4-Methoxy­anilinium chloride

Abstract

The crystal structure of the title compound, C₇H₁₀NO⁺·Cl⁻, was synthesized by the reaction of 4-methoxy­aniline and hydro­chloric acid. In the crystal structure, the ions are involved in inter­molecular N—H⋯Cl hydrogen bonds.

Related literature

For a similar organic acid-base product, see: Wu et al. (2006 ▶). This work is part of a systematic investigation of dielectric–ferroelectric materials, including organic ligands, metal–organic coordination compounds and organic–inorganic hybrid materials; see: Li et al. (2008 ▶); Hang et al. (2009 ▶).

Experimental

Crystal data

• C₇H₁₀NO⁺·Cl⁻

• M _r = 159.61

• Orthorhombic,

• a = 8.905 (2) Å

• b = 8.489 (2) Å

• c = 21.817 (4) Å

• V = 1649.3 (6) ų

• Z = 8

• Mo Kα radiation

• μ = 0.40 mm⁻¹

• T = 298 K

• 0.20 × 0.20 × 0.20 mm

Data collection

• Rigaku SCXmini diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ▶) T _min = 0.924, T _max = 0.924

• 15436 measured reflections

• 1886 independent reflections

• 1452 reflections with I > 2σ(I)

• R _int = 0.058

Refinement

• R[F ² > 2σ(F ²)] = 0.062

• wR(F ²) = 0.165

• S = 1.12

• 1886 reflections

• 91 parameters

• H-atom parameters constrained

• Δρ_max = 0.25 e Å⁻³

• Δρ_min = −0.54 e Å⁻³

Data collection: CrystalClear (Rigaku, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; 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: PRPKAPPA (Ferguson, 1999 ▶).

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1D⋯Cl1i	0.89	2.47	3.360 (3)	179
N1—H1E⋯Cl1ii	0.89	2.50	3.209 (2)	137
N1—H1F⋯Cl1iii	0.89	2.38	3.167 (2)	147

Symmetry codes: (i) ; (ii) ; (iii) .

supplementary crystallographic information

Comment

Acid-base reactions of organic reactands were already widely researched by ancient chemists (Wu et al., 2006). This study is a part of a systematic investigation of dielectric-ferroelectric materials, including organic ligands, metal-organic coordination compounds and organic-inorganic hybrid materials (Li et al., 2008; Hang et al., 2009). Nevertheless, 4-methoxy-anilinium chloride shows no dielectric irregularity in the temperature range of 80 K to 400 K, (m.p. 401 K).

The asymmetric unit of the title compound is composed of cationic (CH₃O–C₆H₄–NH₃⁺) and chloride anions (Fig 1). Intramolecular hydrogen bonds between the ammonium groups of the organic cations and the chloride anions are observed in the crystal structure.

Experimental

Single crystals of 4-methoxy-anilinium chloride are prepared by slow evaporation at room temperature of 20 mL of an ethanolic solution of 4-methoxyphenylamine and an excess of hydrogen chloride (6 mol/L).

Refinement

All hydrogen atoms were calculated geometrically with C—H distances of 0.93 Å for aromatic C–H functions, 0.96 Å for the methyl group and 0.89 Å for the ammonium substituent. All hydrogen atoms were allowed to ride on the C and N atoms to which they are bonded with thermal parameters of U_iso(H) = 1.2Ueq(parent atom).

Figures

Fig. 1.

The molecular structure of the title compound showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

Fig. 2.

View of the packing of the title compound, stacking along the a axis. Dashed lines indicate hydrogen bonds.

Crystal data

C7H10NO+·Cl−	F(000) = 672
Mr = 159.61	Dx = 1.286 Mg m−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 6458 reflections
a = 8.905 (2) Å	θ = 3.0–27.6°
b = 8.489 (2) Å	µ = 0.40 mm−1
c = 21.817 (4) Å	T = 298 K
V = 1649.3 (6) Å3	Prism, colourless
Z = 8	0.20 × 0.20 × 0.20 mm

Data collection

Rigaku SCXmini diffractometer	1886 independent reflections
Radiation source: fine-focus sealed tube	1452 reflections with I > 2σ(I)
graphite	Rint = 0.058
Detector resolution: 13.6612 pixels mm-1	θmax = 27.5°, θmin = 3.4°
ω scans	h = −11→11
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −10→11
Tmin = 0.924, Tmax = 0.924	l = −27→28
15436 measured reflections

Refinement

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.062	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.165	H-atom parameters constrained
S = 1.12	w = 1/[σ2(Fo2) + (0.0824P)2 + 0.5018P] where P = (Fo2 + 2Fc2)/3
1886 reflections	(Δ/σ)max < 0.001
91 parameters	Δρmax = 0.25 e Å−3
0 restraints	Δρmin = −0.53 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
Cl1	0.75138 (6)	0.98509 (7)	0.52111 (3)	0.0470 (3)
O1	0.1534 (2)	0.1996 (2)	0.29469 (8)	0.0623 (6)
N1	0.0252 (3)	0.2494 (3)	0.04478 (10)	0.0617 (7)
H1D	−0.0468	0.3203	0.0383	0.093*
H1E	−0.0059	0.1553	0.0320	0.093*
H1F	0.1073	0.2770	0.0242	0.093*
C2	0.1175 (3)	0.2222 (3)	0.23454 (10)	0.0438 (6)
C5	0.0595 (3)	0.2423 (3)	0.11049 (11)	0.0441 (6)
C4	0.1677 (3)	0.1392 (3)	0.13138 (12)	0.0561 (7)
H4A	0.2203	0.0762	0.1039	0.067*
C6	−0.0179 (3)	0.3363 (3)	0.15081 (12)	0.0492 (6)
H6A	−0.0895	0.4069	0.1363	0.059*
C7	0.0108 (3)	0.3259 (3)	0.21326 (11)	0.0472 (6)
H7A	−0.0420	0.3890	0.2407	0.057*
C3	0.1970 (3)	0.1303 (4)	0.19295 (13)	0.0575 (7)
H3A	0.2710	0.0621	0.2071	0.069*
C1	0.0870 (4)	0.3025 (4)	0.33900 (13)	0.0761 (10)
H1A	0.1211	0.2740	0.3792	0.114*
H1B	−0.0203	0.2934	0.3371	0.114*
H1C	0.1157	0.4092	0.3304	0.114*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.0461 (4)	0.0472 (4)	0.0478 (4)	−0.0017 (2)	0.0013 (3)	−0.0042 (2)
O1	0.0691 (13)	0.0735 (13)	0.0442 (10)	−0.0047 (11)	−0.0113 (9)	0.0042 (9)
N1	0.0690 (16)	0.0723 (16)	0.0439 (12)	−0.0200 (12)	−0.0091 (11)	0.0082 (11)
C2	0.0435 (14)	0.0466 (12)	0.0414 (13)	−0.0109 (11)	−0.0051 (10)	0.0065 (10)
C5	0.0440 (13)	0.0496 (13)	0.0388 (12)	−0.0143 (11)	−0.0040 (10)	0.0055 (10)
C4	0.0598 (16)	0.0597 (16)	0.0488 (15)	0.0083 (13)	0.0060 (12)	−0.0031 (12)
C6	0.0421 (13)	0.0499 (14)	0.0554 (14)	0.0024 (11)	−0.0056 (11)	0.0060 (12)
C7	0.0404 (13)	0.0526 (15)	0.0486 (13)	−0.0008 (11)	0.0000 (11)	−0.0056 (11)
C3	0.0570 (16)	0.0592 (16)	0.0564 (16)	0.0167 (14)	−0.0053 (13)	0.0062 (13)
C1	0.075 (2)	0.109 (3)	0.0448 (15)	−0.011 (2)	−0.0045 (14)	−0.0147 (16)

Geometric parameters (Å, °)

O1—C2	1.364 (3)	C4—C3	1.370 (4)
O1—C1	1.431 (4)	C4—H4A	0.9300
N1—C5	1.467 (3)	C6—C7	1.389 (4)
N1—H1D	0.8900	C6—H6A	0.9300
N1—H1E	0.8900	C7—H7A	0.9300
N1—H1F	0.8900	C3—H3A	0.9300
C2—C7	1.376 (4)	C1—H1A	0.9600
C2—C3	1.390 (4)	C1—H1B	0.9600
C5—C6	1.373 (4)	C1—H1C	0.9600
C5—C4	1.380 (4)
C2—O1—C1	117.9 (2)	C5—C6—C7	119.9 (2)
C5—N1—H1D	109.5	C5—C6—H6A	120.0
C5—N1—H1E	109.5	C7—C6—H6A	120.0
H1D—N1—H1E	109.5	C2—C7—C6	119.9 (2)
C5—N1—H1F	109.5	C2—C7—H7A	120.0
H1D—N1—H1F	109.5	C6—C7—H7A	120.0
H1E—N1—H1F	109.5	C4—C3—C2	120.8 (2)
O1—C2—C7	125.2 (2)	C4—C3—H3A	119.6
O1—C2—C3	115.4 (2)	C2—C3—H3A	119.6
C7—C2—C3	119.4 (2)	O1—C1—H1A	109.5
C6—C5—C4	120.5 (2)	O1—C1—H1B	109.5
C6—C5—N1	119.8 (2)	H1A—C1—H1B	109.5
C4—C5—N1	119.6 (2)	O1—C1—H1C	109.5
C3—C4—C5	119.5 (2)	H1A—C1—H1C	109.5
C3—C4—H4A	120.3	H1B—C1—H1C	109.5
C5—C4—H4A	120.3
C1—O1—C2—C7	−6.9 (4)	O1—C2—C7—C6	−178.8 (2)
C1—O1—C2—C3	173.4 (3)	C3—C2—C7—C6	0.9 (4)
C6—C5—C4—C3	0.4 (4)	C5—C6—C7—C2	0.4 (4)
N1—C5—C4—C3	−178.5 (2)	C5—C4—C3—C2	1.0 (4)
C4—C5—C6—C7	−1.1 (4)	O1—C2—C3—C4	178.1 (3)
N1—C5—C6—C7	177.8 (2)	C7—C2—C3—C4	−1.6 (4)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1D···Cl1i	0.89	2.47	3.360 (3)	179
N1—H1E···Cl1ii	0.89	2.50	3.209 (2)	137
N1—H1F···Cl1iii	0.89	2.38	3.167 (2)	147

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