2-Phenyl­imidazo[1,2-a]pyridine-3-carbaldehyde

Anaflous, A.; Albay, H.; Benchat, N.; El Bali, B.; Dušek, M.; Fejfarová, K.

doi:10.1107/S1600536808011306

organic compounds

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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Page o927

doi:10.1107/S1600536808011306

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2-Phenylimidazo[1,2-a]pyridine-3-carbaldehyde

Abderrahman Anaflous,^a Hanane Albay,^a Nour-eddine Benchat,^a Brahim El Bali,^b Michal Dušek ^c and Karla Fejfarová ^c ^*

^aDépartement de Chimie, Faculté des Sciences, BP 717, 60000 Oujda, Morocco, ^bLaboratory of Mineral Solid and Analytical Chemistry, `LMSAC', Department of Chemistry, Faculty of Sciences, University Mohamed I, PO Box 717, 60000 Oujda, Morocco, and ^cInstitute of Physics, Na Slovance 2, 182 21 Praha 8, Czech Republic
^*Correspondence e-mail: fejfarov@fzu.cz

(Received 8 April 2008; accepted 21 April 2008; online 26 April 2008)

In the title compound, C₁₄H₁₀N₂O, the dihedral angle between the imidazo[1,2-a]pyridine and phenyl rings is 28.61 (4)° The molecules are connected into broad chains parallel to the a axis by weak C—H⋯O and C—H⋯N hydrogen bonds. The linking of the ribbons is provided by π–π stacking interactions between neighbouring pyridine rings, with a centroid–centroid distance of 3.7187 (7) Å.

Related literature

For general background, see Anaflous et al. (2008 ) and references therein. For related literature, see: Meth-Cohn & Stanforth (1991 ).

Experimental

Crystal data

C₁₄H₁₀N₂O
M_r = 222.2
Orthorhombic, P b c a
a = 13.0640 (3) Å
b = 7.4162 (2) Å
c = 21.6698 (6) Å
V = 2099.48 (9) Å³
Z = 8
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 120 K
0.57 × 0.40 × 0.24 mm

Data collection

Oxford Diffraction Xcalibur2 diffractometer with Sapphire2 CCD detector
Absorption correction: none
25795 measured reflections
2196 independent reflections
1305 reflections with I > 3σ(I)
R_int = 0.049

Refinement

R[F² > 2σ(F²)] = 0.031
wR(F²) = 0.077
S = 1.04
2196 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯N1ⁱ	0.96	2.50	3.4386 (18)	165
C6—H6⋯O1ⁱⁱ	0.96	2.46	3.1856 (16)	133
Symmetry codes: (i) -x+1, -y, -z; (ii) -x, -y, -z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SIR2002 (Burla et al., 2003 ); program(s) used to refine structure: JANA2000 (Petříček et al., 2000 ); molecular graphics: DIAMOND (Brandenburg & Putz, 2005 ); software used to prepare material for publication: JANA2000.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808011306/bg2180sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808011306/bg2180Isup2.hkl

checkCIF report

Comment top

Functionalized imidazo[1,2-a]pyridine and imidazo[1,2-a]pyrimidine systems are of great interest due to their biological activities (Anaflous et al., 2008 and reference herein).

The structure of N-(2-phenylimidazo[1,2-a]pyridin-3-yl)acetamide(I) consists of isolated molecules which packing is shown in Fig. 1. The space conformation of the molecule (Fig. 2) is characterized by the dihedral angle of 28.61 (4) ° between the imidazo[1,2-a]pyridine and the phenyl rings. Weak C—H···N and C—H···O intermolecular hydrogen bonds (Table 1) connect the molecules into chains in the a direction (Fig. 3). The connection between ribbons along b (Fig. 1) is provided by π-π stacking interactions involving neighbouring pyridine rings with centroid-centroid distance 3.7187 (7) Å.

Related literature top

For general background, see Anaflous et al. (2008) and references therein. For related literature, see: Meth-Cohn & Stanforth (1991).

Experimental top

Imidazo[1,2-a]pyridine-2-phenyl-3-carbaldehyde was synthesized according to the method described by Vilsmeier-Haack (Meth-Cohn & Stanforth, 1991) : i.e. to 1.9 g (26 mmol) of DMF cooled at 273 K, containing 4 g (26 mmol) of phosphorus oxychloride (POCl₃), was added portionwise to 10 mmole of 2-phenyl imidazo[1,2-a]pyridine. The mixture was heated at 373 K for 1 h. The solution was then neutralized at 273 K with Na₂CO₃ and extracted with Dichloromethane. The organic layer was dried over sodium sulfate and dichloromethane was removed under reduced pressure. The crude product was purified on silica gel column and imidazo[1,2-a]pyridine-2-phenyl-3-carbaldehyde was obtained in good yield (60%) as a white solid.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: JANA2000 (Petříček et al., 2000); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2000 (Petříček et al., 2000).

Figures top

	Fig. 1. Packing of of Imidazo[1,2-a]pyridine-2-phenyl-3-carbaldehyde viewed along the b axis. Hydrogen bonds are not indicated.
	Fig. 2. A molecule of the title compound, with 50% displacement ellispoids for non-H atoms.
	Fig. 3. Part of a ribbon along the a axis showing intermolecular hydrogen bonds.

2-Phenylimidazo[1,2-a]pyridine-3-carbaldehyde top

Crystal data top

C₁₄H₁₀N₂O	F(000) = 928
M_r = 222.2	D_x = 1.406 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 8746 reflections
a = 13.0640 (3) Å	θ = 2.7–26.5°
b = 7.4162 (2) Å	µ = 0.09 mm⁻¹
c = 21.6698 (6) Å	T = 120 K
V = 2099.48 (9) Å³	Prism, colourless
Z = 8	0.57 × 0.40 × 0.24 mm

Data collection top

Oxford Diffraction Xcalibur2 diffractometer with Sapphire2 CCD detector	1305 reflections with I > 3σ(I)
Radiation source: X-ray tube	R_int = 0.049
Graphite monochromator	θ_max = 26.6°, θ_min = 3.1°
Detector resolution: 8.3438 pixels mm^-1	h = −16→16
Rotation method data acquisition using ω scans	k = −9→9
25795 measured reflections	l = −27→27
2196 independent reflections

Refinement top

Refinement on F²	36 constraints
R[F² > 2σ(F²)] = 0.031	H-atom parameters constrained
wR(F²) = 0.077	Weighting scheme based on measured s.u.'s w = 1/[σ²(I) + 0.0016I²]
S = 1.04	(Δ/σ)_max = 0.007
2196 reflections	Δρ_max = 0.15 e Å⁻³
154 parameters	Δρ_min = −0.16 e Å⁻³
0 restraints

Crystal data top

C₁₄H₁₀N₂O	V = 2099.48 (9) Å³
M_r = 222.2	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 13.0640 (3) Å	µ = 0.09 mm⁻¹
b = 7.4162 (2) Å	T = 120 K
c = 21.6698 (6) Å	0.57 × 0.40 × 0.24 mm

Data collection top

Oxford Diffraction Xcalibur2 diffractometer with Sapphire2 CCD detector	1305 reflections with I > 3σ(I)
25795 measured reflections	R_int = 0.049
2196 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.031	0 restraints
wR(F²) = 0.077	H-atom parameters constrained
S = 1.04	Δρ_max = 0.15 e Å⁻³
2196 reflections	Δρ_min = −0.16 e Å⁻³
154 parameters

Special details top

Refinement. The refinement was carried out against all reflections. The conventional R-factor is always based on F. The goodness of fit as well as the weighted R-factor are based on F and F² for refinement carried out on F and F², respectively. The threshold expression is used only for calculating R-factors etc. and it is not relevant to the choice of reflections for refinement.

All the H atoms were discernible in difference Fourier maps and could be refined to reasonable geometry. According to standard procedures for organic compounds the H atoms bonded to C atoms were constrained to ideal positions. The isotropic atomic displacement parameters of hydrogen atoms were evaluated as 1.2*U_eq of the parent atom.

The program used for refinement, Jana2006, uses the weighting scheme based on the experimental expectations, see _refine_ls_weighting_details, that does not force S to be one. Therefore the values of S are usually larger than the ones from the SHELX program.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N1	0.38579 (8)	0.13099 (13)	0.06669 (5)	0.0227 (3)
N2	0.22707 (8)	0.09004 (13)	0.02784 (5)	0.0204 (3)
O1	0.03531 (7)	0.19646 (11)	0.08623 (4)	0.0297 (3)
C1	0.31590 (10)	0.18666 (16)	0.10870 (6)	0.0208 (4)
C2	0.33161 (10)	0.07295 (16)	0.01765 (6)	0.0207 (4)
C3	0.21543 (10)	0.16659 (16)	0.08658 (6)	0.0204 (4)
C4	0.36597 (11)	−0.00163 (16)	−0.03801 (6)	0.0235 (4)
C5	0.29491 (10)	−0.05736 (17)	−0.08037 (7)	0.0243 (4)
C6	0.18958 (10)	−0.03859 (17)	−0.06861 (6)	0.0247 (4)
C7	0.15617 (10)	0.03543 (16)	−0.01503 (6)	0.0236 (4)
C8	0.35054 (10)	0.25310 (16)	0.16940 (6)	0.0214 (4)
C9	0.29235 (10)	0.23521 (17)	0.22302 (7)	0.0238 (4)
C10	0.32855 (11)	0.30105 (17)	0.27874 (7)	0.0274 (5)
C11	0.42372 (11)	0.38290 (17)	0.28223 (6)	0.0283 (5)
C12	0.48307 (11)	0.39863 (17)	0.22959 (6)	0.0282 (4)
C13	0.44708 (10)	0.33402 (16)	0.17344 (6)	0.0242 (4)
C14	0.11885 (10)	0.22273 (16)	0.11073 (7)	0.0245 (4)
H4	0.437543	−0.014444	−0.047038	0.0282*
H5	0.318903	−0.109503	−0.118246	0.0292*
H6	0.139117	−0.077351	−0.097954	0.0296*
H7	0.084111	0.048834	−0.007645	0.0283*
H9	0.226757	0.177012	0.221555	0.0286*
H10	0.287357	0.289867	0.315233	0.0329*
H11	0.448433	0.4285	0.320918	0.0339*
H12	0.549259	0.454408	0.232038	0.0339*
H13	0.489068	0.345338	0.137292	0.0291*
H14	0.108688	0.287015	0.148695	0.0294*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0207 (6)	0.0225 (5)	0.0249 (6)	0.0004 (5)	0.0004 (5)	0.0017 (5)
N2	0.0196 (6)	0.0177 (5)	0.0239 (6)	−0.0005 (5)	−0.0001 (5)	0.0031 (5)
O1	0.0200 (6)	0.0315 (5)	0.0376 (6)	0.0000 (4)	−0.0002 (5)	0.0024 (5)
C1	0.0221 (7)	0.0149 (7)	0.0255 (8)	0.0007 (6)	0.0019 (6)	0.0052 (6)
C2	0.0192 (7)	0.0170 (6)	0.0259 (8)	−0.0002 (6)	0.0015 (6)	0.0051 (6)
C3	0.0211 (7)	0.0179 (6)	0.0223 (7)	−0.0008 (6)	0.0022 (6)	0.0026 (6)
C4	0.0219 (8)	0.0224 (7)	0.0263 (8)	−0.0005 (6)	0.0024 (6)	0.0027 (6)
C5	0.0281 (8)	0.0201 (7)	0.0248 (8)	−0.0015 (6)	0.0020 (6)	0.0031 (6)
C6	0.0245 (8)	0.0220 (7)	0.0275 (8)	−0.0044 (6)	−0.0037 (6)	0.0023 (6)
C7	0.0194 (8)	0.0225 (7)	0.0289 (8)	−0.0025 (6)	−0.0031 (6)	0.0043 (6)
C8	0.0228 (8)	0.0155 (6)	0.0260 (8)	0.0027 (6)	−0.0010 (6)	0.0032 (5)
C9	0.0216 (8)	0.0212 (7)	0.0288 (8)	−0.0003 (6)	−0.0001 (7)	0.0034 (6)
C10	0.0313 (8)	0.0267 (7)	0.0242 (8)	0.0049 (7)	0.0017 (7)	0.0034 (6)
C11	0.0330 (8)	0.0255 (7)	0.0263 (8)	0.0053 (7)	−0.0057 (7)	−0.0006 (6)
C12	0.0266 (8)	0.0242 (7)	0.0339 (8)	−0.0021 (6)	−0.0043 (7)	0.0013 (7)
C13	0.0243 (8)	0.0222 (7)	0.0263 (8)	0.0009 (6)	0.0007 (6)	0.0032 (6)
C14	0.0262 (8)	0.0201 (7)	0.0271 (8)	0.0008 (7)	0.0032 (7)	0.0041 (6)

Geometric parameters (Å, º) top

N1—C1	1.3537 (16)	C6—H6	0.9600
N1—C2	1.3475 (16)	C7—H7	0.9600
N2—C2	1.3893 (16)	C8—C9	1.3949 (19)
N2—C3	1.4020 (17)	C8—C13	1.3994 (18)
N2—C7	1.3731 (17)	C9—C10	1.386 (2)
O1—C14	1.2293 (16)	C9—H9	0.9600
C1—C3	1.4052 (18)	C10—C11	1.3857 (19)
C1—C8	1.4758 (18)	C10—H10	0.9600
C2—C4	1.4008 (18)	C11—C12	1.3840 (19)
C3—C14	1.4279 (18)	C11—H11	0.9600
C4—C5	1.3693 (19)	C12—C13	1.3897 (19)
C4—H4	0.9600	C12—H12	0.9600
C5—C6	1.4063 (18)	C13—H13	0.9600
C5—H5	0.9600	C14—H14	0.9600
C6—C7	1.3564 (19)

C1—N1—C2	105.87 (10)	N2—C7—H7	121.20
C2—N2—C3	106.74 (10)	C6—C7—H7	120.02
C2—N2—C7	121.92 (11)	C1—C8—C9	122.93 (12)
C3—N2—C7	131.34 (11)	C1—C8—C13	118.38 (12)
N1—C1—C3	111.62 (11)	C9—C8—C13	118.67 (12)
N1—C1—C8	119.62 (11)	C8—C9—C10	120.43 (12)
C3—C1—C8	128.74 (12)	C8—C9—H9	120.11
N1—C2—N2	111.21 (11)	C10—C9—H9	119.46
N1—C2—C4	129.56 (12)	C9—C10—C11	120.53 (13)
N2—C2—C4	119.21 (11)	C9—C10—H10	119.74
N2—C3—C1	104.54 (11)	C11—C10—H10	119.73
N2—C3—C14	123.14 (12)	C10—C11—C12	119.65 (13)
C1—C3—C14	132.02 (12)	C10—C11—H11	120.24
C2—C4—C5	118.63 (12)	C12—C11—H11	120.11
C2—C4—H4	121.78	C11—C12—C13	120.19 (12)
C5—C4—H4	119.59	C11—C12—H12	119.70
C4—C5—C6	120.80 (13)	C13—C12—H12	120.11
C4—C5—H5	118.26	C8—C13—C12	120.50 (12)
C6—C5—H5	120.94	C8—C13—H13	120.09
C5—C6—C7	120.66 (12)	C12—C13—H13	119.40
C5—C6—H6	121.49	O1—C14—C3	125.44 (13)
C7—C6—H6	117.85	O1—C14—H14	109.03
N2—C7—C6	118.78 (12)	C3—C14—H14	125.53

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···N1ⁱ	0.96	2.50	3.4386 (18)	165
C6—H6···O1ⁱⁱ	0.96	2.46	3.1856 (16)	133

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

Experimental details

Crystal data
Chemical formula	C₁₄H₁₀N₂O
M_r	222.2
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	120
a, b, c (Å)	13.0640 (3), 7.4162 (2), 21.6698 (6)
V (Å³)	2099.48 (9)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.57 × 0.40 × 0.24

Data collection
Diffractometer	Oxford Diffraction Xcalibur2 diffractometer with Sapphire2 CCD detector
Absorption correction	–
No. of measured, independent and observed [I > 3σ(I)] reflections	25795, 2196, 1305
R_int	0.049
(sin θ/λ)_max (Å⁻¹)	0.629

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.031, 0.077, 1.04
No. of reflections	2196
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.16

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR2002 (Burla et al., 2003), JANA2000 (Petříček et al., 2000), DIAMOND (Brandenburg & Putz, 2005).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···N1ⁱ	0.96	2.50	3.4386 (18)	165
C6—H6···O1ⁱⁱ	0.96	2.46	3.1856 (16)	133

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

Acknowledgements

The Grant Agency of the Czech Republic is acknowledged for grant No 202/05/0757

References

Anaflous, A., Albay, H., Benchat, N., El Bali, B., Dusek, M. & Fejfarova, K. (2008). Acta Cryst. E64, o926. Web of Science CSD CrossRef IUCr Journals Google Scholar
Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Postfach 1251, D-53002 Bonn, Germany. Google Scholar
Burla, M. C., Camalli, M., Carrozzini, B., Cascarano, G. L., Giacovazzo, C., Polidori, G. & Spagna, R. (2003). J. Appl. Cryst. 36, 1103. CrossRef IUCr Journals Google Scholar
Meth-Cohn, O. & Stanforth, S. P. (1991). Comp. Org. Synth. 2, 777–794. Google Scholar
Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England. Google Scholar
Petříček, V., Dušek, M. & Palatinus, L. (2000). JANA2000. Institute of Physics, Prague, Czech Republic. Google Scholar