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ISSN: 2056-9890

(E)-5-(2-Thienylmethyl­ene­amino)quinolin-8-ol

aDepartment of Chemistry, University of Montreal, CP 6128, succ. Centre-ville, Montréal, Québec, Canada H3C 3J7
*Correspondence e-mail: w.skene@umontreal.ca

(Received 6 December 2007; accepted 12 December 2007; online 21 December 2007)

Two mol­ecules of the title compound, C14H10N2OS, are hydrogen bonded about a center of inversion. In the mol­ecule, the two aromatic rings are twisted by 37.27 (5)° with respect to one another. The azomethine bond is in the E configuration.

Related literature

For information about the utility of azomethines, see: Dufresne et al. (2006[Dufresne, S., Bourgeaux, M. & Skene, W. G. (2006). Acta Cryst. E62, o5602-o5604.]); Skene & Dufresne (2006[Skene, W. G. & Dufresne, S. (2006). Acta Cryst. E62, o1116-o1117.]). For related structures, see: Chen et al. (1999[Chen, X., Zhu, X., Vittal, J. J. & You, X. (1999). Acta Cryst. C55, IUC9900095.]). For an analog with an aryl ring in place of the thienyl ring, see Manecke et al. (1972[Manecke, G., Wille, W. E. & Kossmehl, G. (1972). Macromol. Chem. 160, 111-126.]).

[Scheme 1]

Experimental

Crystal data
  • C14H10N2OS

  • Mr = 254.30

  • Monoclinic, P 21 /c

  • a = 7.6798 (4) Å

  • b = 9.8592 (4) Å

  • c = 15.7512 (7) Å

  • β = 92.926 (2)°

  • V = 1191.07 (9) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 2.31 mm−1

  • T = 150 (2) K

  • 0.07 × 0.05 × 0.05 mm

Data collection
  • Bruker SMART 6K diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.855, Tmax = 0.893

  • 31904 measured reflections

  • 2377 independent reflections

  • 2152 reflections with I > 2σ(I)

  • Rint = 0.064

Refinement
  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.139

  • S = 1.11

  • 2377 reflections

  • 164 parameters

  • H-atom parameters constrained

  • Δρmax = 0.42 e Å−3

  • Δρmin = −0.62 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1⋯N1i 0.84 2.27 2.927 (2) 136
Symmetry code: (i) -x, -y, -z.

Data collection: SMART (Bruker, 2003[Bruker (2003). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997[Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and SHELXTL (Bruker, 1997[Bruker (1997). SHELXTL Version 5.10. Bruker AXS Inc., Madison, Wisconsin, USA.]); software used to prepare material for publication: UdMX (Marris, 2004[Marris, T. (2004). UdMX. Université de Montréal, Canada.]).

Supporting information


Comment top

Compound (I) was prepared as a new ligand for metal-ligand charge transfer complexes. The structure of (I) consists of quinolin-2-ol covalently linked to a thiophene unit by an azomethine bond with more stable E isomer being observed. The crystal structure has a P21/c symmetry as seen in figure 2. No solvent molecules or counter-ions were found in the crystal structure.

The bond lengths and angles of the quinolin-2-ol moiety are within 0.013 Å and 1°, respectively, to comparable structures (Chen et al., 1999). The bond lengths of the azomethine bond for C5—N2, N2—C10 and C10—C11 are 1.421 (2), 1.276 (2) and 1.446 (2) Å, respectively. The bond lengths are comparable to an all thiophene azomethine analogue (Dufresne et al., 2006) whose analogues bond lengths are 1.388 (3), 1.272 (3) and 1.441 (4) Å, respectively.

The mean planes of the two aryl moieties are twisted by 37.27 (5)° from the azomethine bond to which they are connected. This angle is smaller, i.e. 65°, (Manecke et al., 1972) than its homoaryl analogue. Steric hindrance between H6 and H10 is responsible for the twist between the mean planes similar to a thiophene azomethine, whose aryl mean planes are twisted by 33° Skene et al., 2006).

Hydrogen bonding takes place between two quinolin-8-ol moieties to form a supramolecular dimer. Figure 2 shows the two symmetry related hydrogen bonds between O1—H1···N1î^ and O1î^-H1î^···N1 that form the dimer. The length and the angle of this bond are 2.927 (2) Å and 136°, respectively. The two quinolin-2-ol involved in the hydrogen bonding are shifted by 0.593 Å.

Related literature top

For information about the utility of azomethines, see: Dufresne et al. (2006); Skene & Dufresne (2006). For related structures, see: Chen et al. (1999). For an analog with an aryl ring in place of the thienyl ring, see Manecke et al. (1972).

Experimental top

The title compound was synthesized by means of an acid catalyzed condensation of 5-amino-8-hydroxyquinoline with 2-thiophenecarboxaldehyde in ethanol with catalytic trifluoroacetic acid. The reaction was held at reflux for 20 h with stirring, cooled to room temperature and the volume reduced. Ice-cold distilled water was added to this solution causing a yellow solid to precipitate. The yellow solid was collected, washed with water and then dried under reduced pressure overnight. Crystals were obtained by slow evaporation of a concentrated solution of (1) in acetone.

Refinement top

H atoms were placed in calculated positions (C—H = 0.95 Å) and included in the refinement in the riding-model approximation, with Uiso(H) = 1.2 Ueq(C). The hydrogen on the hydroxyl group was placed in calculated position (O—H = 0.84 Å, C—O—H = 109.5°) and included in the refinement in the riding-model approximation with Uiso(H) = 1.5 Ueq(O).

Structure description top

Compound (I) was prepared as a new ligand for metal-ligand charge transfer complexes. The structure of (I) consists of quinolin-2-ol covalently linked to a thiophene unit by an azomethine bond with more stable E isomer being observed. The crystal structure has a P21/c symmetry as seen in figure 2. No solvent molecules or counter-ions were found in the crystal structure.

The bond lengths and angles of the quinolin-2-ol moiety are within 0.013 Å and 1°, respectively, to comparable structures (Chen et al., 1999). The bond lengths of the azomethine bond for C5—N2, N2—C10 and C10—C11 are 1.421 (2), 1.276 (2) and 1.446 (2) Å, respectively. The bond lengths are comparable to an all thiophene azomethine analogue (Dufresne et al., 2006) whose analogues bond lengths are 1.388 (3), 1.272 (3) and 1.441 (4) Å, respectively.

The mean planes of the two aryl moieties are twisted by 37.27 (5)° from the azomethine bond to which they are connected. This angle is smaller, i.e. 65°, (Manecke et al., 1972) than its homoaryl analogue. Steric hindrance between H6 and H10 is responsible for the twist between the mean planes similar to a thiophene azomethine, whose aryl mean planes are twisted by 33° Skene et al., 2006).

Hydrogen bonding takes place between two quinolin-8-ol moieties to form a supramolecular dimer. Figure 2 shows the two symmetry related hydrogen bonds between O1—H1···N1î^ and O1î^-H1î^···N1 that form the dimer. The length and the angle of this bond are 2.927 (2) Å and 136°, respectively. The two quinolin-2-ol involved in the hydrogen bonding are shifted by 0.593 Å.

For information about the utility of azomethines, see: Dufresne et al. (2006); Skene & Dufresne (2006). For related structures, see: Chen et al. (1999). For an analog with an aryl ring in place of the thienyl ring, see Manecke et al. (1972).

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SMART (Bruker, 2003); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997) and SHELXTL (Bruker, 1997); software used to prepare material for publication: UdMX (Marris, 2004).

Figures top
[Figure 1] Fig. 1. ORTEP representation of (I) with the numbering scheme adopted (Farrugia 1997). Ellipsoids drawn at 30% probability level.
[Figure 2] Fig. 2. The lattice structure of (I) showing hydrogen bonding. [Symmetry codes: (i) -x, -y, -z; (ii)
(E)-5-(2-Thienylmethyleneamino)quinolin-8-ol top
Crystal data top
C14H10N2OSF(000) = 528
Mr = 254.30Dx = 1.418 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybcCell parameters from 7426 reflections
a = 7.6798 (4) Åθ = 5.3–72.9°
b = 9.8592 (4) ŵ = 2.31 mm1
c = 15.7512 (7) ÅT = 150 K
β = 92.926 (2)°Block, yellow
V = 1191.07 (9) Å30.07 × 0.05 × 0.05 mm
Z = 4
Data collection top
Bruker SMART 6000
diffractometer
2377 independent reflections
Radiation source: Rotating Anode2152 reflections with I > 2σ(I)
Montel 200 optics monochromatorRint = 0.064
Detector resolution: 5.5 pixels mm-1θmax = 73.2°, θmin = 5.3°
φ and ω scansh = 99
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 1211
Tmin = 0.855, Tmax = 0.893l = 1919
31904 measured reflections
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)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.139H-atom parameters constrained
S = 1.11 w = 1/[σ2(Fo2) + (0.0968P)2 + 0.157P]
where P = (Fo2 + 2Fc2)/3
2377 reflections(Δ/σ)max < 0.001
164 parametersΔρmax = 0.42 e Å3
0 restraintsΔρmin = 0.62 e Å3
Crystal data top
C14H10N2OSV = 1191.07 (9) Å3
Mr = 254.30Z = 4
Monoclinic, P21/cCu Kα radiation
a = 7.6798 (4) ŵ = 2.31 mm1
b = 9.8592 (4) ÅT = 150 K
c = 15.7512 (7) Å0.07 × 0.05 × 0.05 mm
β = 92.926 (2)°
Data collection top
Bruker SMART 6000
diffractometer
2377 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2152 reflections with I > 2σ(I)
Tmin = 0.855, Tmax = 0.893Rint = 0.064
31904 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0540 restraints
wR(F2) = 0.139H-atom parameters constrained
S = 1.11Δρmax = 0.42 e Å3
2377 reflectionsΔρmin = 0.62 e Å3
164 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
S10.43366 (6)0.82399 (4)0.21499 (3)0.0464 (2)
O10.10263 (18)0.13156 (13)0.09352 (7)0.0446 (3)
H10.05560.07460.06230.067*
N10.0099 (2)0.14942 (15)0.07194 (9)0.0394 (3)
N20.29207 (18)0.59227 (14)0.09825 (9)0.0406 (3)
C10.0336 (3)0.16030 (18)0.15190 (11)0.0449 (4)
H1A0.09850.08860.17520.054*
C20.0107 (3)0.2718 (2)0.20431 (11)0.0460 (4)
H20.02250.27410.26160.055*
C30.1018 (2)0.37649 (19)0.17187 (11)0.0419 (4)
H30.13270.45240.20660.050*
C40.1505 (2)0.37229 (17)0.08639 (10)0.0361 (4)
C50.2413 (2)0.47908 (17)0.04695 (11)0.0373 (4)
C60.2810 (2)0.46462 (17)0.03706 (11)0.0393 (4)
H60.34220.53520.06370.047*
C70.2332 (2)0.34810 (17)0.08420 (11)0.0397 (4)
H70.26180.34140.14200.048*
C80.1456 (2)0.24404 (17)0.04735 (10)0.0367 (4)
C90.1013 (2)0.25436 (16)0.03912 (9)0.0354 (4)
C100.3002 (2)0.70894 (18)0.06355 (12)0.0424 (4)
H100.26550.71760.00500.051*
C110.3600 (2)0.82854 (16)0.10947 (12)0.0420 (4)
C120.3671 (3)0.95730 (19)0.07858 (13)0.0529 (5)
H120.33120.98090.02190.063*
C130.4333 (3)1.0526 (2)0.13929 (14)0.0554 (5)
H130.44701.14650.12770.066*
C140.4751 (3)0.99469 (18)0.21584 (12)0.0474 (4)
H140.52161.04300.26400.057*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0614 (3)0.0305 (3)0.0465 (3)0.00053 (17)0.0045 (2)0.00223 (15)
O10.0632 (8)0.0393 (7)0.0312 (6)0.0135 (6)0.0022 (5)0.0040 (5)
N10.0495 (8)0.0376 (7)0.0305 (7)0.0066 (6)0.0034 (6)0.0002 (5)
N20.0402 (7)0.0350 (8)0.0461 (8)0.0009 (6)0.0026 (6)0.0081 (6)
C10.0552 (10)0.0457 (10)0.0337 (9)0.0069 (8)0.0013 (7)0.0017 (7)
C20.0556 (10)0.0502 (10)0.0321 (8)0.0020 (8)0.0006 (7)0.0043 (7)
C30.0462 (9)0.0418 (9)0.0371 (8)0.0000 (7)0.0033 (7)0.0080 (7)
C40.0356 (8)0.0356 (8)0.0365 (8)0.0022 (7)0.0050 (6)0.0033 (6)
C50.0358 (8)0.0332 (8)0.0424 (8)0.0004 (6)0.0040 (6)0.0045 (6)
C60.0392 (8)0.0358 (9)0.0427 (9)0.0050 (6)0.0006 (6)0.0001 (6)
C70.0443 (9)0.0401 (9)0.0347 (8)0.0039 (7)0.0011 (7)0.0018 (7)
C80.0406 (8)0.0365 (8)0.0326 (8)0.0032 (7)0.0034 (6)0.0032 (6)
C90.0371 (8)0.0361 (8)0.0325 (8)0.0022 (6)0.0046 (6)0.0004 (6)
C100.0407 (9)0.0380 (9)0.0477 (10)0.0032 (7)0.0068 (7)0.0028 (7)
C110.0409 (9)0.0358 (9)0.0485 (10)0.0036 (7)0.0051 (7)0.0027 (7)
C120.0643 (12)0.0380 (10)0.0547 (11)0.0023 (9)0.0136 (9)0.0024 (8)
C130.0691 (13)0.0313 (9)0.0639 (12)0.0002 (8)0.0130 (10)0.0005 (8)
C140.0541 (10)0.0317 (9)0.0555 (11)0.0014 (8)0.0064 (8)0.0072 (7)
Geometric parameters (Å, º) top
S1—C141.7127 (18)C4—C51.423 (2)
S1—C111.7289 (19)C5—C61.380 (2)
O1—C81.358 (2)C6—C71.406 (2)
O1—H10.8400C6—H60.9500
N1—C11.324 (2)C7—C81.372 (2)
N1—C91.367 (2)C7—H70.9500
N2—C101.276 (2)C8—C91.424 (2)
N2—C51.421 (2)C10—C111.446 (2)
C1—C21.406 (3)C10—H100.9500
C1—H1A0.9500C11—C121.362 (3)
C2—C31.361 (3)C12—C131.417 (3)
C2—H20.9500C12—H120.9500
C3—C41.416 (2)C13—C141.358 (3)
C3—H30.9500C13—H130.9500
C4—C91.421 (2)C14—H140.9500
C14—S1—C1191.92 (9)C8—C7—H7119.7
C8—O1—H1109.5C6—C7—H7119.7
C1—N1—C9117.25 (14)O1—C8—C7119.70 (14)
C10—N2—C5118.84 (15)O1—C8—C9120.47 (14)
N1—C1—C2123.84 (17)C7—C8—C9119.83 (15)
N1—C1—H1A118.1N1—C9—C4123.30 (14)
C2—C1—H1A118.1N1—C9—C8117.39 (14)
C3—C2—C1119.08 (16)C4—C9—C8119.30 (15)
C3—C2—H2120.5N2—C10—C11122.82 (17)
C1—C2—H2120.5N2—C10—H10118.6
C2—C3—C4120.04 (16)C11—C10—H10118.6
C2—C3—H3120.0C12—C11—C10126.81 (18)
C4—C3—H3120.0C12—C11—S1110.52 (14)
C3—C4—C9116.48 (15)C10—C11—S1122.67 (13)
C3—C4—C5123.54 (15)C11—C12—C13113.39 (18)
C9—C4—C5119.98 (15)C11—C12—H12123.3
C6—C5—N2123.97 (15)C13—C12—H12123.3
C6—C5—C4118.63 (15)C14—C13—C12112.38 (18)
N2—C5—C4117.35 (15)C14—C13—H13123.8
C5—C6—C7121.74 (16)C12—C13—H13123.8
C5—C6—H6119.1C13—C14—S1111.78 (14)
C7—C6—H6119.1C13—C14—H14124.1
C8—C7—C6120.53 (16)S1—C14—H14124.1
C9—N1—C1—C20.8 (3)C3—C4—C9—N10.8 (2)
N1—C1—C2—C30.8 (3)C5—C4—C9—N1178.15 (15)
C1—C2—C3—C40.1 (3)C3—C4—C9—C8179.70 (15)
C2—C3—C4—C90.8 (2)C5—C4—C9—C80.7 (2)
C2—C3—C4—C5178.12 (16)O1—C8—C9—N12.1 (2)
C10—N2—C5—C633.6 (2)C7—C8—C9—N1178.23 (15)
C10—N2—C5—C4149.15 (16)O1—C8—C9—C4178.95 (14)
C3—C4—C5—C6179.47 (15)C7—C8—C9—C40.7 (2)
C9—C4—C5—C60.6 (2)C5—N2—C10—C11176.40 (16)
C3—C4—C5—N23.2 (2)N2—C10—C11—C12177.5 (2)
C9—C4—C5—N2177.93 (14)N2—C10—C11—S12.4 (3)
N2—C5—C6—C7177.58 (15)C14—S1—C11—C120.57 (17)
C4—C5—C6—C70.4 (2)C14—S1—C11—C10179.52 (17)
C5—C6—C7—C80.4 (3)C10—C11—C12—C13179.54 (19)
C6—C7—C8—O1179.12 (15)S1—C11—C12—C130.6 (2)
C6—C7—C8—C90.5 (3)C11—C12—C13—C140.2 (3)
C1—N1—C9—C40.0 (2)C12—C13—C14—S10.2 (2)
C1—N1—C9—C8178.93 (16)C11—S1—C14—C130.45 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i0.842.272.927 (2)136
Symmetry code: (i) x, y, z.

Experimental details

Crystal data
Chemical formulaC14H10N2OS
Mr254.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)150
a, b, c (Å)7.6798 (4), 9.8592 (4), 15.7512 (7)
β (°) 92.926 (2)
V3)1191.07 (9)
Z4
Radiation typeCu Kα
µ (mm1)2.31
Crystal size (mm)0.07 × 0.05 × 0.05
Data collection
DiffractometerBruker SMART 6000
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.855, 0.893
No. of measured, independent and
observed [I > 2σ(I)] reflections
31904, 2377, 2152
Rint0.064
(sin θ/λ)max1)0.621
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.139, 1.11
No. of reflections2377
No. of parameters164
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.42, 0.62

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997) and SHELXTL (Bruker, 1997), UdMX (Marris, 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i0.8402.2692.927 (2)135.5
Symmetry code: (i) x, y, z.
 

Acknowledgements

The authors acknowledge financial support from the Natural Sciences and Engineering Research Council Canada, the Centre for Self-Assembled Chemical Structures, and the Canada Foundation for Innovation. SD thanks the Université de Montréal for a graduate scholarship.

References

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First citationBruker (2004). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationChen, X., Zhu, X., Vittal, J. J. & You, X. (1999). Acta Cryst. C55, IUC9900095.  CrossRef IUCr Journals Google Scholar
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First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
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First citationMarris, T. (2004). UdMX. Université de Montréal, Canada.  Google Scholar
First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.  Google Scholar
First citationSkene, W. G. & Dufresne, S. (2006). Acta Cryst. E62, o1116–o1117.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar

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