2-Bromo-4-chloro-6-(4-fluoro­phenyl­imino­meth­yl)phenol

The two mol­ecules of the title compound, C₁₃H₈BrClFNO, in the asymmetric unit are inter­connected by π–π inter­actions between the salicylaldehyde and aniline units, the shortest inter­planar distance being 3.317 (3) Å. These pairs and their translation equivalents are further linked by C—H...F hydrogen bonds, forming a one-dimensional infinite chain. In addition, there is an intra­molecular O—H...N hydrogen bond connecting the OH group and the imine N atom.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.044
• wR factor = 0.138
• Data-to-parameter ratio = 24.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT431_ALERT_2_C Short Inter HL..A Contact  Br1    ..  Br1     ..       3.55 Ang.
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.87
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)        200 Deg.

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.872
            Tmax scaled      0.500 Tmin scaled      0.393
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Monobasic bidentate Schiff base ligands exemplified by the title compound exhibiting both N and O donor sites play an important role in the synthesis of metal complexes and represent an important class of chelating ligands (Sivagamasundari et al., 2007; Prabhakaran et al., 2004). Among the prodigious number and variety of Schiff bases, salicylaldimines have been studied widely because of their synthetic proclivity and structural diversity (Collinson et al., 1996; Garnovski et al., 2002). In recent years, there has been considerable interest in the chemistry of transition metal complexes of Schiff bases. This is due to the fact that Schiff bases offer opportunities for inducing substrate chirality, tuning metal centered electronic properties, enhancing solubility and stability of either homogeneous or heterogeneous catalysts and producing antibacterial agents (Karvembu et al., 2003; Nakajima et al., 1998; Kumar et al., 2004; Ramesh et al., 2003; Kannan et al., 2006). With the above view, in our ongoing research, we have chosen the title compound as a specific and representative ligand to synthesize ruthenium complexes. The title compound and its complexes will be screened against the bacterei E. coli, S.aureous, P.mirabilis and P.vulgaris.

The title compound, C₉H₈BrClFNO, crystallizes in the triclinic space group P1 with one molecule in the asymmetric unit. Figure 1 shows the ORTEP representation of the molecule with thermal ellipsoids at the 50% probability level. The packing of the molecules in the unit cell showing the inter molecular interactions is depicted in Figure 2. The molecule and its inversion analogue are linked to each other by Π-Π interactions between the salicylaldehyde moiety and the aniline moiety with the shortest interplanar distance of 3.317 (3) Å (1 - x, 1 - y, 1 - z). The molecules are further connected by C11—H11···F1 hydrogen bonds (2.452 Å, 161.89°, 1 + x, -1 + y, 1 + z) forming an one- dimensional infinite chain. The packing is further stabilized by Van der Waals interactions. In addition, an intramolecular hydrogen bonding O1—H1···N1 (2.577 (3) Å, 145.9°) linking the OH group of the former salicyleldehyde and the imine N atom. The dihedral angle between the salicylaldehyde and aniline moieties is 8.8 (2)°.

Related literature

For related literature, see: Collinson & Fenton (1996); Garnovski & Vasil Chenko (2002); Kannan & Ramesh (2006); Karvembu et al. (2003); Kumar & Ramesh (2004); Nakajima et al. (1998); Prabhakaran et al. (2004); Ramesh & Maheswaran (2003); Sivagamasundari & Ramesh (2007).

S2. Experimental

The monobasic bidentate Schiff base ligand, 2-bromo-4-chloro-6-[(4' -fluorophenylimino)-methyl]-phenol, was synthesized by the condensation of 3-bromo-5-chloro-2-hydroxybenzaldehyde (0.1 mmol) with 4-fluoroaniline (0.1 mmol) in a 1:1 molar ratio in MeOH (25 cm³). The solution was heated under reflux for 3 h with continuous stirring and then concentrated to 5 cm³. On cooling the pale orange crystalline product precipitated, was filtered off, washed with ice cold EtOH and dried. The product was recrystallized from EtOH. The purity of the compound was checked by TLC.

S3. Refinement

All the H atoms were located from the difference Fourier map. However, the aromatic H atoms were geometrically constrained at idealized positions (C—H = 0.93 Å) and were refined using a riding model with U_iso equal to 1.2 times U_eq of the parent carbon atom. The hydroxyl hydrogen was refined isotropically with restraint: O—H = 0.820 (1) Å.

Computing details

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: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

	Fig. 1. The ORTEP representation of the molecule with thermal ellipsoids at the 50% probability level.
	Fig. 2. Packing of molecules in the unit cell. Intermolecular interactions are shown with dashed lines.

2-Bromo-4-chloro-6-(4-fluorophenyliminomethyl)phenol

Crystal data

C13H8BrClFNO	Z = 2
Mr = 328.56	F(000) = 324
Triclinic, P1	Dx = 1.731 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.2274 (3) Å	Cell parameters from 5635 reflections
b = 8.6566 (3) Å	θ = 2.7–31.1°
c = 10.8880 (4) Å	µ = 3.47 mm^−1
α = 69.545 (2)°	T = 293 K
β = 70.820 (2)°	Rectangle, pale orange
γ = 62.341 (2)°	0.30 × 0.20 × 0.20 mm
V = 630.48 (4) Å^3

Data collection

Bruker APEX2 CCD diffractometer	3975 independent reflections
Radiation source: fine-focus sealed tube	2533 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
ω and ϕ scans	θmax = 30.9°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −11→11
Tmin = 0.451, Tmax = 0.573	k = −12→12
16111 measured reflections	l = −15→15

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.138	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0708P)^2 + 0.3467P] where P = (Fo^2 + 2Fc^2)/3
3975 reflections	(Δ/σ)max = 0.001
164 parameters	Δρmax = 0.72 e Å^−3
0 restraints	Δρmin = −0.56 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
C1	0.3576 (4)	0.9290 (4)	0.1434 (3)	0.0520 (7)
C2	0.3513 (4)	1.0070 (4)	0.2347 (3)	0.0572 (7)
H2	0.2789	1.1284	0.2308	0.069*
C3	0.4551 (4)	0.9013 (4)	0.3333 (3)	0.0501 (6)
H3	0.4523	0.9521	0.3968	0.060*
C4	0.5627 (3)	0.7212 (3)	0.3389 (2)	0.0384 (5)
C5	0.5679 (4)	0.6469 (4)	0.2429 (3)	0.0486 (6)
H5	0.6412	0.5261	0.2448	0.058*
C6	0.4637 (4)	0.7527 (4)	0.1440 (3)	0.0535 (7)
H6	0.4662	0.7040	0.0792	0.064*
C7	0.7801 (4)	0.4644 (3)	0.4552 (3)	0.0405 (5)
H7	0.8117	0.4086	0.3866	0.049*
C8	0.8715 (3)	0.3665 (3)	0.5699 (2)	0.0366 (5)
C9	0.8321 (3)	0.4496 (3)	0.6718 (3)	0.0378 (5)
C10	0.9237 (4)	0.3494 (3)	0.7792 (3)	0.0417 (5)
C11	1.0468 (4)	0.1735 (3)	0.7878 (3)	0.0433 (6)
H11	1.1053	0.1086	0.8607	0.052*
C12	1.0820 (4)	0.0950 (3)	0.6861 (3)	0.0434 (6)
C13	0.9977 (4)	0.1888 (3)	0.5779 (3)	0.0427 (5)
H13	1.0248	0.1338	0.5098	0.051*
N1	0.6581 (3)	0.6243 (3)	0.4471 (2)	0.0402 (5)
O1	0.7120 (3)	0.6194 (2)	0.6688 (2)	0.0525 (5)
H1	0.6570	0.6571	0.6070	0.087 (13)*
F1	0.2529 (3)	1.0312 (3)	0.04826 (19)	0.0759 (6)
Cl1	1.23745 (13)	−0.12851 (9)	0.69813 (9)	0.0681 (2)
Br1	0.87756 (6)	0.45988 (5)	0.91496 (4)	0.07867 (18)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0463 (14)	0.0613 (17)	0.0414 (14)	−0.0219 (13)	−0.0227 (12)	0.0098 (13)
C2	0.0576 (17)	0.0432 (14)	0.0585 (18)	−0.0087 (13)	−0.0269 (14)	0.0004 (13)
C3	0.0554 (16)	0.0432 (14)	0.0507 (15)	−0.0129 (12)	−0.0241 (12)	−0.0063 (12)
C4	0.0385 (12)	0.0400 (12)	0.0367 (12)	−0.0169 (10)	−0.0153 (10)	0.0002 (10)
C5	0.0505 (15)	0.0456 (14)	0.0504 (15)	−0.0129 (12)	−0.0236 (12)	−0.0079 (12)
C6	0.0586 (17)	0.0672 (19)	0.0400 (14)	−0.0264 (15)	−0.0212 (12)	−0.0057 (13)
C7	0.0443 (13)	0.0398 (12)	0.0407 (12)	−0.0146 (10)	−0.0174 (10)	−0.0078 (10)
C8	0.0373 (11)	0.0352 (11)	0.0377 (12)	−0.0126 (9)	−0.0156 (9)	−0.0040 (9)
C9	0.0362 (11)	0.0339 (11)	0.0425 (13)	−0.0089 (9)	−0.0154 (10)	−0.0080 (10)
C10	0.0437 (13)	0.0425 (13)	0.0413 (13)	−0.0127 (10)	−0.0174 (10)	−0.0102 (10)
C11	0.0449 (13)	0.0397 (12)	0.0425 (13)	−0.0128 (10)	−0.0222 (11)	0.0005 (11)
C12	0.0429 (13)	0.0310 (11)	0.0522 (15)	−0.0083 (10)	−0.0200 (11)	−0.0044 (10)
C13	0.0471 (13)	0.0347 (12)	0.0462 (14)	−0.0100 (10)	−0.0177 (11)	−0.0102 (10)
N1	0.0409 (11)	0.0395 (11)	0.0407 (11)	−0.0139 (9)	−0.0183 (9)	−0.0034 (9)
O1	0.0568 (11)	0.0372 (9)	0.0584 (12)	0.0023 (8)	−0.0302 (9)	−0.0173 (8)
F1	0.0744 (12)	0.0842 (14)	0.0574 (11)	−0.0237 (11)	−0.0444 (10)	0.0151 (10)
Cl1	0.0768 (5)	0.0338 (3)	0.0812 (6)	0.0009 (3)	−0.0358 (4)	−0.0126 (3)
Br1	0.0981 (3)	0.0702 (3)	0.0663 (3)	−0.00208 (19)	−0.0451 (2)	−0.03146 (18)

Geometric parameters (Å, º)

C1—F1	1.355 (3)	C7—H7	0.9300
C1—C6	1.361 (5)	C8—C13	1.391 (3)
C1—C2	1.360 (5)	C8—C9	1.399 (3)
C2—C3	1.382 (4)	C9—O1	1.334 (3)
C2—H2	0.9300	C9—C10	1.396 (3)
C3—C4	1.381 (4)	C10—C11	1.373 (4)
C3—H3	0.9300	C10—Br1	1.878 (3)
C4—C5	1.387 (4)	C11—C12	1.379 (4)
C4—N1	1.418 (3)	C11—H11	0.9300
C5—C6	1.386 (4)	C12—C13	1.370 (3)
C5—H5	0.9300	C12—Cl1	1.741 (3)
C6—H6	0.9300	C13—H13	0.9300
C7—N1	1.270 (3)	O1—H1	0.8200
C7—C8	1.460 (3)
F1—C1—C6	118.6 (3)	C13—C8—C9	120.0 (2)
F1—C1—C2	118.5 (3)	C13—C8—C7	119.4 (2)
C6—C1—C2	122.8 (2)	C9—C8—C7	120.5 (2)
C1—C2—C3	118.3 (3)	O1—C9—C10	119.7 (2)
C1—C2—H2	120.9	O1—C9—C8	122.2 (2)
C3—C2—H2	120.9	C10—C9—C8	118.1 (2)
C4—C3—C2	120.9 (3)	C11—C10—C9	122.0 (2)
C4—C3—H3	119.6	C11—C10—Br1	119.22 (18)
C2—C3—H3	119.6	C9—C10—Br1	118.82 (19)
C3—C4—C5	119.2 (2)	C10—C11—C12	118.6 (2)
C3—C4—N1	116.1 (2)	C10—C11—H11	120.7
C5—C4—N1	124.7 (2)	C12—C11—H11	120.7
C6—C5—C4	120.0 (3)	C13—C12—C11	121.5 (2)
C6—C5—H5	120.0	C13—C12—Cl1	120.1 (2)
C4—C5—H5	120.0	C11—C12—Cl1	118.38 (19)
C1—C6—C5	118.8 (3)	C12—C13—C8	119.8 (2)
C1—C6—H6	120.6	C12—C13—H13	120.1
C5—C6—H6	120.6	C8—C13—H13	120.1
N1—C7—C8	121.3 (2)	C7—N1—C4	122.7 (2)
N1—C7—H7	119.3	C9—O1—H1	109.5
C8—C7—H7	119.3
F1—C1—C2—C3	178.5 (3)	O1—C9—C10—C11	179.2 (3)
C6—C1—C2—C3	−1.0 (5)	C8—C9—C10—C11	−1.1 (4)
C1—C2—C3—C4	0.1 (5)	O1—C9—C10—Br1	−1.2 (3)
C2—C3—C4—C5	0.8 (4)	C8—C9—C10—Br1	178.50 (19)
C2—C3—C4—N1	−177.8 (3)	C9—C10—C11—C12	0.8 (4)
C3—C4—C5—C6	−0.9 (4)	Br1—C10—C11—C12	−178.8 (2)
N1—C4—C5—C6	177.6 (2)	C10—C11—C12—C13	0.3 (4)
F1—C1—C6—C5	−178.6 (3)	C10—C11—C12—Cl1	−179.7 (2)
C2—C1—C6—C5	1.0 (5)	C11—C12—C13—C8	−0.9 (4)
C4—C5—C6—C1	0.0 (4)	Cl1—C12—C13—C8	179.0 (2)
N1—C7—C8—C13	177.0 (3)	C9—C8—C13—C12	0.6 (4)
N1—C7—C8—C9	−2.6 (4)	C7—C8—C13—C12	−179.0 (2)
C13—C8—C9—O1	−179.9 (2)	C8—C7—N1—C4	−178.1 (2)
C7—C8—C9—O1	−0.3 (4)	C3—C4—N1—C7	−170.8 (3)
C13—C8—C9—C10	0.4 (4)	C5—C4—N1—C7	10.7 (4)
C7—C8—C9—C10	180.0 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C11—H11···F1^i	0.93	2.45	3.349 (4)	162
O1—H1···N1	0.82	1.86	2.577 (3)	146

Symmetry code: (i) x+1, y−1, z+1.