2-Benzyl­imino­meth­yl-6-bromo-4-chloro­phenol

The title mol­ecule, C₁₄H₁₁BrClNO, adopts a trans configuration with respect to the C=N double bond. The dihedral angle between the two aromatic rings is 70.4 (5)°. An intra­molecular O—H...N hydrogen bond is observed between the hydroxyl and imine groups.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.011 Å
• R factor = 0.068
• wR factor = 0.177
• Data-to-parameter ratio = 14.3

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR) is > 1.10
            Tmin and Tmax reported:      0.355     0.676
            Tmin and Tmax expected:      0.285     0.654
            RR =      1.202
            Please check that your absorption correction is appropriate.
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C9
PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...         11
PLAT060_ALERT_4_C Ratio Tmax/Tmin (Exp-to-Rep) (too) Large .......       1.22
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.97

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 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
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Schiff base compounds have been of great interest for many years. These compounds play an important role in the development of coordination chemistry related to catalysis and enzymatic reactions, magnetism and molecular architectures. As an extension of the work on the structural characterization of Schiff base compounds, the crystal structure of the title compound is reported here.

Bond lengths in the title molecule (Fig. 1) have normal values (Allen et al.,1987). The C1═N1 bond length of 1.267 (9) Å conforms to the value for a double bond. The dihedral angle between the two aromatic rings is 70.4 (5)°. As expected, the molecule adopts a trans configuration about the C═N bond [C8—N1—C1—C2 = -178.6 (6)°]. An intramolecular O—H···N hydrogen bond is observed between hydroxyl and imine groups (Table 1).

Related literature

For related literature, see: Ali et al. (2002); Cukurovali et al. (2002); Tarafder et al. (2002). For bond-length data, see: Allen et al. (1987).

S2. Experimental

3-Bromine-5-chlorosalicylaldehyde (0.1 mmol, 23.55 mg) and 1-benzylamine (0.1 mmol, 10.7 mg) were added to methanol (10 ml). The mixture was stirred for 30 min at room temperature to give a clear brown solution. After allowing the resulting solution to stand in air for 7 d, yellow block-shaped crystals of the title compound were formed on slow evaporation of the solvent. The crystals were collected, washed with methanol and dried in a vacuum desiccator using anhydrous CaCl₂ (yield 54%). Analysis found: C 51.76, H 4.0%; calculated for C₁₄H₁₁Br_ClN_O: C 51.77, H 3.39%.

S3. Refinement

All H atoms were placed in geometrically idealized positions [O-H = 0.82 Å and C-H = 0.93–0.97 Å] and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq(C) and 1.5U_eq(O). The highest unassigned peak in the difference map is located 0.85 and 1.05 Å from atoms Cl1 and C6, respectively.

Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of the title compound, showing 30% probability ellipsoids. The dashed line represents a hydrogen bond.
	Fig. 2. The crystal packing of the title compound, viewed down the b axis.

2-Benzyliminomethyl-6-bromo-4-chlorophenol

Crystal data

C14H11BrClNO	F(000) = 648
Mr = 324.60	Dx = 1.617 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2314 reflections
a = 4.3334 (8) Å	θ = 3.0–23.6°
b = 12.8976 (14) Å	µ = 3.27 mm^−1
c = 23.892 (2) Å	T = 298 K
β = 92.992 (1)°	Block, yellow
V = 1333.5 (3) Å^3	0.40 × 0.37 × 0.13 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer	2325 independent reflections
Radiation source: fine-focus sealed tube	1699 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.068
ϕ and ω scans	θmax = 25.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −5→5
Tmin = 0.355, Tmax = 0.676	k = −14→15
6753 measured reflections	l = −28→19

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)] = 0.067	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.176	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0638P)^2 + 4.7838P] where P = (Fo^2 + 2Fc^2)/3
2325 reflections	(Δ/σ)max = 0.001
163 parameters	Δρmax = 1.47 e Å^−3
0 restraints	Δρmin = −0.76 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
Br1	1.1330 (2)	0.05445 (6)	0.34840 (4)	0.0688 (3)
Cl1	1.1495 (6)	0.47661 (15)	0.37758 (10)	0.0761 (6)
N1	0.4056 (13)	0.2399 (4)	0.1816 (2)	0.0495 (14)
O1	0.7218 (12)	0.1150 (3)	0.2472 (2)	0.0588 (13)
H1	0.6061	0.1323	0.2205	0.088*
C1	0.4902 (15)	0.3140 (6)	0.2137 (3)	0.0465 (16)
H1A	0.4104	0.3798	0.2062	0.056*
C2	0.7087 (14)	0.3002 (5)	0.2620 (3)	0.0409 (14)
C3	0.8091 (15)	0.1982 (5)	0.2763 (3)	0.0419 (15)
C4	1.0094 (15)	0.1881 (5)	0.3238 (3)	0.0442 (15)
C5	1.1108 (15)	0.2704 (5)	0.3547 (3)	0.0425 (15)
H5	1.2421	0.2609	0.3864	0.051*
C6	1.0135 (16)	0.3711 (5)	0.3381 (3)	0.0476 (16)
C7	0.8123 (16)	0.3849 (5)	0.2934 (3)	0.0481 (16)
H7	0.7434	0.4511	0.2839	0.058*
C8	0.1902 (16)	0.2605 (6)	0.1331 (3)	0.0562 (19)
H8A	0.0875	0.3264	0.1380	0.067*
H8B	0.0339	0.2066	0.1302	0.067*
C9	0.3671 (15)	0.2630 (6)	0.0799 (3)	0.0480 (17)
C10	0.4684 (18)	0.3549 (7)	0.0600 (3)	0.066 (2)
H10	0.4266	0.4163	0.0786	0.080*
C11	0.635 (2)	0.3571 (9)	0.0117 (4)	0.082 (3)
H11	0.7064	0.4196	−0.0021	0.099*
C12	0.691 (2)	0.2664 (10)	−0.0149 (4)	0.086 (3)
H12	0.8006	0.2675	−0.0473	0.103*
C13	0.594 (2)	0.1762 (9)	0.0043 (4)	0.084 (3)
H13	0.6386	0.1154	−0.0146	0.101*
C14	0.4270 (18)	0.1718 (7)	0.0517 (4)	0.069 (2)
H14	0.3557	0.1087	0.0646	0.083*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0795 (6)	0.0510 (5)	0.0758 (6)	0.0131 (4)	0.0027 (4)	0.0117 (4)
Cl1	0.0979 (16)	0.0525 (11)	0.0767 (14)	−0.0047 (10)	−0.0060 (12)	−0.0098 (10)
N1	0.039 (3)	0.066 (4)	0.044 (3)	0.000 (3)	0.003 (3)	0.003 (3)
O1	0.076 (3)	0.047 (3)	0.053 (3)	0.000 (2)	0.001 (2)	−0.002 (2)
C1	0.039 (4)	0.056 (4)	0.045 (4)	0.002 (3)	0.013 (3)	0.009 (3)
C2	0.039 (3)	0.046 (3)	0.040 (4)	−0.001 (3)	0.016 (3)	0.001 (3)
C3	0.042 (4)	0.042 (3)	0.043 (4)	−0.001 (3)	0.016 (3)	0.001 (3)
C4	0.040 (4)	0.049 (4)	0.045 (4)	0.004 (3)	0.019 (3)	0.008 (3)
C5	0.042 (4)	0.047 (3)	0.039 (4)	0.002 (3)	0.008 (3)	0.001 (3)
C6	0.049 (4)	0.048 (4)	0.046 (4)	−0.001 (3)	0.009 (3)	−0.003 (3)
C7	0.053 (4)	0.042 (3)	0.050 (4)	0.005 (3)	0.011 (3)	0.000 (3)
C8	0.035 (4)	0.078 (5)	0.055 (5)	0.000 (3)	−0.002 (3)	0.001 (4)
C9	0.037 (4)	0.068 (4)	0.038 (4)	0.002 (3)	−0.007 (3)	0.002 (3)
C10	0.052 (5)	0.082 (6)	0.065 (5)	0.000 (4)	−0.002 (4)	0.007 (4)
C11	0.059 (5)	0.115 (8)	0.072 (6)	0.000 (5)	−0.003 (5)	0.028 (6)
C12	0.062 (6)	0.144 (10)	0.051 (6)	0.013 (6)	0.005 (4)	0.006 (6)
C13	0.068 (6)	0.113 (8)	0.070 (6)	0.022 (6)	−0.007 (5)	−0.028 (6)
C14	0.055 (5)	0.081 (6)	0.071 (6)	0.004 (4)	−0.010 (4)	−0.010 (5)

Geometric parameters (Å, º)

Br1—C4	1.890 (6)	C7—H7	0.93
Cl1—C6	1.741 (7)	C8—C9	1.518 (10)
N1—C1	1.267 (9)	C8—H8A	0.97
N1—C8	1.473 (9)	C8—H8B	0.97
O1—C3	1.325 (8)	C9—C10	1.359 (10)
O1—H1	0.82	C9—C14	1.386 (11)
C1—C2	1.465 (9)	C10—C11	1.392 (12)
C1—H1A	0.93	C10—H10	0.93
C2—C7	1.387 (9)	C11—C12	1.360 (14)
C2—C3	1.422 (9)	C11—H11	0.93
C3—C4	1.397 (9)	C12—C13	1.326 (14)
C4—C5	1.353 (9)	C12—H12	0.93
C5—C6	1.416 (9)	C13—C14	1.377 (13)
C5—H5	0.93	C13—H13	0.93
C6—C7	1.355 (9)	C14—H14	0.93
C1—N1—C8	119.5 (6)	N1—C8—H8A	109.7
C3—O1—H1	109.5	C9—C8—H8A	109.7
N1—C1—C2	122.7 (6)	N1—C8—H8B	109.7
N1—C1—H1A	118.7	C9—C8—H8B	109.7
C2—C1—H1A	118.7	H8A—C8—H8B	108.2
C7—C2—C3	120.7 (6)	C10—C9—C14	119.8 (8)
C7—C2—C1	120.6 (6)	C10—C9—C8	119.9 (7)
C3—C2—C1	118.7 (6)	C14—C9—C8	120.3 (7)
O1—C3—C4	120.0 (6)	C9—C10—C11	119.9 (9)
O1—C3—C2	123.2 (6)	C9—C10—H10	120.0
C4—C3—C2	116.9 (6)	C11—C10—H10	120.0
C5—C4—C3	122.7 (6)	C12—C11—C10	118.9 (10)
C5—C4—Br1	117.8 (5)	C12—C11—H11	120.6
C3—C4—Br1	119.4 (5)	C10—C11—H11	120.6
C4—C5—C6	118.9 (6)	C13—C12—C11	121.7 (10)
C4—C5—H5	120.6	C13—C12—H12	119.1
C6—C5—H5	120.6	C11—C12—H12	119.1
C7—C6—C5	120.7 (6)	C12—C13—C14	120.6 (10)
C7—C6—Cl1	120.7 (5)	C12—C13—H13	119.7
C5—C6—Cl1	118.6 (5)	C14—C13—H13	119.7
C6—C7—C2	120.1 (6)	C13—C14—C9	119.0 (9)
C6—C7—H7	120.0	C13—C14—H14	120.5
C2—C7—H7	120.0	C9—C14—H14	120.5
N1—C8—C9	109.6 (5)
C8—N1—C1—C2	−178.6 (6)	C5—C6—C7—C2	−2.7 (10)
N1—C1—C2—C7	175.2 (6)	Cl1—C6—C7—C2	179.2 (5)
N1—C1—C2—C3	−5.7 (9)	C3—C2—C7—C6	0.7 (10)
C7—C2—C3—O1	−178.8 (6)	C1—C2—C7—C6	179.8 (6)
C1—C2—C3—O1	2.1 (9)	C1—N1—C8—C9	102.8 (7)
C7—C2—C3—C4	1.2 (9)	N1—C8—C9—C10	−94.4 (8)
C1—C2—C3—C4	−177.9 (5)	N1—C8—C9—C14	85.3 (8)
O1—C3—C4—C5	178.9 (6)	C14—C9—C10—C11	−0.7 (11)
C2—C3—C4—C5	−1.1 (9)	C8—C9—C10—C11	179.0 (6)
O1—C3—C4—Br1	−3.9 (8)	C9—C10—C11—C12	0.4 (12)
C2—C3—C4—Br1	176.1 (4)	C10—C11—C12—C13	−0.6 (14)
C3—C4—C5—C6	−0.8 (9)	C11—C12—C13—C14	1.0 (14)
Br1—C4—C5—C6	−178.1 (5)	C12—C13—C14—C9	−1.2 (13)
C4—C5—C6—C7	2.7 (10)	C10—C9—C14—C13	1.1 (11)
C4—C5—C6—Cl1	−179.1 (5)	C8—C9—C14—C13	−178.6 (7)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.86	2.590 (7)	147