Crystal structure of 4-amino-2,6-di­chloro­phenol

Abstract

The title compound, C₆H₅Cl₂NO, has a single planar mol­ecule in the asymmetric unit with the non-H atoms possessing a mean deviation from planarity of 0.020 Å. In the crystal, O—H⋯N hydrogen bonds lead to the formation of infinite chains along [101] which are further linked by N—H⋯O hydrogen bonds, forming (010) sheets.

Related literature  

For the crystal structure of the parent p-amino­phenol, see: Brown (1951 ▸). For other related structures, see: Ermer & Eling (1994 ▸); Dey et al. (2005 ▸); Bacchi et al. (2009 ▸).

Experimental  

Crystal data  

• C₆H₅Cl₂NO

• M _r = 178.02

• Monoclinic,

• a = 4.6064 (5) Å

• b = 11.7569 (12) Å

• c = 13.2291 (13) Å

• β = 96.760 (5)°

• V = 711.47 (13) ų

• Z = 4

• Cu Kα radiation

• μ = 7.59 mm⁻¹

• T = 120 K

• 0.4 × 0.2 × 0.1 mm

Data collection  

• Bruker D8 Venture CMOS diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2014 ▸) T _min = 0.425, T _max = 0.754

• 7481 measured reflections

• 1402 independent reflections

• 1273 reflections with I ≥ 2σ(I)

• R _int = 0.043

Refinement  

• R[F ² > 2σ(F ²)] = 0.033

• wR(F ²) = 0.091

• S = 1.05

• 1402 reflections

• 99 parameters

• 2 restraints

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.33 e Å⁻³

• Δρ_min = −0.35 e Å⁻³

Data collection: APEX2 (Bruker, 2014 ▸); cell refinement: SAINT (Bruker, 2014 ▸); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015 ▸) and OLEX2.refine (Bourhis et al., 2015 ▸); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▸); software used to prepare material for publication: OLEX2 and publCIF (Westrip, 2010 ▸).

Supplementary Material

CCDC reference: 1400729

Additional supporting information: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (, ).

DHA	DH	HA	D A	DHA
O1H1N1i	0.85(2)	1.82(2)	2.653(2)	168(2)
N1H1aO1ii	0.87(1)	2.05(1)	2.921(2)	177(2)

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

S1. Comment

The hydrogen bonding networks of amino­phenols have been explored as hy­droxy and amino groups are complementary hydrogen bonding donors and acceptors. This is exemplified in p-amino­phenol, which exhibits a supertetra­hedral hydrogen bonded architecture where all hydrogen bonding donors and acceptors are saturated (Brown, 1951; Ermer et al., 1994). The mono-substitution in 4-amino-2-methyl­phenol and 4-amino-3-methyl­phenol yields a square motif structure that again exhibits saturation among hydrogen bonding donors and acceptors (Dey et al., 2005). The more sterically encumbered substitution of 4-amino-2,6-di­phenyl­phenol prevents the saturation in hydrogen bonding, with only O–H···N and N–H···aryl inter­actions observed (Bacchi et al., 2009). The 2,6-di­chloro substitution of the title compound also prevents saturation in its hydrogen bonding network.

The molecular structure of the title compound demonstrates a planar molecule with a mean deviation from the plane of the non-hydrogen atoms of 0.020 Å. Inter­molecular hydrogen bonding between O1–H1···N1 results in infinite chains along [101] which combine with inter­molecular hydrogen bonding between N1–H1a···O1 to give (010) sheets. The packing for the title compound indicating hydrogen bonding is shown in Figure 2.

S2. Experimental

A commercial sample (Aldrich) was used for the crystallization. Crystals suitable for single crystal X-ray analysis were grown by slow evaporation of a methanol solution.

S3. Refinement

All non-hydrogen atoms were refined anisotropically (Olex2) by full matrix least squares on F². Hydrogen atoms H1, H1a and H1b were found from a Fourier difference map. H1 was allowed to refine freely with an isotropic displacement parameter of 1.20 times U_eq of the parent O atom. H1a and H1b were refined with a fixed distance of 0.87 (0.005) Å and isotropic displacement parameters of 1.20 times U_eq of the parent N atom. The two remaining hydrogen atoms were placed in calculated positions and then refined with riding model with C–H lengths of 0.95 Å with isotropic displacement parameters set to 1.20 times U_eq of the parent C atom.

Figures

Fig. 1.

Molecular structure of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are drawn as spheres of arbitrary radius.

Fig. 2.

Molecular packing of the title compound with hydrogen bonding shown as dashed lines.

Crystal data

C6H5Cl2NO	F(000) = 363.7579
Mr = 178.02	Dx = 1.662 Mg m−3
Monoclinic, P21/n	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2yn	Cell parameters from 5198 reflections
a = 4.6064 (5) Å	θ = 5.1–72.2°
b = 11.7569 (12) Å	µ = 7.59 mm−1
c = 13.2291 (13) Å	T = 120 K
β = 96.760 (5)°	Plate, colourless
V = 711.47 (13) Å3	0.4 × 0.2 × 0.1 mm
Z = 4

Data collection

Bruker D8 Venture CMOS diffractometer	1402 independent reflections
Radiation source: microfocus Cu	1273 reflections with I≥ 2σ(I)
HELIOS MX monochromator	Rint = 0.043
Detector resolution: 102.4 pixels mm-1	θmax = 72.2°, θmin = 5.1°
φ and ω scans	h = −5→5
Absorption correction: multi-scan (SADABS; Bruker, 2014)	k = −14→14
Tmin = 0.425, Tmax = 0.754	l = −12→16
7481 measured reflections

Refinement

Refinement on F2	2 restraints
Least-squares matrix: full	7 constraints
R[F2 > 2σ(F2)] = 0.033	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.091	w = 1/[σ2(Fo2) + (0.0618P)2 + 0.1912P] where P = (Fo2 + 2Fc2)/3
S = 1.05	(Δ/σ)max < 0.001
1402 reflections	Δρmax = 0.33 e Å−3
99 parameters	Δρmin = −0.35 e Å−3

Special details

Experimental. Absorption correction: SADABS-2014/4 (Bruker, 2014) was used for absorption correction. wR2(int) was 0.1370 before and 0.0641 after correction. The Ratio of minimum to maximum transmission is 0.5642. The λ/2 correction factor is 0.00150.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.10618 (10)	0.09750 (4)	0.70434 (3)	0.02213 (17)
Cl2	0.79187 (11)	0.44532 (4)	0.61176 (4)	0.02666 (18)
O1	0.4519 (3)	0.30303 (12)	0.74687 (10)	0.0214 (3)
N1	0.4522 (4)	0.13356 (14)	0.35171 (12)	0.0199 (4)
C1	0.4563 (4)	0.26523 (16)	0.65055 (14)	0.0176 (4)
C4	0.4607 (4)	0.17796 (16)	0.45234 (13)	0.0176 (4)
C5	0.6112 (4)	0.27756 (16)	0.48060 (14)	0.0196 (4)
H5	0.7170 (4)	0.31620 (16)	0.43359 (14)	0.0235 (5)*
C2	0.3011 (4)	0.16753 (16)	0.61822 (14)	0.0171 (4)
C3	0.3014 (4)	0.12337 (16)	0.52110 (14)	0.0182 (4)
H3	0.1938 (4)	0.05638 (16)	0.50165 (14)	0.0219 (5)*
C6	0.6052 (4)	0.31990 (16)	0.57788 (14)	0.0179 (4)
H1	0.615 (5)	0.329 (2)	0.7732 (18)	0.0215 (5)*
H1a	0.601 (3)	0.1551 (19)	0.3217 (15)	0.0215 (5)*
H1b	0.451 (5)	0.0598 (4)	0.3523 (17)	0.0215 (5)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.0232 (3)	0.0246 (3)	0.0204 (3)	−0.00409 (16)	0.00988 (19)	0.00083 (17)
Cl2	0.0334 (3)	0.0245 (3)	0.0225 (3)	−0.01014 (19)	0.0052 (2)	−0.00026 (18)
O1	0.0193 (6)	0.0298 (7)	0.0156 (7)	−0.0039 (6)	0.0046 (5)	−0.0042 (6)
N1	0.0206 (8)	0.0247 (9)	0.0151 (8)	0.0013 (6)	0.0057 (6)	−0.0009 (6)
C1	0.0146 (8)	0.0225 (9)	0.0159 (9)	0.0027 (7)	0.0023 (7)	0.0008 (7)
C4	0.0138 (8)	0.0248 (9)	0.0142 (9)	0.0050 (7)	0.0009 (7)	0.0005 (7)
C5	0.0177 (9)	0.0244 (10)	0.0173 (9)	0.0005 (7)	0.0048 (7)	0.0054 (7)
C2	0.0144 (8)	0.0215 (9)	0.0163 (9)	0.0011 (7)	0.0051 (7)	0.0035 (7)
C3	0.0148 (8)	0.0217 (9)	0.0185 (10)	0.0005 (7)	0.0029 (7)	−0.0007 (7)
C6	0.0158 (8)	0.0188 (9)	0.0194 (9)	−0.0007 (7)	0.0026 (7)	0.0016 (7)

Geometric parameters (Å, º)

Cl1—C2	1.7387 (18)	C1—C6	1.401 (3)
Cl2—C6	1.7389 (19)	C4—C5	1.389 (3)
O1—C1	1.352 (2)	C4—C3	1.391 (3)
O1—H1	0.85 (2)	C5—H5	0.9500
N1—C4	1.426 (2)	C5—C6	1.383 (3)
N1—H1a	0.870 (5)	C2—C3	1.386 (3)
N1—H1b	0.867 (5)	C3—H3	0.9500
C1—C2	1.393 (3)
H1—O1—C1	113.3 (16)	C6—C5—C4	119.33 (17)
H1a—N1—C4	112.6 (15)	C6—C5—H5	120.34 (11)
H1b—N1—C4	110.9 (15)	C1—C2—Cl1	118.37 (14)
H1b—N1—H1a	108 (2)	C3—C2—Cl1	119.15 (14)
C2—C1—O1	119.75 (16)	C3—C2—C1	122.47 (16)
C6—C1—O1	123.97 (17)	C2—C3—C4	119.44 (18)
C6—C1—C2	116.26 (17)	H3—C3—C4	120.28 (11)
C5—C4—N1	121.18 (17)	H3—C3—C2	120.28 (11)
C3—C4—N1	118.87 (18)	C1—C6—Cl2	118.64 (14)
C3—C4—C5	119.85 (17)	C5—C6—Cl2	118.79 (14)
H5—C5—C4	120.34 (10)	C5—C6—C1	122.57 (17)
Cl1—C2—C3—C4	−178.98 (14)	C4—C5—C6—Cl2	−179.43 (14)
O1—C1—C2—Cl1	−0.1 (2)	C4—C5—C6—C1	1.0 (3)
O1—C1—C2—C3	−178.74 (17)	C5—C4—C3—C2	−1.7 (3)
O1—C1—C6—Cl2	−1.1 (3)	C2—C1—C6—Cl2	177.57 (13)
O1—C1—C6—C5	178.43 (17)	C2—C1—C6—C5	−2.9 (3)
N1—C4—C5—C6	177.70 (17)	C3—C4—C5—C6	1.3 (3)
N1—C4—C3—C2	−178.14 (17)	C6—C1—C2—Cl1	−178.80 (13)
C1—C2—C3—C4	−0.3 (3)	C6—C1—C2—C3	2.5 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1i	0.85 (2)	1.82 (2)	2.653 (2)	168 (2)
N1—H1a···O1ii	0.87 (1)	2.05 (1)	2.921 (2)	177 (2)

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