2,4-Dichloro-6-{[4-chloro-3-(trifluoro­meth­yl)phen­yl]imino­meth­yl}phenol

In the title Schiff base, C₁₄H₇Cl₃F₃NO, one intra­molecular hydrogen bond stabilizes the mol­ecular structure. The dihedral angle between the two benzene rings in the mol­ecule is 47.86 (4)°.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.031
• wR factor = 0.080
• Data-to-parameter ratio = 12.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.96

Alert level C
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C1     -   C2      ..       6.49 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C1
PLAT431_ALERT_2_C Short Inter HL..A Contact  Cl1    ..  F1      ..       3.12 Ang.
PLAT431_ALERT_2_C Short Inter HL..A Contact  Cl2    ..  F3      ..       3.21 Ang.

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Schiff base ligands have significant importance in chemistry, especially, in the development of Schiff base complexes, because Schiff base ligands are potentially capable of forming stable complexes with metal ions (Johnson et al., 1996; Alizadeh et al., 1999; Wang & Zheng, 2007). Schiff bases that have solvent dependent UV/vis spectra (solvatochromicity) can be suitable NLO (nonlinear optical active) materials (Alemi & Shaabani, 2000). They are also useful in asymmetric oxidation of methyl phenyl sulfide and enantioselective (Kim & Shin, 1999). In this paper, we report here the synthesis and crystal structure of the title compound, (I).

The molecular structure of the title compound (Fig. 1) contains one intramolecular hydrogen bond (Table 1). The C8—N1 is 1.278 (2) Å, indicative of standard C=N double bond. The other C—N, C—Cl and C—C distances show no remarkable features. The dihedral angle between two benzene rings in the title molecule is 47.86 (4)°.

Related literature

For related literature, see: Alemi & Shaabani (2000); Alizadeh et al. (1999); Johnson et al. (1996); Kim & Shin (1999); Wang & Zheng (2007).

S2. Experimental

Under nitrogen, a mixture of 4-chloro-3-(trifluoromethyl)benzenamine (1.92 g, 10 mmol), Na₂SO₄ (3.0 g) and 3,5-dichloro-2-hydroxybenzaldehyde (1.66 g, 10 mmol) in absolute ethanol (20 ml) was refluxed for about 12 h to yield a yellow precipitate. The product was collected by vacuum filtration and washed with ethanol. The crude solid was redissolved in CH₂Cl₂ (100 ml) and washed with water (2 × 15 ml) and brine (8 ml). After drying over Na₂SO₄, the solvent was removed under vacuum, and a yellow solid was isolated in 92% yield (3.1 g). Colourless single crystals of the Schiff base, (I), suitable for X-ray analysis were grown from CH₂Cl₂ and absolute ethanol (4:1) by slow evaporation of the solvents at room temperature over a period of about one week.

S3. Refinement

All H atoms were placed in calculated positions (C—H = 0.93 and O—H = 0.82 Å) and refined using a riding model, with U_iso(H) = 1.2U_eq(C) and 1.5U_eq(O).

Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.

Figures

Fig. 1. The molecular structure of (I), showing the atomic numbering scheme. Non-H atoms are shown as 50% probability displacement ellipsoids.

2,4-Dichloro-6-{[4-chloro-3-(trifluoromethyl)phenyl]iminomethyl}phenol

Crystal data

C14H7Cl3F3NO	F(000) = 736
Mr = 368.56	Dx = 1.680 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2502 reflections
a = 8.6093 (6) Å	θ = 1.7–28.0°
b = 22.9730 (16) Å	µ = 0.66 mm^−1
c = 7.9014 (5) Å	T = 298 K
β = 111.204 (1)°	Block, colourless
V = 1456.95 (17) Å^3	0.19 × 0.16 × 0.15 mm
Z = 4

Data collection

Bruker APEX II area-detector diffractometer	2523 independent reflections
Radiation source: fine-focus sealed tube	1704 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.037
φ and ω scans	θmax = 25.2°, θmin = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
Tmin = 0.885, Tmax = 0.907	k = −27→26
8909 measured reflections	l = −8→9

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.080	H-atom parameters constrained
S = 0.90	w = 1/[σ^2(Fo^2) + (0.0476P)^2] where P = (Fo^2 + 2Fc^2)/3
2523 reflections	(Δ/σ)max < 0.001
200 parameters	Δρmax = 0.25 e Å^−3
0 restraints	Δρmin = −0.25 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.15918 (7)	0.52233 (2)	0.33997 (8)	0.0804 (2)
Cl2	0.79951 (8)	0.09612 (2)	0.71667 (8)	0.0815 (2)
Cl3	1.25114 (7)	0.22761 (3)	1.22425 (8)	0.0825 (2)
O1	0.62110 (17)	0.20466 (5)	0.60598 (19)	0.0613 (4)
H1	0.5829	0.2367	0.5663	0.092*
N1	0.59189 (19)	0.31700 (7)	0.6135 (2)	0.0522 (4)
C9	0.8203 (2)	0.26618 (8)	0.8258 (2)	0.0479 (5)
C3	0.2901 (2)	0.46309 (8)	0.4173 (3)	0.0535 (5)
C10	0.7643 (2)	0.21157 (8)	0.7483 (3)	0.0498 (5)
C14	0.9707 (2)	0.27044 (8)	0.9732 (3)	0.0546 (5)
H14	1.0077	0.3066	1.0253	0.066*
C7	0.4266 (2)	0.37778 (8)	0.3681 (3)	0.0532 (5)
H7	0.4491	0.3518	0.2896	0.064*
C8	0.7238 (2)	0.31842 (8)	0.7560 (3)	0.0518 (5)
H8	0.7584	0.3536	0.8161	0.062*
C6	0.4947 (2)	0.36810 (8)	0.5533 (3)	0.0482 (5)
C11	0.8632 (2)	0.16297 (8)	0.8196 (3)	0.0565 (5)
C12	1.0111 (2)	0.16771 (9)	0.9657 (3)	0.0616 (5)
H12	1.0749	0.1348	1.0127	0.074*
C13	1.0638 (2)	0.22165 (9)	1.0415 (3)	0.0569 (5)
C4	0.3564 (2)	0.45298 (9)	0.6018 (3)	0.0587 (5)
H4	0.3321	0.4782	0.6808	0.070*
C2	0.3256 (2)	0.42545 (8)	0.2980 (3)	0.0513 (5)
C5	0.4583 (2)	0.40582 (8)	0.6696 (3)	0.0547 (5)
H5	0.5027	0.3993	0.7942	0.066*
C1	0.2572 (3)	0.43443 (11)	0.0974 (3)	0.0731 (6)
F1	0.09308 (19)	0.43127 (7)	0.02775 (19)	0.1100 (5)
F2	0.3073 (2)	0.39374 (7)	0.00968 (18)	0.1127 (5)
F3	0.2992 (2)	0.48465 (7)	0.0468 (2)	0.1208 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0838 (4)	0.0581 (3)	0.0883 (4)	0.0195 (3)	0.0179 (3)	0.0103 (3)
Cl2	0.1047 (5)	0.0476 (3)	0.0908 (5)	0.0039 (3)	0.0337 (4)	0.0002 (3)
Cl3	0.0610 (3)	0.1032 (5)	0.0728 (4)	0.0193 (3)	0.0113 (3)	−0.0040 (3)
O1	0.0639 (9)	0.0526 (8)	0.0627 (9)	0.0000 (6)	0.0172 (7)	0.0020 (7)
N1	0.0568 (10)	0.0503 (9)	0.0517 (10)	0.0042 (7)	0.0226 (9)	0.0066 (7)
C9	0.0518 (11)	0.0493 (11)	0.0488 (12)	0.0044 (9)	0.0255 (10)	0.0052 (9)
C3	0.0551 (12)	0.0422 (11)	0.0609 (14)	0.0016 (9)	0.0181 (10)	0.0050 (9)
C10	0.0539 (11)	0.0532 (12)	0.0489 (12)	0.0025 (9)	0.0264 (10)	0.0063 (9)
C14	0.0550 (12)	0.0570 (12)	0.0570 (13)	0.0049 (10)	0.0266 (10)	−0.0020 (10)
C7	0.0585 (11)	0.0509 (11)	0.0523 (13)	−0.0019 (9)	0.0225 (10)	−0.0017 (9)
C8	0.0565 (12)	0.0486 (11)	0.0553 (13)	0.0008 (9)	0.0262 (11)	0.0018 (9)
C6	0.0515 (11)	0.0450 (10)	0.0480 (12)	0.0001 (8)	0.0180 (9)	0.0048 (9)
C11	0.0689 (13)	0.0473 (11)	0.0617 (14)	0.0062 (10)	0.0335 (11)	0.0049 (9)
C12	0.0653 (13)	0.0604 (13)	0.0636 (14)	0.0192 (11)	0.0289 (12)	0.0128 (11)
C13	0.0522 (11)	0.0709 (14)	0.0518 (12)	0.0122 (10)	0.0238 (10)	0.0040 (10)
C4	0.0655 (13)	0.0529 (12)	0.0577 (14)	0.0047 (10)	0.0225 (11)	−0.0061 (10)
C2	0.0541 (11)	0.0501 (11)	0.0464 (12)	−0.0030 (9)	0.0142 (9)	0.0065 (9)
C5	0.0591 (12)	0.0554 (12)	0.0478 (12)	0.0046 (9)	0.0172 (10)	0.0022 (9)
C1	0.0815 (17)	0.0714 (16)	0.0591 (15)	0.0084 (13)	0.0167 (13)	0.0058 (12)
F1	0.0860 (10)	0.1488 (15)	0.0682 (10)	0.0080 (9)	−0.0045 (8)	0.0074 (8)
F2	0.1564 (14)	0.1246 (13)	0.0533 (9)	0.0440 (11)	0.0332 (9)	0.0051 (8)
F3	0.1825 (17)	0.0976 (12)	0.0735 (10)	−0.0228 (10)	0.0358 (10)	0.0324 (8)

Geometric parameters (Å, º)

Cl1—C3	1.7314 (19)	C7—C6	1.383 (2)
Cl2—C11	1.731 (2)	C7—C2	1.384 (2)
Cl3—C13	1.738 (2)	C7—H7	0.9300
O1—C10	1.344 (2)	C8—H8	0.9300
O1—H1	0.8200	C6—C5	1.379 (3)
N1—C8	1.278 (2)	C11—C12	1.380 (3)
N1—C6	1.420 (2)	C12—C13	1.380 (3)
C9—C14	1.397 (3)	C12—H12	0.9300
C9—C10	1.403 (2)	C4—C5	1.375 (3)
C9—C8	1.450 (2)	C4—H4	0.9300
C3—C4	1.379 (3)	C2—C1	1.492 (3)
C3—C2	1.392 (3)	C5—H5	0.9300
C10—C11	1.393 (2)	C1—F3	1.314 (3)
C14—C13	1.370 (2)	C1—F1	1.320 (3)
C14—H14	0.9300	C1—F2	1.325 (3)
C10—O1—H1	109.5	C12—C11—Cl2	120.17 (15)
C8—N1—C6	120.14 (16)	C10—C11—Cl2	118.53 (16)
C14—C9—C10	119.68 (17)	C11—C12—C13	119.55 (18)
C14—C9—C8	119.35 (17)	C11—C12—H12	120.2
C10—C9—C8	120.97 (17)	C13—C12—H12	120.2
C4—C3—C2	120.18 (17)	C14—C13—C12	120.67 (19)
C4—C3—Cl1	118.25 (16)	C14—C13—Cl3	119.87 (16)
C2—C3—Cl1	121.56 (15)	C12—C13—Cl3	119.47 (15)
O1—C10—C11	119.00 (17)	C5—C4—C3	120.43 (19)
O1—C10—C9	122.50 (16)	C5—C4—H4	119.8
C11—C10—C9	118.49 (18)	C3—C4—H4	119.8
C13—C14—C9	120.34 (18)	C7—C2—C3	118.71 (17)
C13—C14—H14	119.8	C7—C2—C1	118.97 (19)
C9—C14—H14	119.8	C3—C2—C1	122.32 (18)
C6—C7—C2	121.02 (18)	C4—C5—C6	120.13 (19)
C6—C7—H7	119.5	C4—C5—H5	119.9
C2—C7—H7	119.5	C6—C5—H5	119.9
N1—C8—C9	121.22 (18)	F3—C1—F1	107.0 (2)
N1—C8—H8	119.4	F3—C1—F2	106.4 (2)
C9—C8—H8	119.4	F1—C1—F2	104.2 (2)
C5—C6—C7	119.50 (17)	F3—C1—C2	113.49 (19)
C5—C6—N1	122.99 (17)	F1—C1—C2	112.8 (2)
C7—C6—N1	117.39 (17)	F2—C1—C2	112.34 (19)
C12—C11—C10	121.27 (18)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.88	2.5957 (19)	145