2; (iv) x, y−1, z; (v) x, −y+1, z+1/2; (vi) x, −y+2, z−1/2; (vii) x, −y+2, z+1/2; (viii) −x+1/2, y+1/2, z; (ix) −x, −y+2, −z; (x) x−1/2, −y+3/2, −z; (xi) x−1/2, y−1/2, −z+1/2; (xii) x, y+1, z; (xiii) x, −y+1, z−1/2; (xiv) x+1/2, −y+3/2, −z; (xv) −x, y+1, −z+1/2; (xvi) x+1/2, y+1/2, −z+1/2; (xvii) −x+1/2, y−1/2, z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1W—H1W···N3i0.88 (5)2.11 (5)2.937 (2)155 (4)
C12—H12···N3ii0.952.583.388 (3)144

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HG2722).

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