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Acta Crystallogr Sect E Struct Rep Online. 2010 January 1; 66(Pt 1): o79–o80.
Published online 2009 December 9. doi:  10.1107/S1600536809051861
PMCID: PMC2980143

6-(4-Bromo­phen­yl)-2-eth­oxy-4-(4-ethoxy­phen­yl)nicotinonitrile

Abstract

The mol­ecule of the title nicotinonitrile derivative, C22H19BrN2O2, is non-planar, the central pyridine ring making dihedral angles of 7.34 (14) and 43.56 (15)° with the 4-bromo­phenyl and 4-ethoxy­phenyl rings, respectively. The eth­oxy group of the 4-ethoxy­phenyl is slightly twisted from the attached benzene ring [C—O—C—C = 174.2 (3)°], whereas the eth­oxy group attached to the pyridine ring is in a (+)syn-clinal conformation [C—O—C—C = 83.0 (3)°]. A weak intra­molecular C—H(...)N inter­action generates an S(5) ring motif. In the crystal structure, the mol­ecules are linked by weak inter­molecular C—H(...)N inter­actions into screw chains along the b axis. These chains stacked along the a axis. π–π inter­actions with centroid–centroid distances of 3.8724 (16) and 3.8727 (16) Å are also observed.

Related literature

For bond-length data, see: Allen et al. (1987 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For the synthesis and applications of nicotinonitrile derivatives, see: Borgna et al. (1993 [triangle]); Fun et al. (2008 [triangle]); Goda et al. (2004 [triangle]); Kamal et al. (2007 [triangle]); Malinka et al. (1998 [triangle]). For related structures, see: Chantrapromma et al. (2009 [triangle]). For the stability of the temperature controller used in the data collection, see Cosier & Glazer (1986 [triangle]).

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Object name is e-66-00o79-scheme1.jpg

Experimental

Crystal data

  • C22H19BrN2O2
  • M r = 423.29
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-00o79-efi1.jpg
  • a = 4.3414 (2) Å
  • b = 14.7392 (6) Å
  • c = 29.4409 (13) Å
  • V = 1883.89 (14) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 2.20 mm−1
  • T = 100 K
  • 0.57 × 0.05 × 0.03 mm

Data collection

  • Bruker APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.368, T max = 0.931
  • 18389 measured reflections
  • 5477 independent reflections
  • 4081 reflections with I > 2σ(I)
  • R int = 0.076

Refinement

  • R[F 2 > 2σ(F 2)] = 0.039
  • wR(F 2) = 0.084
  • S = 0.99
  • 5477 reflections
  • 246 parameters
  • H-atom parameters constrained
  • Δρmax = 0.58 e Å−3
  • Δρmin = −0.54 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 2269 Friedel pairs
  • Flack parameter: 0.008 (9)

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT (Bruker, 2005 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809051861/sj2683sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809051861/sj2683Isup2.hkl

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

Acknowledgments

The authors thank the Thailand Research Fund (TRF) for a research grant (RSA 5280033) and Prince of Songkla University for financial support. AMI is grateful to the Director, NITK-Surathkal, India, for providing research facilities and the Head of the Department of Chemistry and Dean R&D, NITK-Surathkal, for their encouragement. The authors also thank the Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012.

supplementary crystallographic information

Comment

A large number of substituted pyridines have been claimed to exhibit biological activities in a number of areas (Borgna et al., 1993; Goda et al., 2004; Kamal et al., 2007; Malinka et al., 1998). The pyridine ring is among the most common heterocyclic compounds found in the naturally occurring heterocycles and in various therapeutic agents. Our research is aimed at the synthesis and preliminary pharmacological screening (in vivo) of the nicotinonitrile derivatives. Therefore the title nicotinonitrile derivative, which is a substituted pyridine compound, was synthesized by cyclization of a chalcone derivative (Fun et al., 2008) and malononitrile in order to investigate its analgesic and anti-inflammatory activities. Our results of these pharmacological studies showed that the title compound is a promising candidate for analgesic and anti-inflammatory activities. The analgesic and anti-inflammatory profiles of the title compound together with some other related nicotinonitrile derivatives will be reported elsewhere.

The title compound (I), C22H19BrN2O2 is a non-planar molecule (Fig. 1). The central pyridine ring is nearly coplanar with the 4-bromophenyl ring with the dihedral angle of 7.34 (14)° whereas it is inclined to the 4-ethoxyphenyl unit with the dihedral angle of 43.56 (15)°. The ethoxy substituent of the 4-ethoxyphenyl is slightly twisted from the mean plane of the attached benzene ring with the torsion angle C15–O2–C20–C21 = 174.2 (3)° whereas the ethoxy group attached to the pyridine ring is in a (+)syn-clinal conformation with a C11–O1–C18–C19 torsion angle of 83.0 (3)°. The orientation of the cyano group can be indicated by the torsion angle C8–C9–C10–C22 = 177.0 (3)°. A weak intramolecular C1—H1A···N1 interaction generates an S(5) ring motif (Bernstein et al., 1995). The bond distances agree with the literature values (Allen et al., 1987) and are comparable with those for a related structure (Chantrapromma et al., 2009).

In the crystal structure (Fig. 2), the molecules are linked by weak intermolecular C—H···N interactions (Table 1) into screw chains along the b axis. These chains stacked along the a axis. The crystal is further stabilized by π···π interactions with the Cg1···Cg2 distances of 3.8724 (16) Å (symmetry code: -1 + x, y, z) and 3.8727 (16) Å (symmetry code: 1 + x, y, z); Cg1 and Cg2 are the centroids of C7–C11/N1 and C1–C6 rings, respectively.

Experimental

(E-1-(4-Bromophenyl)-3-(4-ethoxyphenyl)prop-2-en-1-one (0.50 g, 0.0015 mole) were added with continuous stirring to a freshly prepared sodium alkoxide (0.0014 mole of sodium in 100 ml of ethanol). Malononitrile (1.30 g, 0.02 mol) was then added with continuous stirring at room temperature until the precipitate separated out. The resulting solid was filtered (yield 65%). Colorless needle-shaped single crystals of the title compound suitable for x-ray structure determination were recrystalized from acetone/ethanol (1:1 v/v) by the slow evaporation of the solvent at room temperature over several days, Mp. 418–419 K.

Refinement

All H atoms were positioned geometrically and allowed to ride on their parent atoms, with d(C—H) = 0.93 Å for aromatic, 0.97 for CH2 and 0.96 Å for CH3 atoms. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups. The highest residual electron density peak is located at 1.07 Å from Br1 and the deepest hole is located at 0.96 Å from Br1.

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme.
Fig. 2.
The crystal packing of the title compound viewed along the a axis, showing chains stacked down the a axis. Hydrogen bonds are shown as dashed lines.

Crystal data

C22H19BrN2O2Dx = 1.492 Mg m3
Mr = 423.29Melting point = 418–419 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 5478 reflections
a = 4.3414 (2) Åθ = 1.4–30.0°
b = 14.7392 (6) ŵ = 2.20 mm1
c = 29.4409 (13) ÅT = 100 K
V = 1883.89 (14) Å3Needle, colourless
Z = 40.57 × 0.05 × 0.03 mm
F(000) = 864

Data collection

Bruker APEXII CCD area detector diffractometer5477 independent reflections
Radiation source: sealed tube4081 reflections with I > 2σ(I)
graphiteRint = 0.076
[var phi] and ω scansθmax = 30.0°, θmin = 1.6°
Absorption correction: multi-scan (SADABS; Bruker, 2005)h = −6→6
Tmin = 0.368, Tmax = 0.931k = −20→20
18389 measured reflectionsl = −41→41

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.039H-atom parameters constrained
wR(F2) = 0.084w = 1/[σ2(Fo2) + (0.0276P)2] where P = (Fo2 + 2Fc2)/3
S = 0.99(Δ/σ)max = 0.001
5477 reflectionsΔρmax = 0.58 e Å3
246 parametersΔρmin = −0.54 e Å3
0 restraintsAbsolute structure: Flack (1983), 2269 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.008 (9)

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.
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)

xyzUiso*/Ueq
Br11.58148 (8)0.282863 (19)0.048491 (10)0.02362 (8)
O10.4205 (6)0.74788 (11)0.14589 (6)0.0216 (4)
O2−0.0548 (6)0.47728 (13)0.40035 (6)0.0252 (5)
N20.0125 (7)0.76955 (17)0.24500 (8)0.0298 (7)
N10.7019 (6)0.61534 (15)0.14495 (8)0.0196 (5)
C11.0999 (8)0.50365 (18)0.09800 (9)0.0197 (6)
H1A1.05510.56180.08770.024*
C21.2818 (8)0.44749 (19)0.07176 (10)0.0214 (7)
H2A1.36060.46790.04420.026*
C31.3459 (7)0.36055 (18)0.08677 (9)0.0191 (7)
C41.2361 (8)0.32993 (19)0.12783 (10)0.0220 (7)
H4A1.28210.27160.13770.026*
C51.0564 (8)0.38691 (17)0.15427 (9)0.0204 (6)
H5A0.98380.36650.18220.025*
C60.9818 (7)0.47489 (18)0.13976 (9)0.0185 (7)
C70.7817 (7)0.53544 (18)0.16580 (10)0.0178 (6)
C80.6704 (7)0.51430 (19)0.20904 (10)0.0195 (7)
H8A0.72620.45970.22260.023*
C90.4766 (7)0.57403 (18)0.23214 (9)0.0170 (6)
C100.3912 (8)0.65388 (18)0.20974 (9)0.0189 (6)
C110.5132 (7)0.67004 (18)0.16607 (9)0.0186 (7)
C120.3562 (8)0.55145 (19)0.27789 (9)0.0189 (7)
C130.2478 (8)0.46338 (18)0.28616 (10)0.0197 (7)
H13A0.26800.41920.26380.024*
C140.1114 (9)0.44126 (18)0.32705 (9)0.0200 (7)
H14A0.03690.38290.33180.024*
C150.0855 (9)0.50606 (18)0.36103 (9)0.0199 (6)
C160.1977 (8)0.5937 (2)0.35411 (10)0.0230 (7)
H16A0.18340.63710.37690.028*
C170.3314 (7)0.61494 (19)0.31246 (10)0.0222 (7)
H17A0.40610.67330.30770.027*
C180.5818 (8)0.7761 (2)0.10480 (8)0.0230 (6)
H18A0.79940.76260.10810.028*
H18B0.56050.84120.10120.028*
C190.4616 (8)0.7296 (2)0.06258 (9)0.0284 (7)
H19A0.55430.75640.03620.043*
H19B0.24200.73660.06100.043*
H19C0.51230.66620.06370.043*
C20−0.1371 (8)0.5444 (2)0.43323 (10)0.0243 (8)
H20A−0.26380.59110.41950.029*
H20B0.04600.57260.44580.029*
C21−0.3148 (8)0.4952 (2)0.46998 (11)0.0306 (8)
H21A−0.36480.53680.49390.046*
H21B−0.19110.44670.48190.046*
H21C−0.50110.47070.45740.046*
C220.1818 (7)0.7186 (2)0.22906 (9)0.0210 (6)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.02481 (15)0.02126 (12)0.02480 (13)0.00135 (15)−0.00071 (16)−0.00381 (13)
O10.0280 (11)0.0181 (9)0.0186 (9)0.0039 (10)0.0014 (12)0.0043 (7)
O20.0376 (14)0.0207 (9)0.0173 (9)0.0022 (11)0.0044 (11)−0.0004 (8)
N20.040 (2)0.0236 (13)0.0260 (12)0.0087 (13)−0.0018 (12)0.0006 (10)
N10.0204 (14)0.0189 (11)0.0195 (12)−0.0008 (11)−0.0024 (11)0.0008 (9)
C10.0211 (16)0.0187 (12)0.0192 (13)0.0005 (15)−0.0017 (15)0.0004 (10)
C20.0186 (16)0.0227 (15)0.0229 (15)−0.0008 (14)−0.0008 (14)0.0022 (12)
C30.0169 (18)0.0196 (13)0.0209 (14)−0.0009 (12)−0.0019 (13)−0.0023 (11)
C40.0259 (18)0.0154 (13)0.0246 (16)0.0012 (13)−0.0041 (15)0.0017 (11)
C50.0233 (17)0.0196 (13)0.0184 (13)0.0003 (15)−0.0004 (15)0.0035 (10)
C60.0169 (18)0.0186 (13)0.0199 (14)−0.0010 (12)−0.0061 (13)0.0020 (11)
C70.0172 (16)0.0152 (13)0.0210 (15)−0.0022 (12)−0.0055 (13)0.0014 (11)
C80.0186 (19)0.0190 (14)0.0208 (15)0.0006 (13)−0.0027 (13)0.0010 (12)
C90.0161 (17)0.0181 (12)0.0167 (13)−0.0037 (12)−0.0049 (12)0.0021 (10)
C100.0219 (16)0.0165 (12)0.0182 (13)0.0004 (14)−0.0045 (14)−0.0016 (10)
C110.0203 (19)0.0141 (12)0.0213 (13)−0.0008 (12)−0.0040 (12)0.0016 (10)
C120.023 (2)0.0186 (13)0.0157 (14)−0.0007 (13)−0.0018 (13)0.0008 (10)
C130.0243 (17)0.0159 (13)0.0191 (15)0.0034 (13)−0.0033 (14)−0.0017 (11)
C140.0243 (18)0.0157 (13)0.0199 (14)0.0017 (14)−0.0019 (15)0.0015 (10)
C150.0240 (16)0.0215 (13)0.0140 (13)0.0030 (16)0.0007 (15)0.0007 (10)
C160.0288 (19)0.0214 (14)0.0188 (15)0.0010 (14)−0.0027 (15)−0.0025 (12)
C170.0260 (19)0.0169 (13)0.0237 (15)−0.0011 (13)−0.0053 (14)0.0001 (11)
C180.0266 (15)0.0221 (13)0.0204 (13)−0.0010 (18)0.0012 (15)0.0036 (11)
C190.0302 (19)0.0321 (16)0.0230 (13)0.0023 (17)0.0012 (14)0.0030 (12)
C200.029 (2)0.0276 (15)0.0165 (13)0.0029 (15)0.0022 (14)−0.0077 (11)
C210.033 (2)0.0360 (18)0.0228 (16)−0.0011 (17)0.0033 (15)−0.0058 (14)
C220.0264 (17)0.0196 (12)0.0171 (13)−0.0023 (16)−0.0042 (12)0.0026 (13)

Geometric parameters (Å, °)

Br1—C31.905 (3)C10—C111.411 (4)
O1—C111.353 (3)C10—C221.435 (4)
O1—C181.458 (3)C12—C171.387 (4)
O2—C151.375 (3)C12—C131.402 (4)
O2—C201.429 (3)C13—C141.380 (4)
N2—C221.151 (4)C13—H13A0.9300
N1—C111.307 (4)C14—C151.388 (4)
N1—C71.372 (3)C14—H14A0.9300
C1—C21.380 (4)C15—C161.395 (4)
C1—C61.398 (4)C16—C171.392 (4)
C1—H1A0.9300C16—H16A0.9300
C2—C31.384 (4)C17—H17A0.9300
C2—H2A0.9300C18—C191.512 (4)
C3—C41.376 (4)C18—H18A0.9700
C4—C51.386 (4)C18—H18B0.9700
C4—H4A0.9300C19—H19A0.9600
C5—C61.403 (4)C19—H19B0.9600
C5—H5A0.9300C19—H19C0.9600
C6—C71.462 (4)C20—C211.514 (4)
C7—C81.397 (4)C20—H20A0.9700
C8—C91.395 (4)C20—H20B0.9700
C8—H8A0.9300C21—H21A0.9600
C9—C101.399 (4)C21—H21B0.9600
C9—C121.483 (4)C21—H21C0.9600
C11—O1—C18117.6 (2)C14—C13—H13A119.5
C15—O2—C20117.9 (2)C12—C13—H13A119.5
C11—N1—C7118.4 (3)C13—C14—C15120.1 (3)
C2—C1—C6121.4 (3)C13—C14—H14A120.0
C2—C1—H1A119.3C15—C14—H14A120.0
C6—C1—H1A119.3O2—C15—C14115.5 (2)
C1—C2—C3119.4 (3)O2—C15—C16124.3 (2)
C1—C2—H2A120.3C14—C15—C16120.2 (3)
C3—C2—H2A120.3C17—C16—C15118.8 (3)
C4—C3—C2121.0 (3)C17—C16—H16A120.6
C4—C3—Br1120.6 (2)C15—C16—H16A120.6
C2—C3—Br1118.4 (2)C12—C17—C16121.8 (3)
C3—C4—C5119.3 (3)C12—C17—H17A119.1
C3—C4—H4A120.3C16—C17—H17A119.1
C5—C4—H4A120.3O1—C18—C19112.8 (3)
C4—C5—C6121.3 (3)O1—C18—H18A109.0
C4—C5—H5A119.4C19—C18—H18A109.0
C6—C5—H5A119.4O1—C18—H18B109.0
C1—C6—C5117.6 (3)C19—C18—H18B109.0
C1—C6—C7119.6 (2)H18A—C18—H18B107.8
C5—C6—C7122.8 (3)C18—C19—H19A109.5
N1—C7—C8120.8 (3)C18—C19—H19B109.5
N1—C7—C6116.1 (3)H19A—C19—H19B109.5
C8—C7—C6123.2 (2)C18—C19—H19C109.5
C9—C8—C7120.8 (3)H19A—C19—H19C109.5
C9—C8—H8A119.6H19B—C19—H19C109.5
C7—C8—H8A119.6O2—C20—C21106.2 (2)
C8—C9—C10117.5 (3)O2—C20—H20A110.5
C8—C9—C12120.9 (3)C21—C20—H20A110.5
C10—C9—C12121.6 (3)O2—C20—H20B110.5
C9—C10—C11118.2 (3)C21—C20—H20B110.5
C9—C10—C22122.7 (3)H20A—C20—H20B108.7
C11—C10—C22119.1 (2)C20—C21—H21A109.5
N1—C11—O1120.1 (2)C20—C21—H21B109.5
N1—C11—C10124.4 (3)H21A—C21—H21B109.5
O1—C11—C10115.6 (2)C20—C21—H21C109.5
C17—C12—C13118.1 (3)H21A—C21—H21C109.5
C17—C12—C9122.9 (2)H21B—C21—H21C109.5
C13—C12—C9118.9 (2)N2—C22—C10179.0 (3)
C14—C13—C12120.9 (3)
C6—C1—C2—C30.8 (5)C7—N1—C11—C101.9 (4)
C1—C2—C3—C4−1.3 (5)C18—O1—C11—N1−11.6 (4)
C1—C2—C3—Br1177.1 (2)C18—O1—C11—C10168.9 (3)
C2—C3—C4—C50.6 (5)C9—C10—C11—N1−0.1 (5)
Br1—C3—C4—C5−177.8 (2)C22—C10—C11—N1−179.0 (3)
C3—C4—C5—C60.6 (5)C9—C10—C11—O1179.4 (3)
C2—C1—C6—C50.4 (5)C22—C10—C11—O10.5 (4)
C2—C1—C6—C7−178.0 (3)C8—C9—C12—C17140.0 (3)
C4—C5—C6—C1−1.1 (5)C10—C9—C12—C17−42.6 (5)
C4—C5—C6—C7177.2 (3)C8—C9—C12—C13−43.3 (4)
C11—N1—C7—C8−1.7 (4)C10—C9—C12—C13134.0 (3)
C11—N1—C7—C6177.2 (3)C17—C12—C13—C142.0 (5)
C1—C6—C7—N15.4 (4)C9—C12—C13—C14−174.8 (3)
C5—C6—C7—N1−173.0 (3)C12—C13—C14—C15−1.3 (5)
C1—C6—C7—C8−175.7 (3)C20—O2—C15—C14−169.1 (3)
C5—C6—C7—C85.9 (5)C20—O2—C15—C1610.8 (5)
N1—C7—C8—C9−0.3 (4)C13—C14—C15—O2179.8 (3)
C6—C7—C8—C9−179.1 (3)C13—C14—C15—C16−0.2 (5)
C7—C8—C9—C102.0 (4)O2—C15—C16—C17−179.1 (3)
C7—C8—C9—C12179.5 (3)C14—C15—C16—C170.9 (5)
C8—C9—C10—C11−1.9 (4)C13—C12—C17—C16−1.3 (5)
C12—C9—C10—C11−179.3 (3)C9—C12—C17—C16175.4 (3)
C8—C9—C10—C22177.0 (3)C15—C16—C17—C12−0.1 (5)
C12—C9—C10—C22−0.4 (5)C11—O1—C18—C1983.0 (3)
C7—N1—C11—O1−177.6 (3)C15—O2—C20—C21174.2 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C1—H1A···N10.932.412.758 (4)102
C5—H5A···N2i0.932.583.446 (4)156
C13—H13A···N2ii0.932.533.206 (4)130

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: SJ2683).

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