4-Bromo-N-phenyl­benzamidoxime

Cibian, M.; Ferreira, J.G.; Hanan, G.S.

doi:10.1107/S1600536809040057

organic compounds

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ISSN: 2056-9890

Volume 65| Part 11| November 2009| Page o2820

https://doi.org/10.1107/S1600536809040057

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4-Bromo-N-phenylbenzamidoxime

Mihaela Cibian,^a Janaina G. Ferreira ^a ^* and Garry S. Hanan ^a

^aDépartement de Chimie, Université de Montréal, CP 6128, Succ. Centre-ville, Montréal, Québec, Canada H3C 3J7
^*Correspondence e-mail: j.gomes.ferreira@umontreal.ca

(Received 24 September 2009; accepted 1 October 2009; online 23 October 2009)

The title compound, C₁₃H₁₁BrN₂O, a hydroxyamidine derivative (an amidoxime), was obtained by addition of the corresponding imidoyl chloride to hydroxylamine. The benzene and phenyl rings are twisted from the mean plane of the hydroxyamidine group by 34.4 (1) and 59.2 (1)°, respectively. In the crystal structure, intermolecular O—H⋯N hydrogen bonds link pairs of molecules, forming centrosymmetric dimers.

Related literature

For the synthesis, properties and applications of N-substituted hydroxyamidines/amidoximes see: Krajete et al. (2004 ), Srivastava et al. (1997 ); Dondoni et al. (1975 , 1977 ); Dürüst et al. (2000 , 2008 ); Exner et al. (1974 ); Briggs et al. (1976 ); Deb et al. (1991 ). For a description of the Cambridge Structural Database, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₃H₁₁BrN₂O
M_r = 291.15
Monoclinic, P 2₁ /n
a = 6.1752 (1) Å
b = 15.2628 (3) Å
c = 13.1312 (2) Å
β = 103.415 (1)°
V = 1203.86 (4) Å³
Z = 4
Cu Kα radiation
μ = 4.53 mm⁻¹
T = 200 K
0.18 × 0.15 × 0.09 mm

Data collection

Bruker APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.532, T_max = 0.665
15615 measured reflections
2356 independent reflections
2273 reflections with I > 2σ(I)
R_int = 0.033

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.090
S = 1.11
2356 reflections
155 parameters
H-atom parameters constrained
Δρ_max = 0.39 e Å⁻³
Δρ_min = −0.68 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1ⁱ	0.84	1.99	2.733 (2)	147
Symmetry code: (i) -x+1, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; 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: UdMX (Maris, 2004 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536809040057/lh2914sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809040057/lh2914Isup2.hkl

checkCIF report

Comment top

Although extensively studied for their biological activity (antituberculars, hypotensives), their pharmacological properties (bactericidal, fungicidal, local anaesthetics) (Srivastava, 1997) and also as precursors in the synthesis of cyclic compounds (Dürüst, 2000 and 2008), N-substituted hydroxyamidines/amidoximes have been less investigated concerning their role in coordination and supramolecular chemistry. They act as bidentate ligands to form 5-membered chelate rings with metal ions, forming stable metal complexes. The good electronic delocalization presented by their structures, and the interesting design possibilities, suggest that N-substituted hydroxyamidines/amidoximes and their complexes could be successfully incorporated into supramolecular assemblies based on coordination chemistry and hydrogen bonding. Herein we report the synthesis and crystal structure of a new amidoxime derivative.

The molecular structure of the title compound is shown in Fig. 1. The amidoxime group is present in its neutral form, N—C=N—OH and the bond lengths and angles are within normal ranges (Allen, 1987). The mean planes of the benzene and phenyl rings are tilted with respect to each other by 64.63 (9) ° and, the amidoxime group forms dihedral angles with the benzene and the phenyl rings of 34.4 (1) and 59.2 (1)°, respectively. This value is less than that reported for the bulky substituted N-aryl compound (Krajete, 2004) due to the lesser influence of steric crowding in the title compound.

As illustrated in Fig. 2, the hydrogen bond is of crucial importance to the self-assembly. Molecules are paired by two hydrogen bonds involving the N-hydroxyl group rather than the amidoxime moieties. In the crystal structure, the N-hydroxyl groups participate in hydrogen bonding of the O—H···N type in which two molecules are joined via O—H···N hydrogen bonds to form a dimer across an inversion center (Table 1).

Related literature top

For the synthesis, properties and applications of N-substituted hydroxyamidines/amidoximes see: Krajete et al. (2004), Srivastava et al. (1997); Dondoni et al. (1975, 1977); Dürüst et al. (2000, 2008); Exner et al. (1974); Briggs et al. (1976); Deb et al. (1991). For a description of the Cambridge Structural Database, see: Allen et al. (1987).

Experimental top

The title compound was synthesized according to the procedure of Krajete et al. (2004). 4-Bromo-N-phenylbenzamide (1.5 g, 5.43 mmol) and an excess of thionyl chloride (15 ml) were refluxed for 2 h under nitrogen atmosphere, yielding the corresponding imidoyl chloirde as a pale yellow solid. This compound was dissolved in dry dichlorometane and added drop-wise to a mixture of hydroxylamine hydrochloride (0.4 g, 5.97 mmol) in anhydrous ethanol and triethylamine (3.8 ml, 27.1 mmol) in dry dichloromethane at 195K. The reaction mixture was brought to room temperature and then was heated at reflux for 16 h. The resulting yellow solution was washed with distillated water and the organic materials were subsequently extracted with diethyl ether, dried over anhydrous Na₂SO₄ and filtered. X-ray quality crystals were obtained from a solution of the title compound in aqueous EtOH by slow evaporation at room temperature.

1H NMR (DMSO-d6, 300 MHz, δ, p.p.m.): 10.66 (s, 1H), 8.34 (s, 1H), 7.52(d, J = 8.4 Hz, 2H), 7.30, (d, J= 8.4 Hz, 2H), 7.08 (t, J = 7.8, 7.8 Hz, 2H), 6.80 (t, J =7.3, 7.3 Hz, 1H), 6.65 (d, J = 7.8 Hz, 2H).

Structure description top

For the synthesis, properties and applications of N-substituted hydroxyamidines/amidoximes see: Krajete et al. (2004), Srivastava et al. (1997); Dondoni et al. (1975, 1977); Dürüst et al. (2000, 2008); Exner et al. (1974); Briggs et al. (1976); Deb et al. (1991). For a description of the Cambridge Structural Database, see: Allen et al. (1987).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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: UdMX (Maris, 2004).

Figures top

	Fig. 1. The molecular structure of the title compound (50% probability displacement ellipsoids).
	Fig. 2. A pair of molecules linked through intermolecular N—H···O bonds [Symmetry code: (i)1 - x,1 - y, 2 - z]. Hydrogen bonds are shown as dashed lines.

4-Bromo-N-phenylbenzamidoxime top

Crystal data top

C₁₃H₁₁BrN₂O	F(000) = 584
M_r = 291.15	D_x = 1.606 Mg m⁻³
Monoclinic, P2₁/n	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2yn	Cell parameters from 11676 reflections
a = 6.1752 (1) Å	θ = 2.9–71.9°
b = 15.2628 (3) Å	µ = 4.53 mm⁻¹
c = 13.1312 (2) Å	T = 200 K
β = 103.415 (1)°	Block, yellow
V = 1203.86 (4) Å³	0.18 × 0.15 × 0.09 mm
Z = 4

Data collection top

Bruker APEXII diffractometer	2356 independent reflections
Radiation source: Rotating Anode	2273 reflections with I > 2σ(I)
Montel 200 optics monochromator	R_int = 0.033
Detector resolution: 5.5 pixels mm^-1	θ_max = 72.5°, θ_min = 4.5°
ω scans	h = −7→7
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −18→18
T_min = 0.532, T_max = 0.665	l = −15→16
15615 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.090	w = 1/[σ²(F_o²) + (0.0601P)² + 0.3484P] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max = 0.001
2356 reflections	Δρ_max = 0.39 e Å⁻³
155 parameters	Δρ_min = −0.68 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0212 (8)

Crystal data top

C₁₃H₁₁BrN₂O	V = 1203.86 (4) Å³
M_r = 291.15	Z = 4
Monoclinic, P2₁/n	Cu Kα radiation
a = 6.1752 (1) Å	µ = 4.53 mm⁻¹
b = 15.2628 (3) Å	T = 200 K
c = 13.1312 (2) Å	0.18 × 0.15 × 0.09 mm
β = 103.415 (1)°

Data collection top

Bruker APEXII diffractometer	2356 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2273 reflections with I > 2σ(I)
T_min = 0.532, T_max = 0.665	R_int = 0.033
15615 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.090	H-atom parameters constrained
S = 1.11	Δρ_max = 0.39 e Å⁻³
2356 reflections	Δρ_min = −0.68 e Å⁻³
155 parameters

Special details top

Experimental. X-ray crystallographic data for (I) were collected from a single-crystal sample, which was mounted on a loop fiber. Data were collected using a Bruker Platform diffractometer, equipped with a Bruker SMART 4 K Charged-Coupled Device (CCD) Area Detector using the program APEX2 and a Nonius FR591 rotating anode equiped with a Montel 200 optics The crystal-to-detector distance was 5.0 cm, and the data collection was carried out in 512 x 512 pixel mode. The initial unit-cell parameters were determined by a least-squares fit of the angular setting of strong reflections, collected by a 10.0 degree scan in 33 frames over four different parts of the reciprocal space (133 frames total). One complete sphere of data was collected, to better than 0.80Å resolution.

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

	x	y	z	U_iso*/U_eq
Br	1.22913 (4)	0.643427 (14)	0.618702 (18)	0.04819 (16)
O1	0.4208 (2)	0.40817 (9)	0.94989 (11)	0.0393 (3)
H1	0.3752	0.4375	0.9949	0.059*
N1	0.5789 (3)	0.45874 (10)	0.91086 (12)	0.0340 (3)
N2	0.4624 (3)	0.36287 (11)	0.77216 (14)	0.0410 (4)
H2	0.3431	0.3517	0.7958	0.049*
C1	0.5957 (3)	0.42884 (11)	0.82101 (14)	0.0313 (4)
C2	0.7549 (3)	0.47517 (11)	0.77017 (13)	0.0299 (4)
C3	0.9510 (3)	0.50983 (12)	0.83173 (14)	0.0346 (4)
H3	0.9873	0.4994	0.9051	0.041*
C4	1.0932 (3)	0.55912 (13)	0.78747 (15)	0.0368 (4)
H4	1.2261	0.5828	0.8299	0.044*
C5	1.0391 (3)	0.57343 (12)	0.68075 (15)	0.0353 (4)
C6	0.8484 (4)	0.53857 (14)	0.61731 (15)	0.0408 (4)
H6	0.8153	0.5479	0.5438	0.049*
C7	0.7060 (3)	0.48970 (13)	0.66248 (15)	0.0381 (4)
H7	0.5738	0.4659	0.6196	0.046*
C8	0.4934 (3)	0.31015 (12)	0.68770 (14)	0.0337 (4)
C9	0.3113 (3)	0.29434 (13)	0.60544 (16)	0.0386 (4)
H9	0.1703	0.3189	0.6062	0.046*
C10	0.3362 (4)	0.24228 (13)	0.52181 (16)	0.0417 (4)
H10	0.2117	0.2309	0.4656	0.050*
C11	0.5407 (4)	0.20724 (13)	0.52029 (16)	0.0414 (4)
H11	0.5577	0.1726	0.4626	0.050*
C12	0.7220 (3)	0.22247 (14)	0.60292 (17)	0.0418 (5)
H12	0.8629	0.1980	0.6017	0.050*
C13	0.6989 (3)	0.27319 (13)	0.68740 (15)	0.0384 (4)
H13	0.8226	0.2826	0.7446	0.046*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br	0.0483 (2)	0.0459 (2)	0.0568 (2)	−0.00414 (8)	0.02515 (13)	0.00910 (8)
O1	0.0486 (8)	0.0365 (7)	0.0400 (7)	−0.0037 (6)	0.0248 (6)	−0.0008 (5)
N1	0.0401 (8)	0.0326 (8)	0.0336 (7)	0.0003 (6)	0.0173 (6)	0.0020 (6)
N2	0.0419 (9)	0.0438 (9)	0.0439 (10)	−0.0102 (7)	0.0235 (8)	−0.0114 (7)
C1	0.0353 (8)	0.0289 (8)	0.0315 (8)	0.0025 (7)	0.0113 (7)	−0.0001 (6)
C2	0.0346 (8)	0.0272 (8)	0.0300 (8)	0.0029 (6)	0.0118 (7)	0.0004 (6)
C3	0.0399 (9)	0.0362 (9)	0.0280 (8)	0.0020 (7)	0.0088 (7)	0.0005 (7)
C4	0.0353 (9)	0.0370 (9)	0.0380 (9)	−0.0008 (7)	0.0086 (7)	−0.0007 (7)
C5	0.0383 (9)	0.0304 (8)	0.0409 (10)	0.0017 (7)	0.0170 (7)	0.0038 (7)
C6	0.0492 (11)	0.0437 (10)	0.0298 (9)	−0.0029 (9)	0.0101 (8)	0.0063 (8)
C7	0.0422 (10)	0.0403 (10)	0.0306 (9)	−0.0052 (8)	0.0061 (7)	0.0018 (7)
C8	0.0394 (9)	0.0307 (8)	0.0344 (9)	−0.0060 (7)	0.0156 (7)	−0.0028 (7)
C9	0.0377 (9)	0.0352 (9)	0.0439 (10)	−0.0029 (7)	0.0113 (8)	−0.0017 (8)
C10	0.0479 (11)	0.0383 (10)	0.0373 (10)	−0.0075 (8)	0.0065 (8)	−0.0035 (8)
C11	0.0565 (12)	0.0332 (9)	0.0389 (10)	−0.0079 (8)	0.0199 (9)	−0.0072 (7)
C12	0.0410 (10)	0.0356 (10)	0.0534 (11)	−0.0016 (7)	0.0203 (9)	−0.0058 (8)
C13	0.0374 (9)	0.0372 (9)	0.0409 (10)	−0.0031 (7)	0.0099 (8)	−0.0046 (8)

Geometric parameters (Å, º) top

Br—C5	1.9040 (18)	C6—C7	1.387 (3)
O1—N1	1.430 (2)	C6—H6	0.9500
O1—H1	0.8400	C7—H7	0.9500
N1—C1	1.292 (2)	C8—C9	1.388 (3)
N2—C1	1.363 (2)	C8—C13	1.390 (3)
N2—C8	1.419 (2)	C9—C10	1.393 (3)
N2—H2	0.8800	C9—H9	0.9500
C1—C2	1.489 (2)	C10—C11	1.376 (3)
C2—C7	1.394 (2)	C10—H10	0.9500
C2—C3	1.394 (3)	C11—C12	1.386 (3)
C3—C4	1.383 (3)	C11—H11	0.9500
C3—H3	0.9500	C12—C13	1.387 (3)
C4—C5	1.381 (3)	C12—H12	0.9500
C4—H4	0.9500	C13—H13	0.9500
C5—C6	1.382 (3)

N1—O1—H1	109.5	C7—C6—H6	120.5
C1—N1—O1	110.06 (15)	C6—C7—C2	120.66 (17)
C1—N2—C8	127.65 (17)	C6—C7—H7	119.7
C1—N2—H2	116.2	C2—C7—H7	119.7
C8—N2—H2	116.2	C9—C8—C13	120.19 (17)
N1—C1—N2	121.56 (17)	C9—C8—N2	118.38 (18)
N1—C1—C2	116.31 (16)	C13—C8—N2	121.42 (17)
N2—C1—C2	121.95 (16)	C8—C9—C10	119.66 (19)
C7—C2—C3	118.85 (16)	C8—C9—H9	120.2
C7—C2—C1	121.35 (16)	C10—C9—H9	120.2
C3—C2—C1	119.67 (15)	C11—C10—C9	120.21 (19)
C4—C3—C2	120.89 (17)	C11—C10—H10	119.9
C4—C3—H3	119.6	C9—C10—H10	119.9
C2—C3—H3	119.6	C10—C11—C12	120.06 (18)
C5—C4—C3	119.02 (17)	C10—C11—H11	120.0
C5—C4—H4	120.5	C12—C11—H11	120.0
C3—C4—H4	120.5	C11—C12—C13	120.36 (19)
C4—C5—C6	121.51 (17)	C11—C12—H12	119.8
C4—C5—Br	119.69 (15)	C13—C12—H12	119.8
C6—C5—Br	118.80 (14)	C12—C13—C8	119.50 (18)
C5—C6—C7	119.05 (17)	C12—C13—H13	120.3
C5—C6—H6	120.5	C8—C13—H13	120.3

O1—N1—C1—N2	4.8 (2)	Br—C5—C6—C7	−178.10 (16)
O1—N1—C1—C2	179.94 (14)	C5—C6—C7—C2	−0.5 (3)
C8—N2—C1—N1	−164.13 (19)	C3—C2—C7—C6	−0.7 (3)
C8—N2—C1—C2	21.0 (3)	C1—C2—C7—C6	175.18 (18)
N1—C1—C2—C7	−141.09 (18)	C1—N2—C8—C9	−135.4 (2)
N2—C1—C2—C7	34.0 (3)	C1—N2—C8—C13	46.0 (3)
N1—C1—C2—C3	34.7 (2)	C13—C8—C9—C10	−0.9 (3)
N2—C1—C2—C3	−150.13 (18)	N2—C8—C9—C10	−179.53 (17)
C7—C2—C3—C4	1.1 (3)	C8—C9—C10—C11	−0.5 (3)
C1—C2—C3—C4	−174.82 (16)	C9—C10—C11—C12	1.1 (3)
C2—C3—C4—C5	−0.3 (3)	C10—C11—C12—C13	−0.2 (3)
C3—C4—C5—C6	−1.0 (3)	C11—C12—C13—C8	−1.3 (3)
C3—C4—C5—Br	178.52 (14)	C9—C8—C13—C12	1.8 (3)
C4—C5—C6—C7	1.4 (3)	N2—C8—C13—C12	−179.64 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1ⁱ	0.84	1.99	2.733 (2)	147

Symmetry code: (i) −x+1, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₁BrN₂O
M_r	291.15
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	200
a, b, c (Å)	6.1752 (1), 15.2628 (3), 13.1312 (2)
β (°)	103.415 (1)
V (Å³)	1203.86 (4)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	4.53
Crystal size (mm)	0.18 × 0.15 × 0.09

Data collection
Diffractometer	Bruker APEXII
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.532, 0.665
No. of measured, independent and observed [I > 2σ(I)] reflections	15615, 2356, 2273
R_int	0.033
(sin θ/λ)_max (Å⁻¹)	0.619

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.090, 1.11
No. of reflections	2356
No. of parameters	155
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.39, −0.68

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), UdMX (Maris, 2004).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1ⁱ	0.84	1.99	2.733 (2)	147.0

Symmetry code: (i) −x+1, −y+1, −z+2.

Acknowledgements

The authors are grateful to the Natural Sciences and Engineering Research Council of Canada and the University of Montreal for financial assistance and to the Canadian Post-Doctoral Research Fellowship Program (PDRF).

References

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