Methyl 4-amino-3-methyl­benzoate

Li, X.; Yuan, L.-S.; Wang, D.; Liu, S.; Yao, C.

doi:10.1107/S1600536808006223

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 64| Part 5| May 2008| Page o886

doi:10.1107/S1600536808006223

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Methyl 4-amino-3-methylbenzoate

Xiang Li,^a Lian-Shan Yuan,^a Dan Wang,^b Shan Liu ^a and Cheng Yao ^a ^*

^aDepartment of Applied Chemistry, College of Sciences, Nanjing University of Technolgy, Xinmofan Road No. 5, Nanjing 210009, People's Republic of China, and ^bBioengineering Department, Xuzhou Higher Vocational College of Bioengineering, Mine West Road, Xuzhou 221006, People's Republic of China
^*Correspondence e-mail: yaocheng@njut.edu.cn

(Received 3 March 2008; accepted 6 March 2008; online 23 April 2008)

In the molecule of the title compound, C₉H₁₁NO₂, the methyl C and amino N atoms bonded to the benzene ring lie in the ring plane. Intramolecular C—H⋯O hydrogen bonding results in the formation of a five-membered planar ring, which is oriented at a dihedral angle of 2.73 (3)° with respect to the benzene ring, so they are nearly coplanar. In the crystal structure, intermolecular N—H⋯O hydrogen bonds link the molecules into chains elongated along the c axis and stacked along the b axis.

Related literature

For related literature, see: Ries et al. (1993 ); Engeli et al. (2000 ); Kintscher et al. (2004 ); Goossens et al. (2003 ); Kurtz et al. (2004 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₉H₁₁NO₂
M_r = 165.19
Monoclinic, P 2₁ /c
a = 7.5670 (15) Å
b = 6.1080 (12) Å
c = 18.127 (4) Å
β = 98.14 (3)°
V = 829.4 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 294 (2) K
0.40 × 0.30 × 0.20 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.963, T_max = 0.981
1747 measured reflections
1620 independent reflections
1079 reflections with I > 2σ(I)
R_int = 0.022
3 standard reflections every 200 reflections intensity decay: none

Refinement

R[F² > 2σ(F²)] = 0.053
wR(F²) = 0.188
S = 1.04
1620 reflections
109 parameters
H-atom parameters constrained
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4A⋯O1	0.93	2.40	2.728 (4)	100
N—H0B⋯O2ⁱ	0.86	2.37	3.142 (3)	150
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CAD-4 Software (Enraf–Nonius, 1985 ); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); 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: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808006223/hk2431sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808006223/hk2431Isup2.hkl

checkCIF report

Comment top

Methyl 3-methyl-4-aminobenzoate is important as an intermedicine to prepare telmisartan, an angiotensin II receptor blocker, on the development of obesity and related metabolic disorders in diet-induced obese mice (Ries et al., 1993). Telmisartan can be used as a therapeutic tool for metabolic syndrome, including visceral obesity (Engeli et al., 2000; Kintscher et al., 2004; Goossens et al., 2003; Kurtz et al., 2004). As part of our studies in this area, we report herein the synthesis and crystal structure of the title compound, (I).

In the molecule of (I), (Fig. 1), the ligand bond lengths (Allen et al., 1987) and angles are within normal ranges. The atoms N and C9 lie in the benzene ring plane. The intramolecular C—H···O hydrogen bond (Table 1) results in the formation of a five-membered planar ring A (O1/C2/C3/C4/H4A), in which it is oriented with respect to the six-membered planar ring B (C3—C8) at a dihedral angle of A/B = 2.73 (3)°. So, they are also nearly coplanar.

In the crystal structure, intermolecular N—H···O hydrogen bonds (Table 1) link the molecules into chains elongated along the c axis and stacked along the b axis (Fig. 2), in which they may be effective in the stabilization of the structure.

Related literature top

For related literature, see: Ries et al. (1993); Engeli et al. (2000); Kintscher et al. (2004); Goossens et al. (2003); Kurtz et al. (2004). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound (I) was prepared from 3-methyl-4-aminobenzoic acid (38 g, 250 mmol) in methanol (101 ml, 250 mmol). After the solid has melted, concentrated sulfuric acid (16 ml, 300 mmol) was dropped from the dropping funnel at 363 K, the latter was treated with a mixture of ice and water. The product was filtered by suction. Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of an ethanol solution.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1985); cell refinement: CAD-4 Software (Enraf–Nonius, 1985); data reduction: XCAD4 (Harms & Wocadlo, 1995); 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: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. A packing diagram for (I). Hydrogen bonds are shown as dashed lines.

Methyl 4-amino-3-methylbenzoate top

Crystal data top

C₉H₁₁NO₂	F(000) = 352
M_r = 165.19	D_x = 1.323 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 391(2) K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 7.5670 (15) Å	Cell parameters from 25 reflections
b = 6.1080 (12) Å	θ = 9–13°
c = 18.127 (4) Å	µ = 0.09 mm⁻¹
β = 98.14 (3)°	T = 294 K
V = 829.4 (3) Å³	Block, colorless
Z = 4	0.40 × 0.30 × 0.20 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	1079 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.022
Graphite monochromator	θ_max = 26.0°, θ_min = 2.3°
ω/2θ scans	h = −9→9
Absorption correction: ψ scan (North et al., 1968)	k = 0→7
T_min = 0.963, T_max = 0.981	l = 0→22
1747 measured reflections	3 standard reflections every 200 reflections
1620 independent reflections	intensity decay: none

Refinement top

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)] = 0.053	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.188	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.06P)² + 1.3P] where P = (F_o² + 2F_c²)/3
1620 reflections	(Δ/σ)_max < 0.001
109 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₉H₁₁NO₂	V = 829.4 (3) Å³
M_r = 165.19	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.5670 (15) Å	µ = 0.09 mm⁻¹
b = 6.1080 (12) Å	T = 294 K
c = 18.127 (4) Å	0.40 × 0.30 × 0.20 mm
β = 98.14 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	1079 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.022
T_min = 0.963, T_max = 0.981	3 standard reflections every 200 reflections
1747 measured reflections	intensity decay: none
1620 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.053	0 restraints
wR(F²) = 0.188	H-atom parameters constrained
S = 1.04	Δρ_max = 0.25 e Å⁻³
1620 reflections	Δρ_min = −0.27 e Å⁻³
109 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
N	0.8206 (4)	0.4908 (5)	0.17914 (15)	0.0570 (8)
H0A	0.8716	0.6166	0.1792	0.068*
H0B	0.7811	0.4279	0.1376	0.068*
O1	0.6922 (3)	−0.1169 (4)	0.44629 (12)	0.0549 (7)
O2	0.8163 (4)	0.1644 (4)	0.51362 (13)	0.0621 (8)
C1	0.6852 (5)	−0.2393 (6)	0.51341 (18)	0.0561 (10)
H1A	0.6303	−0.3788	0.5012	0.084*
H1B	0.6164	−0.1599	0.5451	0.084*
H1C	0.8041	−0.2610	0.5388	0.084*
C2	0.7641 (4)	0.0832 (5)	0.45389 (18)	0.0440 (8)
C3	0.7726 (4)	0.1877 (5)	0.38130 (17)	0.0404 (7)
C4	0.7052 (4)	0.0892 (5)	0.31364 (17)	0.0423 (8)
H4A	0.6496	−0.0464	0.3145	0.051*
C5	0.7176 (4)	0.1847 (5)	0.24532 (17)	0.0405 (8)
C6	0.8021 (4)	0.3903 (5)	0.24530 (17)	0.0414 (7)
C7	0.8662 (4)	0.4927 (5)	0.31251 (18)	0.0450 (8)
H7A	0.9196	0.6297	0.3120	0.054*
C8	0.8517 (4)	0.3940 (5)	0.37935 (18)	0.0427 (8)
H8A	0.8947	0.4649	0.4237	0.051*
C9	0.6433 (5)	0.0725 (6)	0.17397 (18)	0.0525 (9)
H9A	0.5906	−0.0644	0.1851	0.079*
H9B	0.7377	0.0463	0.1448	0.079*
H9C	0.5541	0.1639	0.1464	0.079*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N	0.076 (2)	0.0464 (17)	0.0479 (17)	−0.0106 (16)	0.0050 (15)	0.0071 (14)
O1	0.0748 (17)	0.0429 (13)	0.0455 (13)	−0.0097 (13)	0.0031 (11)	0.0032 (11)
O2	0.090 (2)	0.0538 (16)	0.0409 (13)	−0.0084 (14)	0.0053 (13)	−0.0040 (12)
C1	0.076 (3)	0.048 (2)	0.0449 (19)	−0.0029 (19)	0.0100 (17)	0.0037 (16)
C2	0.0489 (19)	0.0416 (18)	0.0418 (17)	0.0019 (16)	0.0079 (14)	−0.0005 (15)
C3	0.0425 (17)	0.0373 (17)	0.0414 (17)	0.0040 (14)	0.0058 (13)	−0.0029 (14)
C4	0.0430 (18)	0.0349 (17)	0.0479 (18)	−0.0003 (14)	0.0021 (14)	−0.0008 (14)
C5	0.0419 (18)	0.0344 (16)	0.0435 (17)	0.0038 (14)	0.0003 (13)	−0.0020 (14)
C6	0.0448 (18)	0.0325 (16)	0.0468 (17)	0.0050 (14)	0.0065 (14)	0.0022 (14)
C7	0.0458 (19)	0.0327 (16)	0.056 (2)	−0.0036 (14)	0.0061 (15)	−0.0014 (15)
C8	0.0477 (18)	0.0372 (17)	0.0434 (17)	0.0030 (15)	0.0071 (13)	−0.0067 (14)
C9	0.057 (2)	0.051 (2)	0.0469 (19)	−0.0055 (17)	−0.0031 (16)	−0.0022 (16)

Geometric parameters (Å, º) top

N—C6	1.372 (4)	C4—C5	1.384 (4)
N—H0A	0.8600	C4—H4A	0.9300
N—H0B	0.8600	C5—C6	1.410 (4)
O1—C2	1.336 (4)	C5—C9	1.501 (4)
O1—C1	1.435 (4)	C6—C7	1.394 (4)
C1—H1A	0.9600	C7—C8	1.372 (4)
C1—H1B	0.9600	C7—H7A	0.9300
C1—H1C	0.9600	C8—H8A	0.9300
O2—C2	1.206 (4)	C9—H9A	0.9600
C2—C3	1.472 (4)	C9—H9B	0.9600
C3—C4	1.396 (4)	C9—H9C	0.9600
C3—C8	1.398 (4)

C6—N—H0A	120.0	C4—C5—C6	117.6 (3)
C6—N—H0B	120.0	C4—C5—C9	120.9 (3)
H0A—N—H0B	120.0	C6—C5—C9	121.4 (3)
C2—O1—C1	116.9 (3)	N—C6—C7	119.9 (3)
O1—C1—H1A	109.5	N—C6—C5	120.1 (3)
O1—C1—H1B	109.5	C7—C6—C5	120.1 (3)
H1A—C1—H1B	109.5	C8—C7—C6	120.9 (3)
O1—C1—H1C	109.5	C8—C7—H7A	119.5
H1A—C1—H1C	109.5	C6—C7—H7A	119.5
H1B—C1—H1C	109.5	C7—C8—C3	120.4 (3)
O2—C2—O1	123.1 (3)	C7—C8—H8A	119.8
O2—C2—C3	125.0 (3)	C3—C8—H8A	119.8
O1—C2—C3	111.9 (3)	C5—C9—H9A	109.5
C4—C3—C8	118.1 (3)	C5—C9—H9B	109.5
C4—C3—C2	122.8 (3)	H9A—C9—H9B	109.5
C8—C3—C2	119.1 (3)	C5—C9—H9C	109.5
C5—C4—C3	122.8 (3)	H9A—C9—H9C	109.5
C5—C4—H4A	118.6	H9B—C9—H9C	109.5
C3—C4—H4A	118.6

C1—O1—C2—O2	−2.4 (5)	C4—C5—C6—N	179.0 (3)
C1—O1—C2—C3	177.0 (3)	C9—C5—C6—N	−1.1 (5)
O2—C2—C3—C4	−178.0 (3)	C4—C5—C6—C7	−1.4 (4)
O1—C2—C3—C4	2.7 (4)	C9—C5—C6—C7	178.5 (3)
O2—C2—C3—C8	2.2 (5)	N—C6—C7—C8	−179.0 (3)
O1—C2—C3—C8	−177.2 (3)	C5—C6—C7—C8	1.3 (5)
C8—C3—C4—C5	1.7 (5)	C6—C7—C8—C3	0.3 (5)
C2—C3—C4—C5	−178.2 (3)	C4—C3—C8—C7	−1.7 (5)
C3—C4—C5—C6	−0.1 (5)	C2—C3—C8—C7	178.1 (3)
C3—C4—C5—C9	180.0 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4A···O1	0.93	2.40	2.728 (4)	100
N—H0B···O2ⁱ	0.86	2.37	3.142 (3)	150

Symmetry code: (i) x, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₉H₁₁NO₂
M_r	165.19
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	294
a, b, c (Å)	7.5670 (15), 6.1080 (12), 18.127 (4)
β (°)	98.14 (3)
V (Å³)	829.4 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.40 × 0.30 × 0.20

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.963, 0.981
No. of measured, independent and observed [I > 2σ(I)] reflections	1747, 1620, 1079
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.616

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.053, 0.188, 1.04
No. of reflections	1620
No. of parameters	109
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.27

Computer programs: CAD-4 Software (Enraf–Nonius, 1985), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4A···O1	0.93	2.40	2.728 (4)	100.30
N—H0B···O2ⁱ	0.86	2.37	3.142 (3)	149.88

Symmetry code: (i) x, −y+1/2, z−1/2.

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for support.

References

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