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

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ISSN: 2056-9890

3-(Pyridin-2-yl)coumarin

aGansu Key Laboratory of Polymer Materials, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: dayuxia@nwnu.edu.cn

(Received 30 September 2010; accepted 5 October 2010; online 20 October 2010)

In the title compound, C14H9NO2, the dihedral angle between the pyridine ring and the lactone ring is 10.40 (3)°. The coumarin ring system is nearly planar, with a dihedral angle of 1.40 (2)° between the lactone and benzene rings. An intra­molecular C—H⋯O hydrogen bond occurs. In the crystal, inversion dimers linked by pairs of C—H⋯O inter­actions occur, generating R22(14) loops.

Related literature

For background to the structures and properties of coumarins, see: Fylaktakidou et al. (2004[Fylaktakidou, K. C., Hadjipavlou-Litina, D. J., Litinas, K. E. & Nicolaides, D. N. (2004). Curr. Pharm. Des. 10, 3813-3833.]); Griffiths et al. (1995[Griffiths, J., Millar, V. & Bahra, G. S. (1995). Dyes Pigm. 28, 327-339.]); Moffett (1964[Moffett, R. B. (1964). J. Med. Chem. 7, 446-449.]); Ren & Huo (2008[Ren, X. F. & Huo, S. Q. (2008). WO Patent 2008/010915 A2.]); Ren et al. (2010[Ren, X. F., Kondakova, M. E., Giesen, D. J., Rajeswaran, M., Madaras, M. & Lenhart, W. C. (2010). Inorg. Chem. 49, 1301-1303.]); Trenor et al. (2004[Trenor, S. R., Shultz, A. R., Love, B. J. & Long, T. E. (2004). Chem. Rev. 104, 3059-3077.]); Walshe et al. (1997[Walshe, M., Howarth, J., Kelly, M. T., O'Kennedy, R. & Smyth, M. R. (1997). J. Pharm. Biomed. Anal. 16, 319-325.]); Yu et al. (2006[Yu, T. Z., Zhao, Y. L. & Fan, D. W. (2006). J. Mol. Struct. 791, 18-22.]); Yu, Yang et al. (2010[Yu, T. Z., Yang, S. D., Zhao, Y. L., Zhang, H., Han, X. Q., Fan, D. W., Qiu, Y. Q. & Chen, L. L. (2010). J. Photochem. Photobiol. A, 214, 92-99.]); Yu, Zhang et al. (2010[Yu, T. Z., Zhang, P., Zhao, Y. L., Zhang, H., Meng, J., Fan, D. W., Chen, L. L. & Qiu, Y. Q. (2010). Org. Electron. 11, 41-49.]). For reference bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C14H9NO2

  • Mr = 223.22

  • Orthorhombic, P b c a

  • a = 7.1107 (3) Å

  • b = 13.9635 (5) Å

  • c = 21.2867 (9) Å

  • V = 2113.56 (15) Å3

  • Z = 8

  • Cu Kα radiation

  • μ = 0.77 mm−1

  • T = 293 K

  • 0.31 × 0.22 × 0.11 mm

Data collection
  • Siemens SMART CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.795, Tmax = 0.920

  • 4495 measured reflections

  • 2055 independent reflections

  • 1581 reflections with I > 2σ(I)

  • Rint = 0.021

Refinement
  • R[F2 > 2σ(F2)] = 0.072

  • wR(F2) = 0.230

  • S = 1.09

  • 2055 reflections

  • 154 parameters

  • H-atom parameters constrained

  • Δρmax = 0.55 e Å−3

  • Δρmin = −0.43 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11⋯O2 0.93 2.25 2.875 (3) 124
C12—H12⋯O2i 0.93 2.50 3.318 (3) 147
Symmetry code: (i) -x-1, -y, -z+1.

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments 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


Comment top

Coumarins are an important class of organic compounds, which have been extensively investigated due to their applications in biological, chemical and physical fields (Walshe, et al., 1997; Fylaktakidou, et al., 2004; Yu, et al., 2010; Trenor, et al., 2004). The photophysical and spectroscopic properties of the coumarin derivatives can be readily modified by the introduction of substituents in parent coumarin, converting themselves into more useful products and more flexibility to fit well in various applications (Griffiths, et al., 1995; Yu, et al., 2006). Among the substituted coumarins, heterocyclic groups at the 3-position have given rise to many derivatives of biological and structural importance. For example, 3-pyridyl substituted coumarins are not only known for their diverse physiological activities (Moffett, et al., 1964), but also have outstanding optical properties including high quantum yields and superior photostability (Yu, et al., 2010). In addition, 3-pyridyl substituted coumarins have attracted considerable interest due to their use as ligands for Ir (III) complexes which possess higher quantum yields and much higher brightnesses (Ren, et al., 2008; Ren, et al., 2010). In this paper, we report the synthesis and crystal structure of 3-(pyridin-2-yl)coumarin.

The molecular structure of the title compound and the ORTEP structure is shown in Fig.1. The bond lengths and angles in the molecule are within normal ranges (Allen et al., 1987). Both the pyrone and benzene rings in the coumarin motif are essentially planar. The dihedral angle between them is 1.40 (2)°, thus the coumarin moiety is essentially planar. The pyridine ring makes an angle of 10.40 (3)° with the pyrone ring, they are not coplanar.

The crystal structure is stabilized by intramolecular and intermolecular C—H···O hydrogen bonds (Fig. 2). Specially, the molecules form one-dimensional chains through intermolecular C12—H12···O2 hydrogen bonds with a motif fashion of R22(14) (Fig. 3).

Related literature top

For background to the structures and properties of coumarins, see: Fylaktakidou et al. (2004); Griffiths et al. (1995); Moffett (1964); Ren & Huo (2008); Ren et al. (2010); Trenor et al. (2004); Walshe et al. (1997); Yu et al. (2006); Yu, Yang et al. (2010); Yu, Zhang et al. (2010). For reference bond lengths, see: Allen et al. (1987).

Experimental top

Salicylaldehyde (0.1 mol) and pyridine-2-acetonitrile (0.1 mol) were dissolved in 30 ml of anhydrous alcohol, and then piperidine (0.1 ml) was added stepwise under ice bath. The mixture was stirred for 12 h at room temperature, then treated with HCl (50 ml, 3.5%) and refluxed for 10 h to hydrolyze the iminocoumarin. When the reaction was finished, the acidic solution was neutralized with aqueous ammonia until the pH was 7. The precipitate was filtered off and recrystallized from methanol to afford the title compound. m.p. 416–417 K. IR (KBr pellet, cm-1): 3042 (aryl-CH), 1723 (C=O, lactone), 1605 (C=C), 1579, 1462, 1244, 1109, 1089; 1H-NMR (500 MHz, CDCl3): 8.87 (s, 1H, H-4), 8.64 (d, 1H, J = 5.4, H-6'), 8.32 (d, 1H, J = 8.2, H-3'), 7.87–7.82 (m, 2H, Aryl-H), 7.63 (t, 1H, J = 8.4, Aryl-H), 7.42–7.34 (m, 3H, Aryl-H).

Colourless blocks of (I) were obtained by slow evaporation of the methanol solution at room temperature.

Refinement top

Non-H atoms were refined anisotropically. H atoms were treated as riding atoms with distances C—H = 0.93 Å (ArH). The isotropic displacement parameters for all H atoms were set equal to 1.2 Ueq of the carrier atom.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids for the non-hydrogen atomes drawn at the 30% probability level.
[Figure 2] Fig. 2. Intramolecular and intermolecular C—H···O hydrogen bonds.
[Figure 3] Fig. 3. Packing diagram of the title compound along a axis and b axis. H atoms are omitted for clarity.
3-(Pyridin-2-yl)coumarin top
Crystal data top
C14H9NO2Dx = 1.403 Mg m3
Mr = 223.22Melting point = 416–417 K
Orthorhombic, PbcaCu Kα radiation, λ = 1.54184 Å
a = 7.1107 (3) ÅCell parameters from 4495 reflections
b = 13.9635 (5) Åθ = 4.2–72.5°
c = 21.2867 (9) ŵ = 0.77 mm1
V = 2113.56 (15) Å3T = 293 K
Z = 8Block, colourless
F(000) = 9280.31 × 0.22 × 0.11 mm
Data collection top
Siemens SMART CCD
diffractometer
2055 independent reflections
Radiation source: fine-focus sealed tube1581 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.021
ϕ and ω scansθmax = 72.5°, θmin = 4.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 58
Tmin = 0.795, Tmax = 0.920k = 1517
4495 measured reflectionsl = 1626
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.072Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.230H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.1725P)2]
where P = (Fo2 + 2Fc2)/3
2055 reflections(Δ/σ)max < 0.001
154 parametersΔρmax = 0.55 e Å3
0 restraintsΔρmin = 0.43 e Å3
Crystal data top
C14H9NO2V = 2113.56 (15) Å3
Mr = 223.22Z = 8
Orthorhombic, PbcaCu Kα radiation
a = 7.1107 (3) ŵ = 0.77 mm1
b = 13.9635 (5) ÅT = 293 K
c = 21.2867 (9) Å0.31 × 0.22 × 0.11 mm
Data collection top
Siemens SMART CCD
diffractometer
2055 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1581 reflections with I > 2σ(I)
Tmin = 0.795, Tmax = 0.920Rint = 0.021
4495 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0720 restraints
wR(F2) = 0.230H-atom parameters constrained
S = 1.09Δρmax = 0.55 e Å3
2055 reflectionsΔρmin = 0.43 e Å3
154 parameters
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
xyzUiso*/Ueq
C10.2429 (4)0.14529 (15)0.41263 (10)0.0430 (6)
C20.3906 (4)0.20503 (18)0.42654 (12)0.0544 (7)
H20.39350.23810.46450.065*
C30.5343 (4)0.21543 (19)0.38377 (14)0.0596 (7)
H30.63460.25590.39280.072*
C40.5307 (4)0.1655 (2)0.32686 (13)0.0577 (7)
H40.62790.17300.29800.069*
C50.3826 (4)0.10503 (18)0.31356 (11)0.0505 (6)
H50.38110.07160.27580.061*
C60.2348 (3)0.09346 (15)0.35618 (10)0.0408 (5)
C70.0765 (3)0.03304 (15)0.34618 (9)0.0410 (5)
H70.07170.00300.30950.049*
C80.0669 (3)0.02542 (14)0.38726 (9)0.0393 (5)
C90.0573 (4)0.08126 (16)0.44606 (10)0.0448 (6)
C100.2310 (3)0.03764 (15)0.37410 (9)0.0396 (5)
C110.3687 (4)0.06205 (18)0.41772 (11)0.0497 (6)
H110.36340.03770.45830.060*
C120.5124 (4)0.1222 (2)0.40050 (12)0.0562 (7)
H120.60530.13860.42930.067*
C130.5179 (4)0.15823 (19)0.34010 (12)0.0541 (6)
H130.61280.19970.32730.065*
C140.3768 (4)0.13020 (18)0.29945 (11)0.0507 (6)
H140.38020.15380.25860.061*
N10.2370 (3)0.07198 (14)0.31462 (8)0.0462 (5)
O10.0984 (3)0.13797 (12)0.45491 (8)0.0503 (5)
O20.1716 (3)0.08250 (16)0.48780 (9)0.0668 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0534 (12)0.0348 (10)0.0408 (11)0.0064 (9)0.0047 (9)0.0012 (8)
C20.0652 (15)0.0419 (11)0.0562 (13)0.0006 (11)0.0111 (11)0.0058 (9)
C30.0567 (14)0.0453 (12)0.0768 (16)0.0083 (11)0.0103 (13)0.0041 (11)
C40.0518 (13)0.0560 (14)0.0652 (15)0.0017 (12)0.0045 (12)0.0062 (11)
C50.0541 (13)0.0494 (12)0.0479 (12)0.0035 (10)0.0039 (10)0.0010 (9)
C60.0469 (12)0.0361 (10)0.0394 (10)0.0070 (8)0.0045 (8)0.0012 (8)
C70.0508 (12)0.0398 (10)0.0324 (10)0.0056 (9)0.0016 (8)0.0047 (7)
C80.0490 (12)0.0364 (9)0.0325 (9)0.0065 (8)0.0011 (8)0.0021 (8)
C90.0533 (13)0.0439 (11)0.0372 (10)0.0057 (10)0.0034 (9)0.0063 (8)
C100.0483 (12)0.0365 (10)0.0341 (10)0.0059 (8)0.0010 (8)0.0021 (7)
C110.0586 (14)0.0499 (12)0.0406 (11)0.0023 (11)0.0081 (10)0.0003 (9)
C120.0564 (14)0.0587 (14)0.0535 (13)0.0035 (12)0.0129 (11)0.0070 (10)
C130.0563 (14)0.0494 (12)0.0566 (13)0.0093 (11)0.0074 (11)0.0059 (10)
C140.0626 (15)0.0479 (12)0.0416 (11)0.0051 (10)0.0051 (10)0.0017 (9)
N10.0555 (11)0.0474 (10)0.0357 (9)0.0036 (8)0.0007 (8)0.0011 (7)
O10.0630 (11)0.0465 (9)0.0415 (8)0.0009 (7)0.0000 (7)0.0119 (6)
O20.0746 (13)0.0742 (13)0.0514 (10)0.0078 (11)0.0216 (9)0.0240 (8)
Geometric parameters (Å, º) top
C1—O11.369 (3)C8—C91.476 (3)
C1—C21.374 (4)C8—C101.489 (3)
C1—C61.404 (3)C9—O21.204 (3)
C2—C31.376 (4)C9—O11.375 (3)
C2—H20.9300C10—N11.355 (3)
C3—C41.398 (4)C10—C111.392 (3)
C3—H30.9300C11—C121.373 (4)
C4—C51.379 (4)C11—H110.9300
C4—H40.9300C12—C131.381 (4)
C5—C61.398 (3)C12—H120.9300
C5—H50.9300C13—C141.382 (4)
C6—C71.423 (3)C13—H130.9300
C7—C81.347 (3)C14—N11.324 (3)
C7—H70.9300C14—H140.9300
O1—C1—C2118.5 (2)C7—C8—C10121.18 (18)
O1—C1—C6119.5 (2)C9—C8—C10120.52 (19)
C2—C1—C6121.9 (2)O2—C9—O1115.7 (2)
C1—C2—C3119.3 (2)O2—C9—C8127.0 (2)
C1—C2—H2120.4O1—C9—C8117.2 (2)
C3—C2—H2120.4N1—C10—C11121.0 (2)
C2—C3—C4120.5 (2)N1—C10—C8114.20 (19)
C2—C3—H3119.8C11—C10—C8124.82 (19)
C4—C3—H3119.8C12—C11—C10119.7 (2)
C5—C4—C3119.8 (3)C12—C11—H11120.2
C5—C4—H4120.1C10—C11—H11120.2
C3—C4—H4120.1C11—C12—C13119.5 (2)
C4—C5—C6120.8 (2)C11—C12—H12120.2
C4—C5—H5119.6C13—C12—H12120.2
C6—C5—H5119.6C12—C13—C14117.4 (2)
C5—C6—C1117.7 (2)C12—C13—H13121.3
C5—C6—C7124.5 (2)C14—C13—H13121.3
C1—C6—C7117.8 (2)N1—C14—C13124.5 (2)
C8—C7—C6123.25 (19)N1—C14—H14117.8
C8—C7—H7118.4C13—C14—H14117.8
C6—C7—H7118.4C14—N1—C10118.0 (2)
C7—C8—C9118.3 (2)C1—O1—C9123.88 (17)
O1—C1—C2—C3178.1 (2)C10—C8—C9—O1179.93 (19)
C6—C1—C2—C30.7 (4)C7—C8—C10—N110.5 (3)
C1—C2—C3—C40.3 (4)C9—C8—C10—N1169.58 (19)
C2—C3—C4—C50.3 (4)C7—C8—C10—C11168.8 (2)
C3—C4—C5—C60.5 (4)C9—C8—C10—C1111.1 (3)
C4—C5—C6—C10.1 (3)N1—C10—C11—C120.4 (4)
C4—C5—C6—C7179.7 (2)C8—C10—C11—C12178.9 (2)
O1—C1—C6—C5178.3 (2)C10—C11—C12—C130.3 (4)
C2—C1—C6—C50.5 (3)C11—C12—C13—C140.7 (4)
O1—C1—C6—C71.6 (3)C12—C13—C14—N10.4 (4)
C2—C1—C6—C7179.7 (2)C13—C14—N1—C100.2 (4)
C5—C6—C7—C8177.9 (2)C11—C10—N1—C140.7 (3)
C1—C6—C7—C81.8 (3)C8—C10—N1—C14178.7 (2)
C6—C7—C8—C91.1 (3)C2—C1—O1—C9179.5 (2)
C6—C7—C8—C10178.96 (18)C6—C1—O1—C90.7 (3)
C7—C8—C9—O2179.5 (3)O2—C9—O1—C1179.8 (2)
C10—C8—C9—O20.4 (4)C8—C9—O1—C10.1 (3)
C7—C8—C9—O10.2 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···O20.932.252.875 (3)124
C12—H12···O2i0.932.503.318 (3)147
Symmetry code: (i) x1, y, z+1.

Experimental details

Crystal data
Chemical formulaC14H9NO2
Mr223.22
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)293
a, b, c (Å)7.1107 (3), 13.9635 (5), 21.2867 (9)
V3)2113.56 (15)
Z8
Radiation typeCu Kα
µ (mm1)0.77
Crystal size (mm)0.31 × 0.22 × 0.11
Data collection
DiffractometerSiemens SMART CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.795, 0.920
No. of measured, independent and
observed [I > 2σ(I)] reflections
4495, 2055, 1581
Rint0.021
(sin θ/λ)max1)0.618
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.072, 0.230, 1.09
No. of reflections2055
No. of parameters154
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.55, 0.43

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), 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···O20.932.252.875 (3)124
C12—H12···O2i0.932.503.318 (3)147
Symmetry code: (i) x1, y, z+1.
 

Acknowledgements

This work was supported by the Natural Science Foundation of Gansu Province (3ZS061-A25–019).

References

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