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

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ISSN: 2056-9890

2-(4-Chloro­phen­yl)imidazo[1,2-a]pyridine-3-carbaldehyde

aSchool of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022, People's Republic of China, and bJilin College of Transportation Vocation and Technology, Changchun 130012, People's Republic of China
*Correspondence e-mail: lyunhui@163.com

(Received 31 October 2009; accepted 14 November 2009; online 25 November 2009)

The asymmetric unit of the title compound, C14H9ClN2O, contains two mol­ecules with dihedral angles of 33.52 (11) and 34.58 (11)° between their benzene rings and imidazole ring systems. In the crystal, C—H⋯N and C—H⋯O inter­actions are observed. The crystal examined was found to be a racemic twin.

Related literature

For the synthesis, see: Burkholder et al. (2001[Burkholder, C., Dolbier, W. R., Medebielle, M. & Ait-Mohand, S. (2001). Tetrahedron Lett. 42, 3077-3080.]).

[Scheme 1]

Experimental

Crystal data
  • C14H9ClN2O

  • Mr = 256.68

  • Orthorhombic, P n a 21

  • a = 21.3367 (13) Å

  • b = 7.2391 (4) Å

  • c = 15.1748 (10) Å

  • V = 2343.9 (2) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 293 K

  • 0.35 × 0.29 × 0.28 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.870, Tmax = 0.894

  • 12428 measured reflections

  • 4198 independent reflections

  • 3564 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.089

  • S = 1.03

  • 4198 reflections

  • 325 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.18 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1800 Friedel pairs

  • Flack parameter: 0.40 (5)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11⋯O2i 0.93 2.54 3.442 (3) 163
C12—H12⋯N4ii 0.93 2.59 3.518 (4) 172
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2002[Bruker (2002). SMART, SAINT and SADABS. 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Related literature top

For the synthesis, see: Burkholder et al. (2001).

Experimental top

To a solution of 2.0 mmol 2-(4-chlorophenyl)H-imidazo[1,2-a]pyridine (Burkholder et al., 2001) in DMF (10 ml) was added phosphoryl trichloride (2.2 mmol) in one portion at room temperature under stirring. The mixture was heated to 353 K and stirred for 5.0 h. After the intermediate was consumed (monitored by TLC), the reaction mixture was extracted, filtered and concentrated in vacuo. The pure product was obtained through silica gel chromatography, and yellow blocks of (I) were obtained by slow evaporation of an ethyl acetate/petroleum ether (1:1) solution at room temperature.

Refinement top

All H atoms were generated geometrically and refined as riding atoms with C—H = 0.93Å and Uiso(H) = 1.2 Ueq(C).

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXL97 (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I) with displacement ellipsoids drawn at the 30% probability level for non-H atoms.
2-(4-Chlorophenyl)imidazo[1,2-a]pyridine-3-carbaldehyde top
Crystal data top
C14H9ClN2OF(000) = 1056
Mr = 256.68Dx = 1.455 Mg m3
Orthorhombic, Pna21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2nCell parameters from 4265 reflections
a = 21.3367 (13) Åθ = 1.9–26.0°
b = 7.2391 (4) ŵ = 0.31 mm1
c = 15.1748 (10) ÅT = 293 K
V = 2343.9 (2) Å3Block, yellow
Z = 80.35 × 0.29 × 0.28 mm
Data collection top
Bruker APEX CCD
diffractometer
4198 independent reflections
Radiation source: fine-focus sealed tube3564 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ω scansθmax = 26.0°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
h = 2626
Tmin = 0.870, Tmax = 0.894k = 88
12428 measured reflectionsl = 1518
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.089 w = 1/[σ2(Fo2) + (0.0461P)2 + 0.2155P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
4198 reflectionsΔρmax = 0.22 e Å3
325 parametersΔρmin = 0.18 e Å3
1 restraintAbsolute structure: Flack (1983), 1800 Friedel pairs
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.40 (5)
Crystal data top
C14H9ClN2OV = 2343.9 (2) Å3
Mr = 256.68Z = 8
Orthorhombic, Pna21Mo Kα radiation
a = 21.3367 (13) ŵ = 0.31 mm1
b = 7.2391 (4) ÅT = 293 K
c = 15.1748 (10) Å0.35 × 0.29 × 0.28 mm
Data collection top
Bruker APEX CCD
diffractometer
4198 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2002)
3564 reflections with I > 2σ(I)
Tmin = 0.870, Tmax = 0.894Rint = 0.026
12428 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.036H-atom parameters constrained
wR(F2) = 0.089Δρmax = 0.22 e Å3
S = 1.03Δρmin = 0.18 e Å3
4198 reflectionsAbsolute structure: Flack (1983), 1800 Friedel pairs
325 parametersAbsolute structure parameter: 0.40 (5)
1 restraint
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl10.38891 (3)0.69710 (12)0.18830 (6)0.0741 (3)
Cl20.86516 (3)1.12252 (11)0.50704 (6)0.0673 (2)
O20.48266 (8)1.0458 (3)0.48167 (13)0.0652 (6)
O10.76678 (8)0.5045 (3)0.22142 (13)0.0620 (5)
N10.73924 (8)0.6319 (3)0.39935 (13)0.0373 (4)
N20.64367 (8)0.7006 (3)0.45277 (14)0.0434 (5)
N40.60866 (9)1.2130 (3)0.24891 (14)0.0403 (5)
C60.57814 (10)0.6745 (3)0.32064 (17)0.0387 (6)
N30.51184 (8)1.1689 (3)0.30384 (13)0.0368 (4)
C70.63898 (10)0.6637 (3)0.36576 (16)0.0345 (5)
C210.61298 (10)1.1699 (3)0.33495 (17)0.0370 (5)
C110.83204 (12)0.6244 (4)0.48197 (19)0.0507 (7)
H110.87500.60380.48570.061*
C170.79144 (11)1.1336 (4)0.45777 (19)0.0467 (6)
C140.70483 (10)0.6813 (3)0.47280 (16)0.0400 (6)
C200.67494 (10)1.1586 (3)0.37871 (17)0.0376 (6)
C80.69729 (10)0.6195 (3)0.32942 (16)0.0360 (5)
C280.54724 (10)1.2129 (3)0.23030 (16)0.0384 (6)
C180.78521 (11)1.0860 (4)0.37049 (19)0.0489 (6)
H180.81981.04670.33820.059*
C220.55419 (10)1.1401 (3)0.37297 (16)0.0380 (5)
C190.72678 (10)1.0975 (3)0.33157 (17)0.0423 (6)
H190.72211.06380.27280.051*
C20.51455 (11)0.7437 (4)0.1929 (2)0.0505 (6)
H20.51100.78460.13500.061*
C90.71397 (11)0.5482 (3)0.24447 (17)0.0434 (6)
H90.68190.53400.20350.052*
C50.52395 (11)0.6241 (3)0.36600 (18)0.0448 (6)
H50.52680.58460.42420.054*
C240.44781 (11)1.1572 (3)0.30118 (19)0.0462 (6)
H240.42511.12740.35150.055*
C270.51591 (12)1.2473 (4)0.15048 (19)0.0492 (6)
H270.53841.27860.10010.059*
C130.73559 (11)0.7049 (4)0.55341 (19)0.0507 (7)
H130.71330.74010.60330.061*
C100.80304 (10)0.6045 (3)0.40399 (19)0.0446 (6)
H100.82570.57270.35390.054*
C260.45240 (12)1.2345 (4)0.14768 (19)0.0526 (7)
H260.43141.25540.09490.063*
C10.57237 (11)0.7353 (4)0.23404 (18)0.0439 (6)
H10.60800.77090.20320.053*
C160.74146 (11)1.1959 (4)0.5060 (2)0.0497 (6)
H160.74661.22860.56490.060*
C40.46599 (12)0.6322 (4)0.32548 (19)0.0497 (6)
H40.43000.59880.35610.060*
C230.53638 (11)1.0703 (3)0.45701 (17)0.0463 (6)
H230.56831.04100.49630.056*
C150.68309 (11)1.2097 (4)0.46614 (18)0.0468 (6)
H150.64911.25360.49830.056*
C120.79878 (12)0.6758 (4)0.5579 (2)0.0513 (7)
H120.81970.68990.61120.062*
C250.41833 (12)1.1899 (4)0.22393 (19)0.0514 (7)
H250.37491.18270.22120.062*
C30.46229 (12)0.6899 (4)0.23968 (19)0.0485 (7)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0499 (4)0.0888 (6)0.0835 (6)0.0081 (4)0.0283 (4)0.0004 (5)
Cl20.0459 (3)0.0834 (5)0.0725 (5)0.0041 (3)0.0179 (3)0.0060 (4)
O20.0454 (10)0.0979 (15)0.0524 (12)0.0022 (10)0.0123 (9)0.0151 (11)
O10.0459 (10)0.0937 (16)0.0462 (12)0.0041 (10)0.0086 (9)0.0156 (10)
N10.0354 (10)0.0400 (11)0.0365 (12)0.0013 (8)0.0023 (9)0.0030 (8)
N20.0392 (10)0.0512 (13)0.0399 (14)0.0004 (9)0.0005 (10)0.0062 (10)
N40.0380 (10)0.0492 (12)0.0337 (12)0.0002 (9)0.0021 (9)0.0003 (9)
C60.0399 (13)0.0367 (12)0.0393 (15)0.0020 (10)0.0026 (11)0.0046 (11)
N30.0343 (10)0.0400 (10)0.0361 (12)0.0006 (8)0.0024 (9)0.0024 (8)
C70.0354 (11)0.0351 (12)0.0331 (13)0.0008 (9)0.0014 (10)0.0026 (10)
C210.0393 (12)0.0365 (12)0.0354 (14)0.0017 (10)0.0030 (11)0.0013 (10)
C110.0389 (12)0.0547 (16)0.0585 (19)0.0020 (11)0.0094 (13)0.0043 (13)
C170.0409 (13)0.0476 (15)0.0517 (18)0.0066 (11)0.0098 (13)0.0087 (12)
C140.0388 (12)0.0448 (14)0.0364 (15)0.0006 (11)0.0010 (11)0.0068 (10)
C200.0357 (12)0.0385 (13)0.0384 (15)0.0040 (9)0.0001 (10)0.0044 (11)
C80.0366 (12)0.0379 (12)0.0337 (13)0.0032 (9)0.0010 (10)0.0000 (10)
C280.0377 (12)0.0444 (14)0.0333 (14)0.0012 (10)0.0025 (10)0.0032 (10)
C180.0387 (13)0.0547 (17)0.0533 (18)0.0038 (11)0.0035 (12)0.0056 (13)
C220.0352 (12)0.0413 (13)0.0375 (14)0.0011 (9)0.0005 (11)0.0015 (10)
C190.0411 (13)0.0500 (14)0.0359 (14)0.0018 (10)0.0011 (11)0.0014 (11)
C20.0561 (15)0.0541 (17)0.0411 (16)0.0085 (12)0.0045 (14)0.0009 (13)
C90.0438 (13)0.0479 (15)0.0385 (14)0.0032 (11)0.0001 (11)0.0027 (11)
C50.0418 (13)0.0505 (15)0.0421 (15)0.0007 (10)0.0016 (11)0.0004 (12)
C240.0359 (12)0.0513 (15)0.0513 (17)0.0028 (11)0.0038 (12)0.0016 (12)
C270.0536 (15)0.0571 (16)0.0368 (16)0.0002 (12)0.0031 (13)0.0029 (12)
C130.0513 (15)0.0651 (17)0.0357 (16)0.0014 (13)0.0052 (13)0.0103 (13)
C100.0341 (12)0.0499 (15)0.0497 (16)0.0014 (11)0.0010 (11)0.0045 (12)
C260.0545 (15)0.0571 (16)0.0463 (18)0.0074 (13)0.0121 (14)0.0076 (13)
C10.0408 (13)0.0475 (15)0.0435 (17)0.0017 (11)0.0008 (11)0.0011 (11)
C160.0509 (14)0.0592 (16)0.0389 (16)0.0058 (12)0.0078 (13)0.0015 (13)
C40.0378 (13)0.0559 (16)0.0555 (18)0.0022 (11)0.0025 (12)0.0025 (13)
C230.0425 (13)0.0539 (15)0.0424 (15)0.0009 (11)0.0028 (12)0.0038 (12)
C150.0449 (13)0.0561 (17)0.0395 (17)0.0011 (11)0.0036 (12)0.0015 (12)
C120.0503 (15)0.0621 (17)0.0414 (16)0.0041 (13)0.0133 (13)0.0032 (13)
C250.0402 (13)0.0579 (17)0.0560 (18)0.0024 (12)0.0091 (13)0.0064 (13)
C30.0421 (13)0.0475 (15)0.0560 (18)0.0069 (11)0.0129 (13)0.0065 (13)
Geometric parameters (Å, º) top
Cl1—C31.750 (3)C28—C271.406 (4)
Cl2—C171.743 (2)C18—C191.382 (3)
O2—C231.219 (3)C18—H180.9300
O1—C91.221 (3)C22—C231.424 (3)
N1—C101.378 (3)C19—H190.9300
N1—C141.382 (3)C2—C31.378 (4)
N1—C81.391 (3)C2—C11.384 (3)
N2—C141.347 (3)C2—H20.9300
N2—C71.351 (3)C9—H90.9300
N4—C281.341 (3)C5—C41.382 (3)
N4—C211.346 (3)C5—H50.9300
C6—C11.391 (4)C24—C251.351 (4)
C6—C51.394 (3)C24—H240.9300
C6—C71.470 (3)C27—C261.359 (3)
N3—C241.369 (3)C27—H270.9300
N3—C281.385 (3)C13—C121.366 (3)
N3—C221.400 (3)C13—H130.9300
C7—C81.398 (3)C10—H100.9300
C21—C221.397 (3)C26—C251.404 (4)
C21—C201.482 (3)C26—H260.9300
C11—C101.343 (4)C1—H10.9300
C11—C121.403 (4)C16—C151.389 (3)
C11—H110.9300C16—H160.9300
C17—C161.370 (4)C4—C31.370 (4)
C17—C181.375 (4)C4—H40.9300
C14—C131.399 (4)C23—H230.9300
C20—C151.388 (4)C15—H150.9300
C20—C191.390 (3)C12—H120.9300
C8—C91.434 (3)C25—H250.9300
C10—N1—C14121.4 (2)C1—C2—H2120.8
C10—N1—C8131.7 (2)O1—C9—C8125.4 (2)
C14—N1—C8106.87 (18)O1—C9—H9117.3
C14—N2—C7105.8 (2)C8—C9—H9117.3
C28—N4—C21105.7 (2)C4—C5—C6120.8 (3)
C1—C6—C5118.4 (2)C4—C5—H5119.6
C1—C6—C7122.3 (2)C6—C5—H5119.6
C5—C6—C7119.2 (2)C25—C24—N3118.6 (2)
C24—N3—C28122.3 (2)C25—C24—H24120.7
C24—N3—C22131.1 (2)N3—C24—H24120.7
C28—N3—C22106.61 (18)C26—C27—C28119.3 (3)
N2—C7—C8111.4 (2)C26—C27—H27120.4
N2—C7—C6120.7 (2)C28—C27—H27120.4
C8—C7—C6127.9 (2)C12—C13—C14119.2 (2)
N4—C21—C22112.0 (2)C12—C13—H13120.4
N4—C21—C20120.6 (2)C14—C13—H13120.4
C22—C21—C20127.4 (2)C11—C10—N1119.0 (2)
C10—C11—C12121.3 (2)C11—C10—H10120.5
C10—C11—H11119.4N1—C10—H10120.5
C12—C11—H11119.4C27—C26—C25120.4 (3)
C16—C17—C18121.5 (2)C27—C26—H26119.8
C16—C17—Cl2119.2 (2)C25—C26—H26119.8
C18—C17—Cl2119.3 (2)C2—C1—C6121.2 (2)
N2—C14—N1111.1 (2)C2—C1—H1119.4
N2—C14—C13129.7 (2)C6—C1—H1119.4
N1—C14—C13119.2 (2)C17—C16—C15119.2 (3)
C15—C20—C19118.5 (2)C17—C16—H16120.4
C15—C20—C21121.7 (2)C15—C16—H16120.4
C19—C20—C21119.8 (2)C3—C4—C5119.2 (3)
N1—C8—C7104.9 (2)C3—C4—H4120.4
N1—C8—C9123.3 (2)C5—C4—H4120.4
C7—C8—C9131.1 (2)O2—C23—C22125.3 (2)
N4—C28—N3111.3 (2)O2—C23—H23117.3
N4—C28—C27130.3 (2)C22—C23—H23117.3
N3—C28—C27118.4 (2)C20—C15—C16120.7 (2)
C17—C18—C19118.9 (2)C20—C15—H15119.7
C17—C18—H18120.5C16—C15—H15119.7
C19—C18—H18120.5C13—C12—C11120.0 (3)
C21—C22—N3104.3 (2)C13—C12—H12120.0
C21—C22—C23131.6 (2)C11—C12—H12120.0
N3—C22—C23123.5 (2)C24—C25—C26121.0 (2)
C18—C19—C20121.1 (2)C24—C25—H25119.5
C18—C19—H19119.4C26—C25—H25119.5
C20—C19—H19119.4C4—C3—C2122.0 (2)
C3—C2—C1118.5 (3)C4—C3—Cl1119.0 (2)
C3—C2—H2120.8C2—C3—Cl1119.1 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O2i0.932.543.442 (3)163
C12—H12···N4ii0.932.593.518 (4)172
Symmetry codes: (i) x+1/2, y+3/2, z; (ii) x+3/2, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H9ClN2O
Mr256.68
Crystal system, space groupOrthorhombic, Pna21
Temperature (K)293
a, b, c (Å)21.3367 (13), 7.2391 (4), 15.1748 (10)
V3)2343.9 (2)
Z8
Radiation typeMo Kα
µ (mm1)0.31
Crystal size (mm)0.35 × 0.29 × 0.28
Data collection
DiffractometerBruker APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2002)
Tmin, Tmax0.870, 0.894
No. of measured, independent and
observed [I > 2σ(I)] reflections
12428, 4198, 3564
Rint0.026
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.089, 1.03
No. of reflections4198
No. of parameters325
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.18
Absolute structureFlack (1983), 1800 Friedel pairs
Absolute structure parameter0.40 (5)

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O2i0.932.543.442 (3)163
C12—H12···N4ii0.932.593.518 (4)172
Symmetry codes: (i) x+1/2, y+3/2, z; (ii) x+3/2, y1/2, z+1/2.
 

Acknowledgements

The authors thank Changchun University of Science and Technology for supporting this work.

References

First citationBruker (2002). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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