(E)-3-Chloro-N′-hy­droxy­benzene-1-carboximidamide

Sreenivasa, S.; ManojKumar, K.E.; Suchetan, P.A.; Mohan, N.R.; Palakshamurthy, B.S.

doi:10.1107/S1600536812046612

organic compounds

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ISSN: 2056-9890

Volume 68| Part 12| December 2012| Page o3402

doi:10.1107/S1600536812046612

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(E)-3-Chloro-N′-hydroxybenzene-1-carboximidamide

S. Sreenivasa,^a ^* K. E. ManojKumar,^a P. A. Suchetan,^b N. R Mohan ^a and B. S. Palakshamurthy ^c

^aDepartment of Studies and Research in Chemistry, Tumkur University, Tumkur, Karnataka 572 103, India, ^bDepartment of Studies and Research in Chemistry, U.C.S, Tumkur University, Tumkur, Karnataka 572 103, India, and ^cDepartment of Studies and Research in Physics, U.C.S., Tumkur University, Tumkur, Karnataka 572 103, India
^*Correspondence e-mail: drsreenivasa@yahoo.co.in

(Received 6 November 2012; accepted 12 November 2012; online 24 November 2012)

The title compound, C₇H₇ClN₂O, crystallizes with two independent molecules in the asymmetric unit. The compound adopts an E configuration across the C=N double bond, as the –OH group and the benzene ring are on opposite sides of the double bond while the H atom of the hydroxy group is directed away from the –NH₂ group. In the crystal, molecules are linked to one another through O—H⋯N and N—H⋯O hydrogen bonds, forming chains along [010].

Related literature

For related syntheses and the biological activity of oxadiazoles, see: Kundu et al. (2012 ); Sakamoto et al. (2007 ); Tyrkov & Sukhenko (2004 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₇H₇ClN₂O
M_r = 170.60
Triclinic, $[P \overline 1]$
a = 5.0018 (17) Å
b = 10.984 (4) Å
c = 14.407 (6) Å
α = 74.000 (12)°
β = 89.952 (12)°
γ = 89.877 (11)°
V = 760.9 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.44 mm⁻¹
T = 298 K
0.24 × 0.22 × 0.20 mm

Data collection

Bruker SMART X2S diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.902, T_max = 0.917
14972 measured reflections
2655 independent reflections
2192 reflections with I > 2σ(I)
R_int = 0.060

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.109
S = 1.05
2655 reflections
218 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2A⋯N4ⁱ	0.82	2.09	2.811 (2)	147
N3—H3B⋯O1ⁱⁱ	0.92 (3)	2.32 (3)	3.006 (2)	131 (2)
O1—H1⋯N2ⁱⁱⁱ	0.82	2.08	2.805 (2)	147
N1—H1B⋯O2^iv	0.87 (3)	2.36 (3)	3.006 (3)	132 (3)
Symmetry codes: (i) -x+2, -y+1, -z; (ii) -x, -y+1, -z; (iii) -x-1, -y+2, -z; (iv) -x+1, -y+1, -z.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: APEX2 and SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812046612/jj2159sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812046612/jj2159Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812046612/jj2159Isup3.cml

checkCIF report

Comment top

Substituted N'-hydroxybenzamidines is a key intermediate obtained during the synthesis of pharmaceutically important 1,2,4-oxadiazole derivatives. 1,2,4-Oxadiazole derivatives are well known for their anti-HIV and anti-microbial activities (Kundu et al., 2012; Sakamoto et al., 2007; Tyrkov et al., 2004). In our studies on these types of compounds, we synthesized the title compound,C₇H₇ClN₂O, (I) and report here its crystal structure.

The title compound, (I), crystallizes with two independent molecules (A & B) in the asymmetric unit (Fig. 1). The compound prefers an E configuration across the C—N double bond, as the OH group and the benzene ring are on opposite sides of the double bond while the hydrogen atom of the hydroxyl group is directed away from the NH₂ group. In the crystal, the independent molecules (A & B) are connected to their respective crystallographically identical molecules through O1—H1···N2 and O2—H2···N4 intermolecular hydrogen bonds, each forming R₂²(6) dimeric pairs (Fig 2). The dimeric pairs are further connected to one another through intermolecular N1-H1N1···O2 and N3-H3N3···O1 hydrogen bonds forming a chain of ring patterns (Bernstein et al., 1995) along [010] (Fig 2).

Related literature top

For related syntheses and the biological activy of oxadiazoles, see: Kundu et al. (2012); Sakamoto et al. (2007); Tyrkov & Sukhenko (2004). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

To a solution of 3-chlorobenzonitrile (1 mmol) in ethanol was added triethyl amine (2.5 mmol) and NH₂OH.HCl (3.5 mmol). The reaction mixture was stirred at room temperature for 12hrs. (The reaction was monitored by TLC). The solvent was removed and the crude product was purified by column chromatography using hexane and ethyl acetate as the eluent. Single crystals required for X-ray diffraction measurements were obtained from slow evaporation of the solution of the compound in a mixture of ethanol and dichloromethane (1:4).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular structure of the title compound, showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Molecular packing of the title compound when viewed along the a axis. O—H···N and N—H···O hydrogen bonds are shown as dashed lines. Hydrogen atoms not involved in hydrogen bonding are omitted for clarity.

(E)-3-chloro-N'-hydroxybenzamidine top

Crystal data top

C₇H₇ClN₂O	F(000) = 352
M_r = 170.60	Prism
Triclinic, P1	D_x = 1.489 Mg m⁻³
Hall symbol: -P 1	Melting point: 386 K
a = 5.0018 (17) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.984 (4) Å	Cell parameters from 218 reflections
c = 14.407 (6) Å	θ = 1.9–25°
α = 74.000 (12)°	µ = 0.44 mm⁻¹
β = 89.952 (12)°	T = 298 K
γ = 89.877 (11)°	Prism, colourless
V = 760.9 (5) Å³	0.24 × 0.22 × 0.20 mm
Z = 4

Data collection top

Bruker SMART X2S diffractometer	2655 independent reflections
Radiation source: fine-focus sealed tube	2192 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.060
Detector resolution: 1.20 pixels mm^-1	θ_max = 25.0°, θ_min = 1.9°
phi and ω scans	h = −5→5
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	k = −13→13
T_min = 0.902, T_max = 0.917	l = −17→17
14972 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 atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.109	w = 1/[σ²(F_o²) + (0.0546P)² + 0.1852P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.001
2655 reflections	Δρ_max = 0.19 e Å⁻³
218 parameters	Δρ_min = −0.24 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 constraints	Extinction coefficient: 0.024 (4)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₇H₇ClN₂O	γ = 89.877 (11)°
M_r = 170.60	V = 760.9 (5) Å³
Triclinic, P1	Z = 4
a = 5.0018 (17) Å	Mo Kα radiation
b = 10.984 (4) Å	µ = 0.44 mm⁻¹
c = 14.407 (6) Å	T = 298 K
α = 74.000 (12)°	0.24 × 0.22 × 0.20 mm
β = 89.952 (12)°

Data collection top

Bruker SMART X2S diffractometer	2655 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	2192 reflections with I > 2σ(I)
T_min = 0.902, T_max = 0.917	R_int = 0.060
14972 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.109	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.19 e Å⁻³
2655 reflections	Δρ_min = −0.24 e Å⁻³
218 parameters

Special details top

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
H1B	0.079 (5)	0.805 (3)	0.050 (2)	0.066 (8)*
H3B	0.430 (5)	0.301 (3)	0.047 (2)	0.065 (8)*
H3A	0.247 (5)	0.322 (2)	0.1254 (17)	0.043 (6)*
H1A	0.256 (5)	0.823 (2)	0.124 (2)	0.060 (7)*
Cl1	0.42873 (11)	0.85954 (5)	0.44393 (4)	0.0554 (2)
O1	−0.3214 (3)	0.87635 (13)	0.00143 (11)	0.0422 (4)
H1	−0.4285	0.9158	−0.0388	0.063*
N1	0.0928 (3)	0.81988 (15)	0.10588 (14)	0.0382 (4)
N2	−0.3071 (3)	0.93253 (14)	0.08000 (12)	0.0356 (4)
C1	−0.0344 (3)	0.95168 (15)	0.20990 (13)	0.0300 (4)
C2	0.1471 (3)	0.89050 (16)	0.28068 (14)	0.0345 (4)
H2	0.2326	0.8170	0.2763	0.041*
C3	0.1997 (4)	0.93902 (17)	0.35722 (14)	0.0363 (4)
C4	0.0746 (4)	1.04675 (18)	0.36709 (15)	0.0417 (5)
H4	0.1116	1.0783	0.4193	0.050*
C5	−0.1068 (4)	1.10622 (19)	0.29740 (16)	0.0456 (5)
H5	−0.1939	1.1787	0.3030	0.055*
C6	−0.1621 (4)	1.06053 (17)	0.21941 (15)	0.0398 (5)
H6	−0.2849	1.1024	0.1731	0.048*
C7	−0.0862 (3)	0.90061 (15)	0.12633 (13)	0.0285 (4)
Cl2	0.07127 (12)	0.35954 (5)	0.44389 (4)	0.0556 (2)
O2	0.8210 (3)	0.37629 (13)	0.00125 (11)	0.0420 (3)
H2A	0.9256	0.4165	−0.0396	0.063*
N3	0.4070 (4)	0.31958 (15)	0.10577 (14)	0.0381 (4)
N4	0.8071 (3)	0.43247 (15)	0.08013 (12)	0.0357 (4)
C8	0.5338 (3)	0.45141 (15)	0.20995 (13)	0.0298 (4)
C9	0.3535 (4)	0.39047 (16)	0.28028 (14)	0.0350 (4)
H9	0.2684	0.3172	0.2757	0.042*
C10	0.3003 (4)	0.43874 (17)	0.35716 (14)	0.0363 (4)
C11	0.4257 (4)	0.54666 (18)	0.36691 (15)	0.0422 (5)
H11	0.3885	0.5782	0.4192	0.051*
C12	0.6065 (4)	0.60617 (19)	0.29736 (16)	0.0457 (5)
H12	0.6931	0.6786	0.3030	0.055*
C13	0.6620 (4)	0.56053 (17)	0.21931 (15)	0.0396 (5)
H13	0.7845	0.6023	0.1729	0.048*
C14	0.5860 (3)	0.40097 (15)	0.12632 (13)	0.0286 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0630 (4)	0.0547 (3)	0.0467 (4)	0.0016 (2)	−0.0246 (3)	−0.0106 (2)
O1	0.0441 (8)	0.0484 (8)	0.0418 (8)	0.0024 (6)	−0.0111 (6)	−0.0251 (7)
N1	0.0349 (10)	0.0440 (9)	0.0412 (10)	0.0039 (7)	−0.0025 (7)	−0.0210 (8)
N2	0.0357 (9)	0.0405 (8)	0.0357 (9)	0.0016 (6)	−0.0075 (7)	−0.0191 (7)
C1	0.0289 (9)	0.0297 (8)	0.0321 (10)	−0.0037 (6)	−0.0001 (7)	−0.0097 (7)
C2	0.0353 (10)	0.0311 (9)	0.0383 (11)	0.0006 (7)	−0.0048 (8)	−0.0114 (8)
C3	0.0358 (10)	0.0381 (9)	0.0335 (10)	−0.0059 (7)	−0.0049 (8)	−0.0075 (8)
C4	0.0522 (12)	0.0401 (10)	0.0375 (11)	−0.0075 (8)	−0.0013 (9)	−0.0185 (9)
C5	0.0544 (13)	0.0391 (10)	0.0500 (13)	0.0068 (8)	−0.0044 (10)	−0.0233 (9)
C6	0.0418 (11)	0.0377 (10)	0.0417 (11)	0.0078 (8)	−0.0107 (8)	−0.0138 (8)
C7	0.0284 (9)	0.0263 (8)	0.0308 (9)	−0.0042 (6)	0.0003 (7)	−0.0081 (7)
Cl2	0.0633 (4)	0.0552 (3)	0.0465 (4)	−0.0023 (2)	0.0241 (3)	−0.0109 (2)
O2	0.0445 (8)	0.0488 (8)	0.0404 (8)	−0.0033 (6)	0.0107 (6)	−0.0252 (7)
N3	0.0331 (10)	0.0442 (9)	0.0423 (10)	−0.0049 (7)	0.0039 (7)	−0.0211 (8)
N4	0.0347 (9)	0.0411 (8)	0.0367 (9)	−0.0018 (6)	0.0056 (7)	−0.0197 (7)
C8	0.0290 (9)	0.0296 (8)	0.0320 (10)	0.0029 (6)	0.0001 (7)	−0.0103 (7)
C9	0.0351 (10)	0.0313 (9)	0.0401 (11)	−0.0006 (7)	0.0044 (8)	−0.0122 (8)
C10	0.0374 (11)	0.0366 (9)	0.0334 (10)	0.0054 (7)	0.0049 (8)	−0.0074 (8)
C11	0.0538 (13)	0.0404 (10)	0.0366 (11)	0.0076 (8)	0.0004 (9)	−0.0181 (9)
C12	0.0545 (13)	0.0390 (10)	0.0497 (13)	−0.0072 (9)	0.0040 (10)	−0.0225 (9)
C13	0.0423 (11)	0.0373 (10)	0.0420 (12)	−0.0085 (8)	0.0083 (8)	−0.0154 (8)
C14	0.0273 (9)	0.0274 (8)	0.0311 (9)	0.0035 (6)	−0.0005 (7)	−0.0081 (7)

Geometric parameters (Å, º) top

Cl1—C3	1.7412 (19)	Cl2—C10	1.742 (2)
O1—N2	1.433 (2)	O2—N4	1.436 (2)
O1—H1	0.8200	O2—H2A	0.8200
N1—C7	1.347 (2)	N3—C14	1.356 (2)
N1—H1B	0.87 (3)	N3—H3B	0.92 (3)
N1—H1A	0.86 (3)	N3—H3A	0.85 (2)
N2—C7	1.288 (2)	N4—C14	1.288 (2)
C1—C2	1.391 (2)	C8—C9	1.384 (3)
C1—C6	1.394 (3)	C8—C13	1.399 (2)
C1—C7	1.485 (2)	C8—C14	1.481 (2)
C2—C3	1.376 (3)	C9—C10	1.379 (3)
C2—H2	0.9300	C9—H9	0.9300
C3—C4	1.379 (3)	C10—C11	1.383 (3)
C4—C5	1.377 (3)	C11—C12	1.375 (3)
C4—H4	0.9300	C11—H11	0.9300
C5—C6	1.380 (3)	C12—C13	1.379 (3)
C5—H5	0.9300	C12—H12	0.9300
C6—H6	0.9300	C13—H13	0.9300

N2—O1—H1	109.5	N4—O2—H2A	109.5
C7—N1—H1B	116.7 (17)	C14—N3—H3B	116.1 (16)
C7—N1—H1A	118.6 (17)	C14—N3—H3A	117.6 (15)
H1B—N1—H1A	114 (2)	H3B—N3—H3A	117 (2)
C7—N2—O1	109.78 (14)	C14—N4—O2	109.65 (14)
C2—C1—C6	118.65 (17)	C9—C8—C13	118.93 (17)
C2—C1—C7	119.67 (15)	C9—C8—C14	119.71 (15)
C6—C1—C7	121.67 (16)	C13—C8—C14	121.36 (16)
C3—C2—C1	119.83 (17)	C10—C9—C8	119.82 (16)
C3—C2—H2	120.1	C10—C9—H9	120.1
C1—C2—H2	120.1	C8—C9—H9	120.1
C2—C3—C4	121.88 (17)	C9—C10—C11	121.64 (18)
C2—C3—Cl1	118.24 (14)	C9—C10—Cl2	118.40 (14)
C4—C3—Cl1	119.87 (15)	C11—C10—Cl2	119.96 (15)
C5—C4—C3	118.08 (18)	C12—C11—C10	118.32 (18)
C5—C4—H4	121.0	C12—C11—H11	120.8
C3—C4—H4	121.0	C10—C11—H11	120.8
C4—C5—C6	121.40 (18)	C11—C12—C13	121.28 (18)
C4—C5—H5	119.3	C11—C12—H12	119.4
C6—C5—H5	119.3	C13—C12—H12	119.4
C5—C6—C1	120.15 (18)	C12—C13—C8	120.01 (18)
C5—C6—H6	119.9	C12—C13—H13	120.0
C1—C6—H6	119.9	C8—C13—H13	120.0
N2—C7—N1	123.84 (17)	N4—C14—N3	123.71 (17)
N2—C7—C1	117.48 (15)	N4—C14—C8	117.58 (15)
N1—C7—C1	118.61 (16)	N3—C14—C8	118.62 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···N4ⁱ	0.82	2.09	2.811 (2)	147
N3—H3B···O1ⁱⁱ	0.92 (3)	2.32 (3)	3.006 (2)	131 (2)
O1—H1···N2ⁱⁱⁱ	0.82	2.08	2.805 (2)	147
N1—H1B···O2^iv	0.87 (3)	2.36 (3)	3.006 (3)	132 (3)

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

Experimental details

Crystal data
Chemical formula	C₇H₇ClN₂O
M_r	170.60
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	5.0018 (17), 10.984 (4), 14.407 (6)
α, β, γ (°)	74.000 (12), 89.952 (12), 89.877 (11)
V (Å³)	760.9 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.44
Crystal size (mm)	0.24 × 0.22 × 0.20

Data collection
Diffractometer	Bruker SMART X2S diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2004)
T_min, T_max	0.902, 0.917
No. of measured, independent and observed [I > 2σ(I)] reflections	14972, 2655, 2192
R_int	0.060
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.109, 1.05
No. of reflections	2655
No. of parameters	218
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.24

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···N4ⁱ	0.82	2.09	2.811 (2)	147.2
N3—H3B···O1ⁱⁱ	0.92 (3)	2.32 (3)	3.006 (2)	131 (2)
O1—H1···N2ⁱⁱⁱ	0.82	2.08	2.805 (2)	147
N1—H1B···O2^iv	0.87 (3)	2.36 (3)	3.006 (3)	132 (3)

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

Acknowledgements

The authors thank Dr S. C. Sharma, Vice Chancellor, Tumkur University, Tumkur, for his constant encouragement, and Professor T. N. Guru Row and Vijithkumar, S. S. C. U, Indian Institute of Science, Bangalore, for their help with the data collection. They also thank Dr H. C. Devarajegowda, Department of Physics, Yuvarajas College (constituent), University of Mysore, for his support.

References

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