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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 3| March 2012| Page o897
doi:10.1107/S1600536812007635

4-[(E)-(4-Methyl­phen­yl)imino­meth­yl]phenol

L. Jothi,a G. Vasuki,b* R. Ramesh Babuc and K. Ramamurthic

aDepartment of Physics, NKR Government Arts College for Women, Namakkal 1, India, bDepartment of Physics, Kunthavai Naachiar Government Arts College (W) (Autonomous), Thanjavur 7, India, and cCrystal Growth and Thin Film Laboratory, School of Physics, Bharathidasan University, Tiruchirappalli 24, India
*Correspondence e-mail: vasuki.arasi@yahoo.com

(Received 22 January 2012; accepted 20 February 2012; online 29 February 2012)

In the title compound, C14H13NO, the two rings show significant deviation from coplanarity, with a dihedral angle between the two planes of 49.40 (5)°. The hy­droxy group is involved in an inter­molecular O—H⋯N hydrogen bond, forming an extended one-dimensional zigzag chain along (001).

Related literature

For the applications of Schiff bases, see: Qian & Cui (2009[Qian, S.-S. & Cui, H.-Y. (2009). Acta Cryst. E65, o3072.]). For related structures, see: Burgess et al. (1999[Burgess, J., Fawcett, J., Russell, D. R., Gilani, S. R. & Palma, V. (1999). Acta Cryst. C55, 1707-1710.]); Kaitner & Pavlovic (1995[Kaitner, B. & Pavlovic, G. (1995). Acta Cryst. C51, 1875-1878.]); Li (2010[Li, X.-F. (2010). Acta Cryst. E66, o2417.]); Li et al. (2008[Li, J., Liang, Z.-P. & Tai, X.-S. (2008). Acta Cryst. E64, o2319.]); Yeap et al. (1993[Yeap, G.-Y., Teo, S.-B., Fun, H.-K. & Teoh, S.-G. (1993). Acta Cryst. C49, 1396-1398.]); Zhang (2010[Zhang, F.-G. (2010). Acta Cryst. E66, o382.]). For bond geometry, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L. & Orpen, A. G. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data

  • C14H13NO

  • Mr = 211.25

  • Orthorhombic, P b c n

  • a = 21.618 (1) Å

  • b = 11.0561 (6) Å

  • c = 9.3318 (5) Å

  • V = 2230.4 (2) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 296 K

  • 0.30 × 0.20 × 0.20 mm
Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1999[Bruker (1999). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.977, Tmax = 0.984

  • 11344 measured reflections

  • 1961 independent reflections

  • 1559 reflections with I > 2σ(I)

  • Rint = 0.028
Refinement

  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.100

  • S = 1.08

  • 1961 reflections

  • 148 parameters

  • H-atom parameters constrained

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.14 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1⋯N1i 0.88 1.87 2.7397 (17) 170
Symmetry code: (i) [-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812007635/zs2179sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812007635/zs2179Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812007635/zs2179Isup3.cml

checkCIF report


Comment top

Schiff base compounds have attracted attention for the development of coordination chemistry related to catalysis and enzymatic reactions, magnetism and molecular architectures, e.g. (E)-2-methyl-N-[4-(methylsulfonyl)-benzylidene]aniline (Qian & Cui, 2009). As a part of our study on the coordination behaviour of ligands, an X-ray structural analysis of the title compound, C14H13NO (I) was carried out and the results are reported herein.

The molecule (I) (Fig. 1) may be described in terms of three planar subunits, namely two terminal benzene rings and their substituents bridged by a C═N imino moiety. The 4-hydroxybenzylidene system is nearly planar with r.m.s deviation of 0.0023 Å except for the hydroxy atom O1 which is 0.0183 Å out of the C9—C14 plane. The 4-methylbenzene system which is also essentially planar [r.m.s deviation, 0.0109 Å] except for the methyl atom C1 which is 0.0128Å out of the C2—C7 plane. The molecule has an E-configuration with respect to the C═N which is indicated by the torsion angle C9—C8—N1—C5 [-171.11 (13)°]. The twisting angles of the 4-hydroxybenzylidene and 4-methylbenzylidene groups with respect to the plane defined by the C5—N1—C8—C9 subunit [16.61 (15)° and 34.66 (10)°, respectively], are consistent with the general trend observed previously of aniline rings being more twisted than benzylidene rings, e.g. in 4-[(3-methoxyphenylimino)methyl]phenol [Yeap et al., 1993] and N-p-tolylvanillaldimine [Kaitner & Pavlovic, 1995] and in four N-(2-hydroxybenzylidene)aniline derivatives [Burgess et al., 1999]; 2-chloro-N-[4-(dimethylamino)benzylidene]aniline [Li et al., 2008); 4-bromo-N-[4-(diethylamino)benzylidene]aniline [Li, 2010]; (4-chloro-N-[4-(diethylamino)benzylidene]aniline [Zhang, 2010]. The C9—C8 and N1—C5 bond distances [1.451 (2) and 1.4221 (19) Å] confirm π-electron delocalization between the benzene rings, and the molecule can be regarded as a partially delocalized π-electron system as observed in related structures (Yeap et al., 1993; Kaitner & Pavlovic, 1995). In benzylideneaniline, where the phenyl ring has no substituents, the aromatic C—(Csp2), (Csp2) ═N and N—Car bond lengths of the azomethine portion are 1.496 (3), 1.237 (3) and 1.460 (3) Å, respectively (Kaitner & Pavlovic, 1995). If the terminal phenyl rings of benzylideneaniline have different substituents, the general pattern of two long and one short bond distance is not preserved. Contrary to this, the shortening of N—Car and aromatic C—(Csp2) [1.4221 (19) Å and 1.451 (2) Å. respectively] and the lengthening of N═(Csp2) [1.279 (2) Å] is observed in (I) and in similar structures (Yeap et al., 1993; Kaitner & Pavlovic, 1995). In (I), the two longer bonds are also shortened, while the shorter bond has lengthened, compared to the parent compound. The C2—C1 bond distance of 1.504 (2) Å is in good agreement with the aromatic C—(Csp3) bond lengths. Using a 3σ criterion, the lengths of O1—C12 [1.3496 (18) Å] is the same and fall into the range for the O—Car bond type. Expansion of the exocyclic angle O1—C12—C11 [123.45 (14)°] may be due to the steric interaction atoms H11 and H1 [H1···H1 = 2.3029 (1) Å]. The N1—C8—C9 [124.80 (14)°] is greater than the normal value of 120°. This might be a consequence of repulsion between the lone pair of electrons on N1 and H10 attached to C10 [N1···H10 = 2.6892 (1) Å]. All other bond lengths are within the expected ranges (Allen et al., 1987).

The crystal structure is stabilized by intermolecular hydroxy O—H···N hydrogen bonds (Table 1) linking the molecules into infinite one-dimensional chains extending along the c axis of the unit cell (Fig. 2).

Related literature top

For the applications of Schiff bases, see: Qian & Cui (2009). For related structures, see: Burgess et al. (1999); Kaitner & Pavlovic (1995); Li (2010); Li et al. (2008); Yeap et al. (1993); Zhang (2010). For bond geometry, see: Allen et al. (1987).

Experimental top

The title compound (I) was prepared by mixing equimolar quantities (10 mmol) of 4-hydroxybenzaldehyde and 4-methylaniline in ethanol (40 ml). The reaction mixture was refluxed for about 6 h and the resulting solution was allowed to slowly evaporate at room temperature. After three days colourless single crystals of the title compound, suitable for X-ray structure analysis were obtained.

Refinement top

All of the H atoms were positioned geometrically and treated as riding on their parent atoms, with O—H = 0.88 Å, C—H = 0.93 Å (aromatic) or 0.96 Å (methyl), and refined using a riding model with Uiso(H) = 1.2Ueq(O or aromatic C) or 1.5Ueq(methyl C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing atom numbering, with displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. A perspective view of the one-dimensional chain structure in the title compound showing O—H···N interactions as dashed lines. For symmetry code (i), see Table 1.
4-[(E)-(4-Methylphenyl)iminomethyl]phenol top
Crystal data top
C14H13NOF(000) = 896
Mr = 211.25Dx = 1.258 Mg m−3
Orthorhombic, PbcnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2n 2abCell parameters from 2333 reflections
a = 21.618 (1) Åθ = 2.5–24.3°
b = 11.0561 (6) ŵ = 0.08 mm−1
c = 9.3318 (5) ÅT = 296 K
V = 2230.4 (2) Å3Needle, colourless
Z = 80.30 × 0.20 × 0.20 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer		1961 independent reflections
Radiation source: fine-focus sealed tube1559 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ω and ϕ scansθmax = 25.0°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Bruker, 1999)		h = −25→22
Tmin = 0.977, Tmax = 0.984k = −13→13
11344 measured reflectionsl = −9→11
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) = 0.100 w = 1/[σ2(Fo2) + (0.0452P)2 + 0.5906P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max < 0.001
1961 reflectionsΔρmax = 0.19 e Å−3
148 parametersΔρmin = −0.14 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0028 (10)
Crystal data top
C14H13NOV = 2230.4 (2) Å3
Mr = 211.25Z = 8
Orthorhombic, PbcnMo Kα radiation
a = 21.618 (1) ŵ = 0.08 mm−1
b = 11.0561 (6) ÅT = 296 K
c = 9.3318 (5) Å0.30 × 0.20 × 0.20 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer		1961 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1999)		1559 reflections with I > 2σ(I)
Tmin = 0.977, Tmax = 0.984Rint = 0.028
11344 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.100H-atom parameters constrained
S = 1.08Δρmax = 0.19 e Å−3
1961 reflectionsΔρmin = −0.14 e Å−3
148 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
C10.98404 (9)−0.3138 (2)0.5166 (2)0.0696 (6)
H1A1.0178−0.27130.56050.104*
H1B0.9999−0.37380.45190.104*
H1C0.9597−0.35250.58940.104*
C20.94434 (7)−0.22573 (15)0.43514 (19)0.0463 (4)
C30.93867 (8)−0.10700 (16)0.47974 (19)0.0480 (4)
H30.9599−0.08140.56100.058*
C40.90213 (7)−0.02566 (14)0.40601 (18)0.0424 (4)
H40.90010.05440.43630.051*
C50.86863 (7)−0.06207 (13)0.28760 (16)0.0344 (4)
C60.87510 (8)−0.18013 (14)0.23975 (18)0.0425 (4)
H60.8543−0.20550.15780.051*
C70.91231 (8)−0.25992 (15)0.31352 (19)0.0484 (5)
H70.9160−0.33900.28050.058*
C80.78057 (7)−0.01218 (13)0.15734 (16)0.0364 (4)
H80.7683−0.09150.17440.044*
C90.74169 (7)0.06129 (13)0.06518 (16)0.0343 (4)
C100.76120 (7)0.17174 (13)0.00844 (16)0.0348 (4)
H100.79930.20330.03590.042*
C110.72512 (7)0.23468 (12)−0.08724 (16)0.0350 (4)
H110.73890.3083−0.12340.042*
C120.66836 (7)0.18910 (13)−0.13011 (16)0.0344 (4)
C130.64808 (7)0.07966 (13)−0.07395 (18)0.0407 (4)
H130.60990.0486−0.10110.049*
C140.68428 (7)0.01724 (13)0.02146 (18)0.0402 (4)
H140.6702−0.05610.05780.048*
N10.83053 (6)0.02412 (11)0.21682 (13)0.0350 (3)
O10.63156 (5)0.24423 (10)−0.22698 (13)0.0457 (3)
H10.64750.3149−0.25000.055*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0601 (12)0.0750 (14)0.0738 (14)0.0191 (11)−0.0089 (11)0.0190 (11)
C20.0391 (9)0.0503 (10)0.0494 (10)0.0064 (7)0.0030 (8)0.0115 (8)
C30.0432 (9)0.0570 (11)0.0438 (10)−0.0041 (8)−0.0069 (8)0.0037 (8)
C40.0452 (9)0.0386 (9)0.0434 (9)−0.0012 (7)0.0005 (8)−0.0019 (7)
C50.0370 (8)0.0334 (8)0.0330 (8)0.0014 (6)0.0036 (7)0.0037 (6)
C60.0498 (9)0.0379 (9)0.0398 (9)0.0047 (7)−0.0027 (7)−0.0021 (7)
C70.0541 (10)0.0376 (9)0.0535 (11)0.0108 (8)0.0018 (9)0.0014 (8)
C80.0428 (8)0.0282 (8)0.0382 (9)0.0015 (6)0.0069 (7)0.0025 (6)
C90.0389 (8)0.0289 (7)0.0350 (8)0.0042 (6)0.0044 (7)−0.0007 (6)
C100.0367 (8)0.0317 (8)0.0360 (9)−0.0007 (6)0.0015 (7)−0.0011 (6)
C110.0424 (8)0.0260 (7)0.0365 (9)−0.0006 (6)0.0034 (7)0.0015 (6)
C120.0387 (8)0.0301 (8)0.0345 (9)0.0066 (6)0.0013 (7)−0.0032 (6)
C130.0361 (8)0.0322 (8)0.0536 (11)−0.0024 (7)−0.0016 (8)0.0000 (7)
C140.0424 (9)0.0278 (8)0.0503 (10)−0.0011 (6)0.0041 (8)0.0045 (7)
N10.0403 (7)0.0316 (7)0.0332 (7)0.0040 (5)0.0017 (6)0.0007 (5)
O10.0480 (7)0.0368 (6)0.0522 (7)−0.0011 (5)−0.0115 (6)0.0080 (5)
Geometric parameters (Å, º) top
C1—C21.504 (2)C8—N11.279 (2)
C1—H1A0.9600C8—C91.451 (2)
C1—H1B0.9600C8—H80.9300
C1—H1C0.9600C9—C141.394 (2)
C2—C71.382 (2)C9—C101.396 (2)
C2—C31.383 (2)C10—C111.375 (2)
C3—C41.381 (2)C10—H100.9300
C3—H30.9300C11—C121.386 (2)
C4—C51.381 (2)C11—H110.9300
C4—H40.9300C12—O11.3496 (18)
C5—C61.387 (2)C12—C131.390 (2)
C5—N11.4221 (19)C13—C141.372 (2)
C6—C71.378 (2)C13—H130.9300
C6—H60.9300C14—H140.9300
C7—H70.9300O1—H10.8811
C2—C1—H1A109.5N1—C8—C9124.80 (14)
C2—C1—H1B109.5N1—C8—H8117.6
H1A—C1—H1B109.5C9—C8—H8117.6
C2—C1—H1C109.5C14—C9—C10117.61 (14)
H1A—C1—H1C109.5C14—C9—C8119.57 (13)
H1B—C1—H1C109.5C10—C9—C8122.63 (13)
C7—C2—C3117.54 (15)C11—C10—C9121.17 (13)
C7—C2—C1121.59 (17)C11—C10—H10119.4
C3—C2—C1120.87 (17)C9—C10—H10119.4
C4—C3—C2121.28 (16)C10—C11—C12120.39 (14)
C4—C3—H3119.4C10—C11—H11119.8
C2—C3—H3119.4C12—C11—H11119.8
C3—C4—C5120.58 (15)O1—C12—C11123.45 (14)
C3—C4—H4119.7O1—C12—C13117.38 (13)
C5—C4—H4119.7C11—C12—C13119.16 (14)
C4—C5—C6118.63 (14)C14—C13—C12120.19 (14)
C4—C5—N1118.68 (13)C14—C13—H13119.9
C6—C5—N1122.66 (14)C12—C13—H13119.9
C7—C6—C5120.04 (16)C13—C14—C9121.47 (14)
C7—C6—H6120.0C13—C14—H14119.3
C5—C6—H6120.0C9—C14—H14119.3
C6—C7—C2121.84 (16)C8—N1—C5118.71 (13)
C6—C7—H7119.1C12—O1—H1109.5
C2—C7—H7119.1
C7—C2—C3—C40.3 (3)C8—C9—C10—C11174.95 (14)
C1—C2—C3—C4−179.72 (16)C9—C10—C11—C12−0.3 (2)
C2—C3—C4—C52.0 (2)C10—C11—C12—O1−177.82 (13)
C3—C4—C5—C6−3.5 (2)C10—C11—C12—C130.7 (2)
C3—C4—C5—N1178.62 (14)O1—C12—C13—C14177.90 (14)
C4—C5—C6—C72.7 (2)C11—C12—C13—C14−0.7 (2)
N1—C5—C6—C7−179.48 (14)C12—C13—C14—C90.3 (2)
C5—C6—C7—C2−0.4 (3)C10—C9—C14—C130.1 (2)
C3—C2—C7—C6−1.1 (3)C8—C9—C14—C13−175.12 (14)
C1—C2—C7—C6178.95 (17)C9—C8—N1—C5−171.11 (13)
N1—C8—C9—C14−171.69 (15)C4—C5—N1—C8−147.79 (14)
N1—C8—C9—C1013.4 (2)C6—C5—N1—C834.4 (2)
C14—C9—C10—C11−0.1 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i0.881.872.7397 (17)170
Symmetry code: (i) −x+3/2, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formulaC14H13NO
Mr211.25
Crystal system, space groupOrthorhombic, Pbcn
Temperature (K)296
a, b, c (Å)21.618 (1), 11.0561 (6), 9.3318 (5)
V (Å3)2230.4 (2)
Z8
Radiation typeMo Kα
µ (mm−1)0.08
Crystal size (mm)0.30 × 0.20 × 0.20
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1999)
Tmin, Tmax0.977, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections		11344, 1961, 1559
Rint0.028
(sin θ/λ)max (Å−1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.100, 1.08
No. of reflections1961
No. of parameters148
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.19, −0.14

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···N1i0.881.872.7397 (17)170
Symmetry code: (i) −x+3/2, −y+1/2, z−1/2.
 

Acknowledgements

LJ thanks the Sophisticated Analytical Instrument Facility, IIT Madras, Chennai, for the single-crystal X-ray data collection.

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L. & Orpen, A. G. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CrossRef Google Scholar
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ISSN: 2056-9890
Volume 68| Part 3| March 2012| Page o897
doi:10.1107/S1600536812007635
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