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ISSN: 2056-9890

8-Meth­­oxy-4-(4-meth­oxy­phen­yl)quinoline

aLaboratorio 223, Departamento de Química, Universidad Simón Bolívar (USB), Apartado 89000, Caracas 1080-A, Venezuela, bCentro de Química, Instituto Venezolano de Investigaciones Científicas (IVIC), Apartado 21827, Caracas 1020-A, Venezuela, and cDepartment of Chemistry, Center for Photochemical Sciences, Bowling Green State University (BGSU), Bowling Green, OH 43-403, USA.
*Correspondence e-mail: slopez@usb.ve

(Received 4 December 2009; accepted 7 December 2009; online 12 December 2009)

In the title compound, C17H15NO2, the dihedral angle between the quinoline and benzene ring systems is 62.17 (1)°. In the crystal, zigzag chains propagating in c are linked by C—H⋯O hydrogen bonds, and weak C—H⋯π inter­actions link the chains.

Related literature

The title compound was prepared as an inter­mediate for the synthesis of aluminium(III) quinolinolate complexes, which are important for their semiconductor properties and as electron-transport layer materials in organic light-emitting devices (OLEDs) (Montes et al., 2006[Montes, V. A., Pohl, R., Shinar, J. & Anzenbacher, P. Jr (2006). Chem. Eur. J. 12, 4523-4535.]). For related literature, see: Dienys et al. (1977[Dienys, G., Gureviciene, J., Cekuoliene, L. & Steponavicius, J. (1977). Liet. TSR Mokslu Akad. Darb. Ser. B, 1, 33-38.]); Muscia et al. (2006[Muscia, G. C., Bollini, M., Carnevale, J. P., Bruno, A. M. & Asis, S. E. (2006). Tetrahedron Lett. 47, 8811-8815.]); Pérez-Bolívar et al. (2006[Pérez-Bolívar, C., Montes, V. A. & Anzenbacher, P. (2006). Inorg. Chem. 45, 9610-9612.]).

[Scheme 1]

Experimental

Crystal data
  • C17H15NO2

  • Mr = 265.30

  • Monoclinic, P 21 /c

  • a = 9.362 (2) Å

  • b = 10.355 (2) Å

  • c = 14.276 (4) Å

  • β = 101.556 (6)°

  • V = 1355.9 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 295 K

  • 0.45 × 0.42 × 0.40 mm

Data collection
  • Rigaku AFC-7S Mercury diffractometer

  • Absorption correction: multi-scan (ABSCOR; Jacobson, 1998[Jacobson, R. (1998). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.940, Tmax = 0.980

  • 15093 measured reflections

  • 2785 independent reflections

  • 1868 reflections with I > 2σ(I)

  • Rint = 0.037

  • Standard reflections: 0

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.145

  • S = 1.12

  • 2785 reflections

  • 181 parameters

  • H-atom parameters constrained

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C17—H17A⋯O1i 0.96 2.55 3.322 (3) 137
C2—H2ACg2ii 0.93 2.81 3.622 (2) 146
C6—H6ACg3iii 0.93 2.80 3.592 (2) 144
C17—H17BCg2iv 0.96 2.78 3.580 (3) 142
Symmetry codes: (i) [x-1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) -x, -y, -z+1; (iv) x-1, y, z. Cg2 and Cg3 are the centroids of the C4–C9 and C10–C14 rings, respectively.

Data collection: CrystalClear (Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.])); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL and DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn,Germany.]); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The title compound (I), was prepared as a valued intermediate for the synthesis of aluminium (III) quinolinolate complexes, important for their semiconductor properties and useful properties as electron-transport layer materials in organic light-emitting devices (OLEDs) (Montes et al., 2006).

The molecular structure of (I) is shown in Figure 1 with their respective labels. All bond lenghts are in good agreement with the tabulated standard values (Table 1). In this structure quinoline motif is essentially planar (with a mean deviation 0.0213 Å), in which the maximum deviation is around atoms C1 (0.0277 Å) and C6 (0.0333 Å), respectively (see Figure 1). The methoxyphenyl substituent make a dihedral angle of 62.17 (1)° with respect to the quinoline group. Other strinking feature of (I) is that the plane defined by atoms contained for the metoxy groups C16/O1/C8/C9 and C17/O2/C13/C14 are almost co-planar with the phenyl rings with values of dihedral angle 1.73 (3) and 1.42 (2)°, respectively.

Related literature top

The title compound was prepared as an intermediate for the synthesis of aluminium(III) quinolinolate complexes, which are important for their semiconductor properties and as electron-transport layer materials in organic light-emitting devices (OLEDs) (Montes et al., 2006). For related literature, see: Dienys et al. (1977); Muscia et al. (2006); Pérez-Bolívar et al. (2006);

Experimental top

A solution of 3-dimethylamino-1-(4-methoxy-phenyl)-propan-1-one (300 mg, 1.45 mmol) and 2-methoxy-phenylamine (180 mg, 1.46 mmol) in ethanol (15 ml) was stirred at room temperature in a round bottom flask. After 15 minutes, concentrated hydrochloric acid (0.5 ml) was added dropwise and the mixture stirred under reflux for 8 h. The reaction mixture was cooled to room temperature and poured into an ice bath. The yellow solution was neutralized with a saturated solution of sodium bicarbonate to pH 7, extracted with ethyl acetate (20 ml × 3), and washed with water (20 ml × 3) and brine (10 ml × 2). The aqueous layer was extracted with dichloromethane (20 ml × 2). The organic layers were dried over anhydrous magnesium sulfate, filtered through cotton and the filtrate concentrated under vacuum to provide a reddish oil. The oil was purified by column chromatography on silica gel (mobile phase: ethyl acetate-hexane, 6:4) to afford a light-brown solid (100 mg, 26%). M.p. 146–147 °C; 1H NMR (500 MHz, CDCl3), d(p.p.m.): 3.82 (s, 3H), 4.05 (s, 3H), 6.99 (t, 3H, J= 8.5 Hz), 7.27 (d, 1H, J= 4.4 Hz), 7.34 (t, 1H, J= 8.2 Hz), 7.37 (d, 2H, J= 8.7 Hz), 7.47 (d, 1H, J= 8.6 Hz), 8.88 (d, 1H, J= 4.4 Hz). 13C NMR (126 MHz, CDCl3), d (p.p.m.): 55.29 (C17), 55.99 (C16), 107.21 (C7), 113.90 (C12 and C14), 117.59 (C5), 121.91 (C6), 126.37 (C2), 127.93 (C4), 130.48 (C9), 130.73 (C11 and C15), 140.67 (C3), 147.95 (C10), 148.68 (C1), 155.55 (C8), 159.72 (C13). IR (KBr, cm-1) 3004, 2934, 2838, 1673, 1607, 1501, 1249. EI—MS: m/z (%): 266 (100) [M+], 251 (40) [M—CH3+].

Light brown blocks of (I) were obtained by slow evaporation of dichloromethane/hexane

Refinement top

All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H distances of 0.93 (aromatic) and 0.96 Å (methyl) and with Uiso(H) = 1.5 (1.2 for aromatic H atoms) times Ueq(C).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005)); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXLTL (Sheldrick, 2008); program(s) used to refine structure: SHELXLTL (Sheldrick, 2008); molecular graphics: SHELXLTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXLTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), showing displacement elipsoids drawn at the 35% probability level and H atoms are shown as spheres of arbitrary radii.
8-Methoxy-4-(4-methoxyphenyl)quinoline top
Crystal data top
C17H15NO2F(000) = 560
Mr = 265.30Dx = 1.300 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71070 Å
Hall symbol: -P 2ybcCell parameters from 8153 reflections
a = 9.362 (2) Åθ = 4.4–55.8°
b = 10.355 (2) ŵ = 0.09 mm1
c = 14.276 (4) ÅT = 295 K
β = 101.556 (6)°Block, light brown
V = 1355.9 (5) Å30.45 × 0.42 × 0.40 mm
Z = 4
Data collection top
Rigaku AFC-7S Mercury
diffractometer
2785 independent reflections
Radiation source: Normal-focus sealed tube1868 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.037
ω scansθmax = 28.1°, θmin = 56.1°
Absorption correction: multi-scan
(ABSCOR; Jacobson, 1998)
h = 1212
Tmin = 0.940, Tmax = 0.980k = 1313
15093 measured reflectionsl = 1818
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)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.145H-atom parameters constrained
S = 1.12 w = 1/[σ2(Fo2) + (0.0538P)2 + 0.3325P]
where P = (Fo2 + 2Fc2)/3
2785 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.14 e Å3
0 restraintsΔρmin = 0.23 e Å3
Crystal data top
C17H15NO2V = 1355.9 (5) Å3
Mr = 265.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.362 (2) ŵ = 0.09 mm1
b = 10.355 (2) ÅT = 295 K
c = 14.276 (4) Å0.45 × 0.42 × 0.40 mm
β = 101.556 (6)°
Data collection top
Rigaku AFC-7S Mercury
diffractometer
2785 independent reflections
Absorption correction: multi-scan
(ABSCOR; Jacobson, 1998)
1868 reflections with I > 2σ(I)
Tmin = 0.940, Tmax = 0.980Rint = 0.037
15093 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0570 restraints
wR(F2) = 0.145H-atom parameters constrained
S = 1.12Δρmax = 0.14 e Å3
2785 reflectionsΔρmin = 0.23 e Å3
181 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
O10.42442 (15)0.09277 (15)0.26653 (10)0.0576 (4)
O20.41766 (17)0.34353 (16)0.58150 (11)0.0644 (5)
N10.22017 (18)0.27365 (17)0.23541 (12)0.0507 (5)
C10.1179 (2)0.3624 (2)0.22134 (16)0.0554 (6)
H1A0.11630.41960.17090.066*
C20.0111 (2)0.3774 (2)0.27655 (15)0.0522 (5)
H2A0.05830.44240.26180.063*
C30.0082 (2)0.29631 (19)0.35232 (14)0.0427 (5)
C40.1152 (2)0.19600 (18)0.36953 (13)0.0397 (5)
C50.1192 (2)0.10133 (19)0.44199 (14)0.0456 (5)
H5A0.05150.10420.48150.055*
C60.2215 (2)0.0066 (2)0.45375 (15)0.0493 (5)
H6A0.22170.05560.50070.059*
C70.3275 (2)0.0006 (2)0.39636 (15)0.0495 (5)
H7A0.39780.06410.40660.059*
C80.3271 (2)0.08987 (19)0.32555 (14)0.0441 (5)
C90.2189 (2)0.18964 (19)0.30946 (13)0.0414 (5)
C100.1047 (2)0.31030 (19)0.41186 (14)0.0447 (5)
C110.2518 (2)0.2989 (2)0.37074 (15)0.0504 (5)
H11A0.27880.28410.30530.060*
C120.3598 (2)0.3091 (2)0.42425 (15)0.0512 (5)
H12A0.45740.30010.39500.061*
C130.3213 (2)0.33263 (19)0.52103 (16)0.0491 (5)
C140.1750 (2)0.3464 (2)0.56353 (16)0.0554 (6)
H14A0.14870.36340.62870.066*
C150.0685 (2)0.3350 (2)0.50986 (15)0.0524 (5)
H15A0.02890.34400.53940.063*
C160.5389 (2)0.0015 (2)0.28179 (17)0.0632 (7)
H16A0.59990.01100.23590.095*
H16B0.49730.08650.27450.095*
H16C0.59620.00800.34520.095*
C170.5693 (2)0.3254 (2)0.54239 (18)0.0653 (7)
H17A0.62420.33610.59190.098*
H17B0.58470.24010.51610.098*
H17C0.60070.38790.49290.098*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0497 (8)0.0726 (10)0.0547 (9)0.0123 (7)0.0206 (7)0.0055 (8)
O20.0592 (10)0.0763 (11)0.0643 (10)0.0038 (8)0.0281 (8)0.0167 (8)
N10.0478 (10)0.0584 (11)0.0476 (10)0.0007 (9)0.0135 (8)0.0117 (9)
C10.0549 (13)0.0598 (14)0.0523 (13)0.0004 (11)0.0127 (11)0.0194 (11)
C20.0478 (12)0.0542 (13)0.0549 (13)0.0060 (10)0.0113 (10)0.0133 (10)
C30.0396 (10)0.0438 (11)0.0442 (11)0.0042 (9)0.0074 (9)0.0013 (9)
C40.0384 (10)0.0414 (11)0.0387 (10)0.0056 (8)0.0067 (8)0.0004 (8)
C50.0474 (11)0.0458 (11)0.0455 (11)0.0047 (9)0.0136 (9)0.0041 (9)
C60.0557 (12)0.0451 (11)0.0470 (11)0.0009 (10)0.0101 (10)0.0065 (10)
C70.0498 (12)0.0463 (12)0.0521 (12)0.0068 (9)0.0099 (10)0.0020 (10)
C80.0405 (11)0.0498 (12)0.0425 (11)0.0012 (9)0.0095 (9)0.0013 (9)
C90.0396 (10)0.0450 (11)0.0394 (10)0.0053 (9)0.0073 (9)0.0018 (9)
C100.0454 (11)0.0423 (11)0.0477 (12)0.0003 (9)0.0125 (9)0.0029 (9)
C110.0474 (12)0.0601 (14)0.0447 (11)0.0037 (10)0.0116 (10)0.0042 (10)
C120.0441 (11)0.0561 (13)0.0543 (13)0.0033 (10)0.0117 (10)0.0022 (10)
C130.0523 (13)0.0434 (11)0.0558 (13)0.0006 (10)0.0210 (11)0.0056 (10)
C140.0600 (14)0.0581 (14)0.0496 (12)0.0061 (11)0.0147 (11)0.0129 (10)
C150.0481 (12)0.0558 (13)0.0533 (13)0.0051 (10)0.0097 (10)0.0078 (10)
C160.0515 (13)0.0772 (17)0.0623 (14)0.0151 (12)0.0149 (11)0.0052 (13)
C170.0538 (14)0.0707 (16)0.0780 (17)0.0002 (12)0.0290 (12)0.0118 (13)
Geometric parameters (Å, º) top
O1—C81.360 (2)C7—H7A0.9300
O1—C161.434 (3)C8—C91.433 (3)
O2—C131.373 (2)C10—C111.390 (3)
O2—C171.429 (3)C10—C151.396 (3)
N1—C11.313 (3)C11—C121.388 (3)
N1—C91.371 (2)C11—H11A0.9300
C1—C21.401 (3)C12—C131.378 (3)
C1—H1A0.9300C12—H12A0.9300
C2—C31.374 (3)C13—C141.390 (3)
C2—H2A0.9300C14—C151.379 (3)
C3—C41.430 (3)C14—H14A0.9300
C3—C101.490 (3)C15—H15A0.9300
C4—C91.419 (3)C16—H16A0.9600
C4—C51.420 (3)C16—H16B0.9600
C5—C61.358 (3)C16—H16C0.9600
C5—H5A0.9300C17—H17A0.9600
C6—C71.409 (3)C17—H17B0.9600
C6—H6A0.9300C17—H17C0.9600
C7—C81.369 (3)
C8—O1—C16117.66 (17)C11—C10—C15117.36 (19)
C13—O2—C17118.02 (17)C11—C10—C3120.48 (18)
C1—N1—C9116.31 (17)C15—C10—C3122.16 (18)
N1—C1—C2124.90 (19)C12—C11—C10122.1 (2)
N1—C1—H1A117.5C12—C11—H11A119.0
C2—C1—H1A117.5C10—C11—H11A119.0
C3—C2—C1120.3 (2)C13—C12—C11119.5 (2)
C3—C2—H2A119.9C13—C12—H12A120.3
C1—C2—H2A119.9C11—C12—H12A120.3
C2—C3—C4117.12 (18)O2—C13—C12124.90 (19)
C2—C3—C10121.17 (18)O2—C13—C14115.56 (19)
C4—C3—C10121.69 (17)C12—C13—C14119.5 (2)
C9—C4—C5119.13 (17)C15—C14—C13120.5 (2)
C9—C4—C3118.05 (17)C15—C14—H14A119.7
C5—C4—C3122.80 (18)C13—C14—H14A119.7
C6—C5—C4120.22 (19)C14—C15—C10121.0 (2)
C6—C5—H5A119.9C14—C15—H15A119.5
C4—C5—H5A119.9C10—C15—H15A119.5
C5—C6—C7121.45 (19)O1—C16—H16A109.5
C5—C6—H6A119.3O1—C16—H16B109.5
C7—C6—H6A119.3H16A—C16—H16B109.5
C8—C7—C6120.08 (19)O1—C16—H16C109.5
C8—C7—H7A120.0H16A—C16—H16C109.5
C6—C7—H7A120.0H16B—C16—H16C109.5
O1—C8—C7124.69 (18)O2—C17—H17A109.5
O1—C8—C9115.14 (17)O2—C17—H17B109.5
C7—C8—C9120.16 (18)H17A—C17—H17B109.5
N1—C9—C4123.31 (18)O2—C17—H17C109.5
N1—C9—C8117.77 (17)H17A—C17—H17C109.5
C4—C9—C8118.92 (17)H17B—C17—H17C109.5
Hydrogen-bond geometry (Å, º) top
Cg2and Cg3 are the centroids of the C4–C9 and C10–C14 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C17—H17A···O1i0.962.553.322 (3)137
C2—H2A···Cg2ii0.932.813.622 (2)146
C6—H6A···Cg3iii0.932.803.592 (2)144
C17—H17B···Cg2iv0.962.783.580 (3)142
Symmetry codes: (i) x1, y+1/2, z+1/2; (ii) x, y+1/2, z+1/2; (iii) x, y, z+1; (iv) x1, y, z.

Experimental details

Crystal data
Chemical formulaC17H15NO2
Mr265.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)9.362 (2), 10.355 (2), 14.276 (4)
β (°) 101.556 (6)
V3)1355.9 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.45 × 0.42 × 0.40
Data collection
DiffractometerRigaku AFC-7S Mercury
diffractometer
Absorption correctionMulti-scan
(ABSCOR; Jacobson, 1998)
Tmin, Tmax0.940, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
15093, 2785, 1868
Rint0.037
(sin θ/λ)max1)0.662
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.145, 1.12
No. of reflections2785
No. of parameters181
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.14, 0.23

Computer programs: CrystalClear (Rigaku/MSC, 2005)), CrystalClear (Rigaku/MSC, 2005), SHELXLTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1999), SHELXLTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
Cg2and Cg3 are the centroids of the C4–C9 and C10–C14 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C17—H17A···O1i0.962.553.322 (3)137
C2—H2A···Cg2ii0.932.813.622 (2)146
C6—H6A···Cg3iii0.932.803.592 (2)144
C17—H17B···Cg2iv0.962.783.580 (3)142
Symmetry codes: (i) x1, y+1/2, z+1/2; (ii) x, y+1/2, z+1/2; (iii) x, y, z+1; (iv) x1, y, z.
 

Acknowledgements

The authors thank the Decanato de Investigación y Desarrollo (DID-USB, Caracas) and FONACIT-MCT (Project: LAB-99700821) for financial support. LL thanks the Decanato de Estudios de Postgrado (USB, Caracas) for a travel-training fellowship.

References

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