2-Bromo-N′-[(E)-4-hydroxy­benzyl­idene]-5-methoxy­benzohydrazide

The geometric parameters of the title compound, C₁₅H₁₃BrN₂O₃, are in the usual ranges. The C=N double bond is trans configured. The C=N—N—CO– group itself is planar, with an r.m.s. deviation of 0.044 Å, and makes a dihedral angle of 10.73 (19)° with the hydroxy­phenyl ring, but forms a dihedral angle of 67.90 (8)° with the other aromatic ring. The crystal packing is stabilized by N—H...O, O—H...O and O—H...N hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.032
• wR factor = 0.064
• Data-to-parameter ratio = 17.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.94
PLAT222_ALERT_3_C Large Non-Solvent    H     Ueq(max)/Ueq(min) ...       3.45 Ratio
PLAT431_ALERT_2_C Short Inter HL..A Contact  Br1    ..  O17     ..       3.33 Ang.

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      0.935
            Tmax scaled      0.541 Tmin scaled      0.497
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           27.56
           From the CIF: _reflns_number_total               3536
           Count of symmetry unique reflns         2039
           Completeness (_total/calc)            173.42%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1497
           Fraction of Friedel pairs measured     0.734
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   2 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 bases are known to have biological activities such as antimicrobial (El-Masry et al., 2000; Pandey et al., 1999), antifungal (Singh et al., 1988; Varma et al., 1986), antitumor (Hodnett et al., 1970; Misra et al. 1981; Desai et al., 2001), and as herbicides. Schiff bases have also been employed as ligands for complexation of metal ions (Aydoğan et al., 2001). On the industrial scale, they have wide range of applications such as dyes and pigments (Taggi et al., 2002). The crystal structures of 2-bromo-N-[(E)-4-chlorobenzylidene]-5-methoxybenzohydrazide (Butcher et al., 2007), 2-bromo-5-methoxy-N-[(E)-(2-nitrophenyl)methylene]benzohydrazide (Yathirajan et al., 2007), 2-bromo-N-[(E)-(4-fluorophenyl)methylene]-5-methoxybenzohydrazide monohydrate (Narayana et al., 2007), N'-[(1E)-(5-chloro-2-hydroxyphenyl)(phenyl)methylene]-2-hydroxybenzohydrazide (Chang et al., 2007), 2'-(3,4-dimethoxybenzylidene)-2-hydroxybenzohydrazide, (Yang & Pan, 2004) and 2'-(2-fluorobenzylidene)-2-hydroxybenzohydrazide (Yang & Pan, 2005) have been reported. A new Schiff base, C₁₅H₁₃BrN₂O₃, was synthesized and its crystal structure is here reported.

Geometric parameters of the title compound (Fig. 1) are in the usual ranges. The C═N double bond is trans configured. The C═N—N—CO– moiety itself is planar (r.m.s. deviation 0.044 Å). It makes a dihedral angle of 10.73 (19)°, with the hydroxyphenyl ring, but forms a dihedral angle of 67.90 (8)° with the other aromatic ring. The crystal packing is stabilized by N—H···O, O—H···O and O—H···N hydrogen bonds. The hydroxyl group forms a bifurcated H bond to the hydrazon N atom and the carbonyl group.

Related literature

For related structures, see: Yang & Pan (2004; 2005); Butcher et al. (2007); Chang et al. (2007); Narayana et al. (2007); Yathirajan et al. (2007). For related literature, see: Hodnett & Dunn (1970); Misra et al. (1981); Varma et al. (1986); Singh & Dash (1988); Pandey et al. (1999); El-Masry et al. (2000); Aydoğan et al. (2001); Desai et al. (2001); Taggi et al. (2002).

S2. Experimental

A mixture of 2-bromo-5-methoxybenzohydrazide (0.735 g, 0.003 mol) and 4-hydroxybenzaldehyde (0.366 g, 0.003 mol) in 15 ml of absolute ethanol containing 2 drops of sulfuric acid was refluxed for about 3 h. On cooling, the solid separated was filtered and recrystalized from DMF (m.p.: above 523 K). Analysis found: C 51.51, H 3.71, N 7.95%; C₁₅H₁₃BrN₂O₃, requires: C 51.60, H 3.75, N 8.02%.

S3. Refinement

H atoms were found in a difference map, but those bonded to C were refined using a riding model with C—H = 0.95 Å and U_iso(H) = 1.2U_eq(C) for C_aromatic and C—H = 0.98 Å and U_iso(H) = 1.5U_eq(C) for C_methyl. The methyl group was allowed to rotate but not to tip. The H atoms bonded to N and O were freely refined.

Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA [Or X-RED ?]; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. Perspective view of the title compound with the atom numbering; displacement ellipsoids are at the 50% probability level.
	Fig. 2. The formation of the title compound.

2-Bromo-N'-[(E)-4-hydroxybenzylidene]-5-methoxybenzohydrazide

Crystal data

C15H13BrN2O3	F(000) = 704
Mr = 349.18	Dx = 1.503 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 13820 reflections
a = 9.4902 (6) Å	θ = 3.9–27.7°
b = 10.9347 (8) Å	µ = 2.68 mm^−1
c = 14.8687 (10) Å	T = 173 K
V = 1542.96 (18) Å^3	Block, colourless
Z = 4	0.27 × 0.25 × 0.23 mm

Data collection

Stoe IPDSII two-circle diffractometer	3536 independent reflections
Radiation source: fine-focus sealed tube	3204 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.044
ω scans	θmax = 27.6°, θmin = 4.0°
Absorption correction: multi-scan (MULABS; Spek, 2003; Blessing, 1995)	h = −12→10
Tmin = 0.532, Tmax = 0.578	k = −14→11
13120 measured reflections	l = −19→19

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.032	w = 1/[σ^2(Fo^2) + (0.0288P)^2 + 0.3101P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.064	(Δ/σ)max = 0.001
S = 1.06	Δρmax = 0.37 e Å^−3
3536 reflections	Δρmin = −0.58 e Å^−3
200 parameters	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0078 (8)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), with 1510 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.004 (8)

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	0.82669 (3)	0.43390 (3)	0.193021 (18)	0.03868 (10)
C1	0.6507 (2)	0.6879 (2)	0.18939 (15)	0.0214 (5)
O1	0.6900 (3)	0.78219 (16)	0.22737 (11)	0.0330 (5)
O2	0.0445 (2)	0.60418 (16)	0.63181 (11)	0.0272 (4)
H2	0.068 (5)	0.664 (4)	0.665 (3)	0.076 (14)*
N1	0.5450 (2)	0.6169 (2)	0.21810 (12)	0.0241 (4)
H1	0.527 (3)	0.552 (3)	0.1878 (17)	0.022 (6)*
N2	0.4773 (2)	0.64534 (18)	0.29896 (13)	0.0232 (4)
C2	0.3686 (2)	0.5793 (2)	0.31537 (15)	0.0237 (5)
H2A	0.3412	0.5197	0.2723	0.028*
C11	0.7159 (3)	0.6461 (2)	0.10162 (15)	0.0211 (5)
C12	0.7929 (3)	0.5383 (2)	0.09271 (16)	0.0247 (5)
C13	0.8508 (3)	0.5061 (3)	0.00963 (17)	0.0319 (6)
H13	0.9046	0.4332	0.0040	0.038*
C14	0.8296 (3)	0.5809 (3)	−0.06481 (15)	0.0324 (5)
H14	0.8690	0.5590	−0.1213	0.039*
C15	0.7508 (3)	0.6875 (3)	−0.05688 (16)	0.0275 (6)
C16	0.6950 (3)	0.7216 (2)	0.02622 (15)	0.0234 (5)
H16	0.6431	0.7955	0.0318	0.028*
O17	0.7327 (2)	0.7531 (2)	−0.13480 (12)	0.0392 (5)
C17	0.6250 (4)	0.8451 (3)	−0.1348 (2)	0.0440 (8)
H17A	0.5357	0.8090	−0.1149	0.066*
H17B	0.6139	0.8779	−0.1957	0.066*
H17C	0.6517	0.9112	−0.0937	0.066*
C21	0.2849 (3)	0.5918 (2)	0.39774 (14)	0.0214 (5)
C22	0.1683 (3)	0.5158 (2)	0.40985 (14)	0.0260 (5)
H22	0.1440	0.4586	0.3643	0.031*
C23	0.0871 (3)	0.5224 (2)	0.48754 (16)	0.0258 (5)
H23	0.0065	0.4717	0.4945	0.031*
C24	0.1255 (3)	0.6041 (2)	0.55512 (14)	0.0205 (5)
C25	0.2405 (3)	0.6819 (2)	0.54426 (17)	0.0239 (5)
H25	0.2646	0.7383	0.5903	0.029*
C26	0.3199 (3)	0.6764 (2)	0.46560 (14)	0.0252 (5)
H26	0.3979	0.7299	0.4577	0.030*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.04558 (16)	0.03697 (14)	0.03348 (13)	0.01019 (15)	−0.00287 (13)	0.00721 (12)
C1	0.0258 (13)	0.0210 (10)	0.0173 (9)	−0.0010 (9)	0.0012 (10)	−0.0001 (9)
O1	0.0473 (13)	0.0280 (9)	0.0236 (7)	−0.0128 (10)	0.0101 (9)	−0.0082 (7)
O2	0.0409 (11)	0.0212 (9)	0.0195 (7)	−0.0053 (8)	0.0122 (8)	−0.0018 (7)
N1	0.0281 (11)	0.0262 (11)	0.0180 (9)	−0.0055 (9)	0.0068 (8)	−0.0077 (8)
N2	0.0271 (10)	0.0270 (10)	0.0154 (8)	0.0011 (8)	0.0064 (9)	−0.0035 (8)
C2	0.0282 (12)	0.0240 (12)	0.0189 (9)	0.0019 (10)	0.0023 (9)	−0.0016 (9)
C11	0.0220 (12)	0.0224 (12)	0.0188 (10)	−0.0060 (10)	0.0024 (9)	−0.0031 (8)
C12	0.0256 (14)	0.0246 (13)	0.0239 (11)	0.0005 (10)	−0.0013 (9)	−0.0013 (9)
C13	0.0303 (16)	0.0316 (14)	0.0338 (13)	0.0099 (12)	0.0025 (11)	−0.0088 (10)
C14	0.0340 (13)	0.0398 (15)	0.0232 (10)	0.0041 (15)	0.0083 (11)	−0.0064 (10)
C15	0.0294 (15)	0.0355 (15)	0.0177 (11)	−0.0026 (12)	0.0026 (10)	−0.0002 (10)
C16	0.0230 (15)	0.0251 (12)	0.0222 (10)	−0.0043 (11)	0.0049 (10)	−0.0022 (9)
O17	0.0472 (13)	0.0501 (13)	0.0204 (8)	0.0101 (10)	0.0085 (8)	0.0074 (9)
C17	0.052 (2)	0.0474 (19)	0.0329 (14)	0.0081 (15)	0.0011 (13)	0.0137 (13)
C21	0.0248 (12)	0.0220 (12)	0.0174 (9)	0.0016 (9)	0.0019 (8)	−0.0023 (8)
C22	0.0321 (13)	0.0262 (11)	0.0197 (9)	−0.0033 (13)	0.0023 (11)	−0.0065 (8)
C23	0.0286 (14)	0.0257 (12)	0.0230 (11)	−0.0080 (10)	0.0052 (10)	−0.0034 (9)
C24	0.0286 (12)	0.0163 (11)	0.0165 (9)	0.0026 (9)	0.0055 (9)	0.0003 (8)
C25	0.0315 (14)	0.0197 (12)	0.0205 (11)	−0.0010 (11)	0.0039 (10)	−0.0054 (9)
C26	0.0265 (13)	0.0241 (11)	0.0248 (10)	−0.0046 (13)	0.0029 (12)	−0.0023 (9)

Geometric parameters (Å, º)

Br1—C12	1.905 (2)	C15—O17	1.373 (3)
C1—O1	1.234 (3)	C15—C16	1.395 (3)
C1—N1	1.338 (3)	C16—H16	0.9500
C1—C11	1.515 (3)	O17—C17	1.434 (4)
O2—C24	1.375 (3)	C17—H17A	0.9800
O2—H2	0.84 (5)	C17—H17B	0.9800
N1—N2	1.398 (3)	C17—H17C	0.9800
N1—H1	0.86 (3)	C21—C22	1.396 (4)
N2—C2	1.282 (3)	C21—C26	1.409 (3)
C2—C21	1.466 (3)	C22—C23	1.390 (3)
C2—H2A	0.9500	C22—H22	0.9500
C11—C12	1.393 (3)	C23—C24	1.394 (3)
C11—C16	1.406 (3)	C23—H23	0.9500
C12—C13	1.397 (3)	C24—C25	1.392 (4)
C13—C14	1.391 (4)	C25—C26	1.393 (3)
C13—H13	0.9500	C25—H25	0.9500
C14—C15	1.390 (4)	C26—H26	0.9500
C14—H14	0.9500
O1—C1—N1	124.5 (2)	C15—C16—H16	120.1
O1—C1—C11	121.5 (2)	C11—C16—H16	120.1
N1—C1—C11	114.0 (2)	C15—O17—C17	117.1 (2)
C24—O2—H2	110 (3)	O17—C17—H17A	109.5
C1—N1—N2	119.3 (2)	O17—C17—H17B	109.5
C1—N1—H1	117.8 (18)	H17A—C17—H17B	109.5
N2—N1—H1	122.7 (18)	O17—C17—H17C	109.5
C2—N2—N1	114.07 (19)	H17A—C17—H17C	109.5
N2—C2—C21	122.8 (2)	H17B—C17—H17C	109.5
N2—C2—H2A	118.6	C22—C21—C26	119.1 (2)
C21—C2—H2A	118.6	C22—C21—C2	118.8 (2)
C12—C11—C16	119.7 (2)	C26—C21—C2	122.1 (2)
C12—C11—C1	123.5 (2)	C23—C22—C21	121.0 (2)
C16—C11—C1	116.9 (2)	C23—C22—H22	119.5
C11—C12—C13	120.2 (2)	C21—C22—H22	119.5
C11—C12—Br1	121.37 (17)	C22—C23—C24	119.2 (2)
C13—C12—Br1	118.36 (19)	C22—C23—H23	120.4
C14—C13—C12	119.9 (2)	C24—C23—H23	120.4
C14—C13—H13	120.0	O2—C24—C25	122.3 (2)
C12—C13—H13	120.0	O2—C24—C23	116.9 (2)
C15—C14—C13	120.2 (2)	C25—C24—C23	120.9 (2)
C15—C14—H14	119.9	C26—C25—C24	119.7 (2)
C13—C14—H14	119.9	C26—C25—H25	120.1
O17—C15—C14	115.7 (2)	C24—C25—H25	120.1
O17—C15—C16	124.1 (3)	C25—C26—C21	120.1 (2)
C14—C15—C16	120.2 (2)	C25—C26—H26	120.0
C15—C16—C11	119.7 (2)	C21—C26—H26	120.0
O1—C1—N1—N2	−3.6 (4)	C14—C15—C16—C11	−1.5 (4)
C11—C1—N1—N2	179.3 (2)	C12—C11—C16—C15	0.4 (4)
C1—N1—N2—C2	173.1 (2)	C1—C11—C16—C15	−179.2 (2)
N1—N2—C2—C21	178.2 (2)	C14—C15—O17—C17	164.8 (3)
O1—C1—C11—C12	115.3 (3)	C16—C15—O17—C17	−14.7 (4)
N1—C1—C11—C12	−67.5 (3)	N2—C2—C21—C22	−180.0 (2)
O1—C1—C11—C16	−65.2 (3)	N2—C2—C21—C26	−1.1 (4)
N1—C1—C11—C16	112.0 (3)	C26—C21—C22—C23	−0.1 (4)
C16—C11—C12—C13	0.9 (4)	C2—C21—C22—C23	178.7 (2)
C1—C11—C12—C13	−179.6 (2)	C21—C22—C23—C24	−1.7 (4)
C16—C11—C12—Br1	179.08 (19)	C22—C23—C24—O2	−177.9 (2)
C1—C11—C12—Br1	−1.4 (3)	C22—C23—C24—C25	2.3 (4)
C11—C12—C13—C14	−1.1 (4)	O2—C24—C25—C26	179.0 (2)
Br1—C12—C13—C14	−179.3 (2)	C23—C24—C25—C26	−1.2 (4)
C12—C13—C14—C15	−0.1 (4)	C24—C25—C26—C21	−0.6 (4)
C13—C14—C15—O17	−178.2 (3)	C22—C21—C26—C25	1.3 (4)
C13—C14—C15—C16	1.4 (4)	C2—C21—C26—C25	−177.5 (2)
O17—C15—C16—C11	178.0 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O1^i	0.84 (5)	2.07 (4)	2.799 (3)	145 (4)
O2—H2···N2^i	0.84 (5)	2.32 (5)	2.995 (3)	137 (4)
N1—H1···O2^ii	0.86 (3)	2.01 (3)	2.866 (3)	170 (3)

Symmetry codes: (i) x−1/2, −y+3/2, −z+1; (ii) −x+1/2, −y+1, z−1/2.