4-Chloro­benzamidoxime

In the title compound, C₇H₇ClN₂O, an intra­molecular N—H...O hydrogen bond helps to establish the conformation. In the crystal structure, inter­molecular N—H...O and O—H...N hydrogen bonds occur.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.061
• wR factor = 0.179
• Data-to-parameter ratio = 15.4

checkCIF/PLATON results

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Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          5

Alert level G
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
   2 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 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

We report here the crystal structure of the benzonitrile derived title compound, (I), (Fig. 1). The dihedral angle between N2/C7/N1/O and the adjacent bezene ring is 16.30 (11)°. The conformation is stablisied by an intramolecular N—H···O hydrogen bond (Table 1). In the crystal, intermolecular N—H···O and O—H···N interactions occur.

Related literature

Please provide related literature section

S2. Experimental

4-Chloro-benzonitrile (20 mmol) was dissolved in ethanol (8 ml); hydroxylamine hydrochloride (20 mmol) was dissolved in ethanol (6 ml) and potassium carbonate (10 mmol) was dissolved in water (10 ml). The three solutions were mixed and the resulting mixture was refluxed for 24 h. After cooling and filtrating, the crude title compound was obtained and purified by crystallizing from a mixture of ethanol (6 ml) and water (2 ml). Colourless blocks of (I) were obstained by slow evaporation of an ethanol solution. ¹H NMR (CDCl₃, δ, p.p.m.): 7.31–7.32 (m, 2H), 7.62–7.64 (m, 2H), 2.28 (s, 1H), 2.06 (s, 2H).

S3. Refinement

The H atoms were geometrically placed (C—H = 0.93–0.97 Å, N—H = 0.86 Å, O—H = 0.82 Å) and refined as riding with U_iso(H) = 1.2 or 1.5U_eq of the carrier atom.

Computing details

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Siemens, 1996); software used to prepare material for publication: SHELXS97.

Figures

Fig. 1. A view of the molecular structure of (I), showing displacement ellipsoids at the 30% probability level. The dashed line indicates the N—H···O hydrogen bond.

4-Chlorobenzamidoxime

Crystal data

C7H7ClN2O	F(000) = 352
Mr = 170.60	Dx = 1.443 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 7.9930 (16) Å	θ = 10–13°
b = 12.806 (3) Å	µ = 0.43 mm^−1
c = 7.6740 (15) Å	T = 293 K
β = 90.96 (3)°	Block, colourless
V = 785.4 (3) Å^3	0.20 × 0.20 × 0.10 mm
Z = 4

Data collection

Nonius CAD4 diffractometer	978 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.045
Graphite monochromator	θmax = 26.0°, θmin = 2.6°
ω/2θ scans	h = −9→9
Absorption correction: ψ scan (North et al., 1968)	k = 0→15
Tmin = 0.920, Tmax = 0.959	l = 0→9
1653 measured reflections	3 standard reflections every 200 reflections
1544 independent reflections	intensity decay: none

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)] = 0.061	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.179	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0834P)^2 + 0.2545P] where P = (Fo^2 + 2Fc^2)/3
1544 reflections	(Δ/σ)max < 0.001
100 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.27 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
Cl	0.45717 (14)	0.11469 (9)	0.18287 (15)	0.0774 (5)
O1	1.1252 (3)	0.09855 (19)	0.9789 (3)	0.0563 (7)
H1C	1.1124	0.0652	1.0689	0.084*
N1	1.1427 (3)	0.1907 (2)	0.6852 (4)	0.0517 (8)
H1A	1.2254	0.1929	0.7582	0.062*
H1B	1.1478	0.2242	0.5883	0.062*
N2	0.9851 (4)	0.0818 (2)	0.8643 (4)	0.0472 (7)
C1	0.6165 (5)	0.1198 (3)	0.3401 (5)	0.0533 (10)
C2	0.7787 (4)	0.1202 (3)	0.2888 (5)	0.0503 (9)
H2B	0.8045	0.1171	0.1712	0.060*
C3	0.9031 (5)	0.1252 (3)	0.4131 (4)	0.0490 (9)
H3A	1.0139	0.1254	0.3779	0.059*
C4	0.8697 (4)	0.1299 (2)	0.5918 (4)	0.0403 (8)
C5	0.7012 (4)	0.1283 (3)	0.6391 (5)	0.0507 (9)
H5A	0.6740	0.1308	0.7563	0.061*
C6	0.5760 (5)	0.1232 (3)	0.5154 (5)	0.0565 (10)
H6A	0.4647	0.1219	0.5486	0.068*
C7	1.0036 (4)	0.1342 (3)	0.7230 (4)	0.0436 (8)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl	0.0770 (8)	0.0708 (8)	0.0837 (9)	−0.0060 (6)	−0.0208 (6)	0.0085 (6)
O1	0.0697 (17)	0.0537 (16)	0.0454 (14)	−0.0116 (13)	0.0017 (12)	0.0051 (11)
N1	0.0437 (16)	0.063 (2)	0.0482 (16)	−0.0116 (14)	0.0011 (12)	0.0066 (14)
N2	0.0613 (18)	0.0428 (16)	0.0377 (15)	−0.0034 (14)	0.0069 (13)	0.0029 (13)
C1	0.062 (2)	0.0389 (19)	0.059 (2)	0.0016 (17)	−0.0042 (18)	0.0020 (17)
C2	0.060 (2)	0.051 (2)	0.0407 (19)	0.0009 (17)	0.0009 (16)	−0.0010 (16)
C3	0.052 (2)	0.047 (2)	0.048 (2)	0.0031 (16)	0.0121 (15)	−0.0020 (16)
C4	0.0494 (18)	0.0310 (17)	0.0407 (18)	0.0001 (14)	0.0049 (14)	0.0033 (13)
C5	0.053 (2)	0.050 (2)	0.050 (2)	−0.0008 (17)	0.0153 (16)	−0.0027 (17)
C6	0.052 (2)	0.047 (2)	0.072 (3)	−0.0026 (17)	0.0166 (18)	−0.0060 (19)
C7	0.0502 (19)	0.0400 (18)	0.0409 (19)	0.0065 (15)	0.0139 (15)	−0.0044 (15)

Geometric parameters (Å, º)

Cl—C1	1.741 (4)	C2—C3	1.368 (5)
O1—N2	1.428 (4)	C2—H2B	0.9300
O1—H1C	0.8200	C3—C4	1.402 (5)
N1—C7	1.362 (4)	C3—H3A	0.9300
N1—H1A	0.8600	C4—C5	1.401 (5)
N1—H1B	0.8600	C4—C7	1.458 (5)
N2—C7	1.285 (4)	C5—C6	1.369 (5)
C1—C2	1.361 (5)	C5—H5A	0.9300
C1—C6	1.390 (5)	C6—H6A	0.9300
N2—O1—H1C	109.5	C4—C3—H3A	118.8
C7—N1—H1A	120.0	C5—C4—C3	116.9 (3)
C7—N1—H1B	120.0	C5—C4—C7	121.3 (3)
H1A—N1—H1B	120.0	C3—C4—C7	121.8 (3)
C7—N2—O1	110.0 (3)	C6—C5—C4	121.1 (3)
C2—C1—C6	121.2 (3)	C6—C5—H5A	119.5
C2—C1—Cl	119.3 (3)	C4—C5—H5A	119.5
C6—C1—Cl	119.5 (3)	C5—C6—C1	119.6 (4)
C1—C2—C3	118.9 (3)	C5—C6—H6A	120.2
C1—C2—H2B	120.6	C1—C6—H6A	120.2
C3—C2—H2B	120.6	N2—C7—N1	124.2 (3)
C2—C3—C4	122.4 (3)	N2—C7—C4	118.0 (3)
C2—C3—H3A	118.8	N1—C7—C4	117.7 (3)
C6—C1—C2—C3	−0.8 (5)	C2—C1—C6—C5	0.9 (5)
Cl—C1—C2—C3	179.4 (3)	Cl—C1—C6—C5	−179.3 (3)
C1—C2—C3—C4	0.0 (5)	O1—N2—C7—N1	4.4 (4)
C2—C3—C4—C5	0.6 (5)	O1—N2—C7—C4	−177.9 (3)
C2—C3—C4—C7	179.4 (3)	C5—C4—C7—N2	38.0 (5)
C3—C4—C5—C6	−0.5 (5)	C3—C4—C7—N2	−140.7 (3)
C7—C4—C5—C6	−179.3 (3)	C5—C4—C7—N1	−144.2 (3)
C4—C5—C6—C1	−0.2 (5)	C3—C4—C7—N1	37.1 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1C···N2^i	0.82	2.10	2.756 (4)	136
N1—H1B···O1^ii	0.86	2.43	3.130 (4)	140
N1—H1A···O1	0.86	2.24	2.551 (4)	101

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