2-Amino-3,5-dichloro­benzohydroxamic acid: supra­molecular aggregation through two-dimensional networks of O—H...N/O and N—H...O/Cl inter­actions

In the crystal structure of the title compound, C₇H₆Cl₂N₂O₂, the dihedral angle between the mean planes of the benzene ring and the hydroxamic acid group is 40.1 (1)°. The mol­ecules are linked via O—H...N/O and N—H...O/Cl hydrogen bonds, forming two-dimensional layers parallel to (100).

Key indicators

• Single-crystal X-ray study
• T = 193 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.039
• wR factor = 0.098
• Data-to-parameter ratio = 14.7

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.89

Author Response: Due to weak high order reflections it was impossible to collect the dataset over the entire theta range

   1 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   0 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
   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

---

Computing details

Data collection: P3/PC (Siemens, 1989); cell refinement: P3/PC; data reduction: P3/PC; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97.

2-Amino-3,5-dichlorobenzohydroxamic acid

Crystal data

C7H6Cl2N2O2	F(000) = 448
Mr = 221.04	Dx = 1.718 Mg m^−3
Monoclinic, P2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yc	Cell parameters from 24 reflections
a = 13.799 (3) Å	θ = 12–13°
b = 4.8292 (10) Å	µ = 0.72 mm^−1
c = 13.206 (3) Å	T = 193 K
β = 103.88 (3)°	Needle, colourless
V = 854.3 (3) Å^3	0.60 × 0.10 × 0.10 mm
Z = 4

Data collection

Rebuilt Syntex P21/Siemens P3 four-circle diffractometer	Rint = 0.020
Radiation source: normal-focus sealed tube	θmax = 28.1°, θmin = 3.0°
Graphite monochromator	h = −18→17
ω/2θ scans	k = −6→0
2178 measured reflections	l = 0→17
2084 independent reflections	2 standard reflections every 98 reflections
1612 reflections with I > 2σ(I)	intensity decay: 1%

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.098	All H-atom parameters refined
S = 1.09	w = 1/[σ^2(Fo^2) + (0.04P)^2 + 0.8P] where P = (Fo^2 + 2Fc^2)/3
2084 reflections	(Δ/σ)max = 0.001
142 parameters	Δρmax = 0.38 e Å^−3
0 restraints	Δρmin = −0.24 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
Cl12	0.58947 (4)	1.10572 (14)	0.68207 (5)	0.03793 (17)
Cl13	0.64365 (4)	0.38707 (12)	0.38951 (5)	0.03515 (16)
O9	0.97389 (12)	1.1934 (3)	0.62876 (14)	0.0314 (4)
O10	1.10303 (12)	0.7783 (4)	0.62800 (15)	0.0353 (4)
N8	1.00028 (13)	0.7431 (4)	0.61073 (16)	0.0268 (4)
N11	0.80851 (16)	1.1995 (4)	0.72374 (15)	0.0271 (4)
C1	0.83152 (15)	0.8866 (4)	0.58539 (15)	0.0200 (4)
C2	0.76984 (15)	1.0194 (4)	0.64141 (15)	0.0213 (4)
C3	0.66891 (15)	0.9454 (5)	0.61612 (17)	0.0252 (4)
C4	0.62936 (16)	0.7528 (5)	0.54009 (17)	0.0274 (5)
C5	0.69214 (16)	0.6279 (4)	0.48631 (16)	0.0249 (4)
C6	0.79268 (16)	0.6936 (4)	0.50809 (16)	0.0232 (4)
C7	0.94036 (15)	0.9556 (4)	0.60893 (15)	0.0210 (4)
H4	0.559 (2)	0.713 (6)	0.523 (2)	0.033 (7)*
H6	0.8322 (19)	0.615 (6)	0.471 (2)	0.031 (7)*
H8	0.982 (2)	0.571 (6)	0.608 (2)	0.033 (7)*
H10	1.117 (2)	0.921 (7)	0.659 (3)	0.050 (9)*
H11A	0.769 (2)	1.290 (7)	0.746 (2)	0.042 (8)*
H11B	0.862 (2)	1.282 (7)	0.718 (2)	0.045 (8)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl12	0.0302 (3)	0.0488 (4)	0.0379 (3)	0.0069 (3)	0.0141 (2)	−0.0029 (3)
Cl13	0.0410 (3)	0.0269 (3)	0.0324 (3)	−0.0099 (2)	−0.0014 (2)	−0.0064 (2)
O9	0.0306 (8)	0.0154 (7)	0.0447 (10)	−0.0035 (6)	0.0021 (7)	−0.0032 (7)
O10	0.0225 (8)	0.0299 (9)	0.0536 (11)	−0.0024 (7)	0.0091 (7)	−0.0173 (8)
N8	0.0240 (9)	0.0170 (9)	0.0410 (11)	−0.0022 (7)	0.0113 (8)	−0.0039 (8)
N11	0.0294 (10)	0.0244 (9)	0.0277 (10)	0.0023 (8)	0.0070 (8)	−0.0061 (8)
C1	0.0237 (9)	0.0155 (8)	0.0204 (9)	−0.0004 (8)	0.0042 (7)	0.0024 (8)
C2	0.0255 (10)	0.0179 (9)	0.0189 (9)	0.0029 (8)	0.0023 (7)	0.0018 (8)
C3	0.0252 (10)	0.0260 (12)	0.0248 (10)	0.0045 (8)	0.0069 (8)	0.0035 (8)
C4	0.0251 (10)	0.0249 (11)	0.0302 (11)	−0.0032 (8)	0.0028 (9)	0.0046 (9)
C5	0.0324 (11)	0.0179 (9)	0.0215 (10)	−0.0042 (8)	0.0010 (8)	0.0005 (8)
C6	0.0309 (11)	0.0165 (9)	0.0223 (10)	−0.0013 (8)	0.0067 (8)	−0.0009 (8)
C7	0.0267 (10)	0.0172 (9)	0.0191 (9)	−0.0023 (8)	0.0055 (8)	0.0005 (7)

Geometric parameters (Å, º)

Cl12—C3	1.737 (2)	C1—C6	1.391 (3)
Cl13—C5	1.739 (2)	C1—C2	1.409 (3)
O9—C7	1.242 (3)	C1—C7	1.496 (3)
O10—N8	1.391 (2)	C2—C3	1.399 (3)
O10—H10	0.80 (3)	C3—C4	1.381 (3)
N8—C7	1.314 (3)	C4—C5	1.383 (3)
N8—H8	0.87 (3)	C4—H4	0.96 (3)
N11—C2	1.394 (3)	C5—C6	1.384 (3)
N11—H11A	0.81 (3)	C6—H6	0.90 (3)
N11—H11B	0.85 (3)
N8—O10—H10	108 (2)	C4—C3—Cl12	118.54 (17)
C7—N8—O10	121.31 (18)	C2—C3—Cl12	118.58 (17)
C7—N8—H8	124.5 (18)	C3—C4—C5	118.7 (2)
O10—N8—H8	113.8 (18)	C3—C4—H4	120.6 (16)
C2—N11—H11A	117 (2)	C5—C4—H4	120.7 (16)
C2—N11—H11B	113 (2)	C4—C5—C6	120.9 (2)
H11A—N11—H11B	117 (3)	C4—C5—Cl13	119.41 (17)
C6—C1—C2	121.02 (19)	C6—C5—Cl13	119.71 (17)
C6—C1—C7	119.50 (19)	C5—C6—C1	119.8 (2)
C2—C1—C7	119.48 (18)	C5—C6—H6	119.9 (17)
N11—C2—C3	121.23 (19)	C1—C6—H6	120.3 (17)
N11—C2—C1	121.80 (19)	O9—C7—N8	121.13 (19)
C3—C2—C1	116.78 (19)	O9—C7—C1	123.65 (19)
C4—C3—C2	122.9 (2)	N8—C7—C1	115.19 (18)
C6—C1—C2—N11	175.7 (2)	C3—C4—C5—Cl13	−179.45 (17)
C7—C1—C2—N11	−4.7 (3)	C4—C5—C6—C1	0.3 (3)
C6—C1—C2—C3	0.6 (3)	Cl13—C5—C6—C1	179.89 (16)
C7—C1—C2—C3	−179.76 (18)	C2—C1—C6—C5	−0.7 (3)
N11—C2—C3—C4	−175.3 (2)	C7—C1—C6—C5	179.69 (18)
C1—C2—C3—C4	−0.2 (3)	O10—N8—C7—O9	−4.3 (3)
N11—C2—C3—Cl12	5.5 (3)	O10—N8—C7—C1	177.72 (19)
C1—C2—C3—Cl12	−179.38 (15)	C6—C1—C7—O9	140.6 (2)
C2—C3—C4—C5	−0.2 (3)	C2—C1—C7—O9	−39.0 (3)
Cl12—C3—C4—C5	179.01 (17)	C6—C1—C7—N8	−41.6 (3)
C3—C4—C5—C6	0.1 (3)	C2—C1—C7—N8	138.8 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N8—H8···O9^i	0.87 (3)	1.85 (3)	2.698 (2)	165 (3)
N11—H11A···Cl12	0.81 (3)	2.58 (3)	2.974 (2)	112 (3)
N11—H11B···O9	0.85 (3)	2.20 (3)	2.856 (3)	133 (3)
O10—H10···O9	0.80 (3)	2.33 (3)	2.684 (2)	108 (3)
O10—H10···N11^ii	0.80 (3)	2.12 (3)	2.884 (3)	159 (3)
C6—H6···O10^iii	0.90 (3)	2.58 (3)	3.426 (3)	156 (2)

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