2-Amino-N,3-dimethyl­benzamide

Abstract

In the title compound, C₉H₁₂N₂O, the mean plane through the amide group and the benzene ring form a dihedral angle of 33.93 (7)°. An intra­molecular N—H⋯O hydrogen bond is present. In the crystal, mol­ecules are linked by N—H⋯N and N—H⋯O hydrogen bonds, forming double-stranded chains parallel to the b axis.

Related literature  

For background to substituted anthranilamides, see: Gnamm et al. (2012 ▶); Lahm et al. (2005 ▶); Norman et al. (1996 ▶); Roe et al. (1999 ▶). For the synthesis, see: Staiger & Wagner (1953 ▶); Coppola (1980 ▶); Witt & Bergman (2000 ▶).

Experimental  

Crystal data  

• C₉H₁₂N₂O

• M _r = 164.21

• Monoclinic,

• a = 9.833 (6) Å

• b = 5.011 (3) Å

• c = 9.841 (6) Å

• β = 118.27 (1)°

• V = 427.1 (4) ų

• Z = 2

• Mo Kα radiation

• μ = 0.09 mm⁻¹

• T = 173 K

• 0.36 × 0.13 × 0.10 mm

Data collection  

• Rigaku MM007-HF CCD (Saturn 724+) diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku, 2007 ▶) T _min = 0.970, T _max = 0.992

• 3828 measured reflections

• 1939 independent reflections

• 1884 reflections with I > 2σ(I)

• R _int = 0.036

Refinement  

• R[F ² > 2σ(F ²)] = 0.042

• wR(F ²) = 0.111

• S = 1.05

• 1939 reflections

• 112 parameters

• 1 restraint

• H-atom parameters constrained

• Δρ_max = 0.30 e Å⁻³

• Δρ_min = −0.22 e Å⁻³

Data collection: CrystalClear (Rigaku, 2007 ▶); 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: OLEX2 (Dolomanov et al., 2009 ▶); software used to prepare material for publication: SHELXL97.

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—H1A⋯O1	0.88	2.21	2.785 (2)	123
N1—H1B⋯N1i	0.88	2.44	3.240 (2)	151
N2—H2⋯O1ii	0.88	2.18	2.858 (2)	133

Symmetry codes: (i) ; (ii) .

supplementary crystallographic information

Comment

Anthranilamide-based derivatives exhibit interesting biological activities such as antibacterial, antifungal, antiviral and insecticidal effects (Gnamm et al., 2012; Lahm et al., 2005; Norman et al., 1996; Roe et al., 1999). We report here the crystal structure of the title compound 2-amino-N,3-dimethylbenzamide, an important organic intermediate in the synthesis of medicines, agricultural chemicals, and animal drugs.

In the title compound (Fig. 1), the least-square mean plane through the amide group (C8/C9/O1/N2) form a dihedral angle of 33.93 (7)° with the benzene ring. The molecular conformation is stabilized by an intramolecular N—H···O hydrogen bond (Table 1). In the crystal structure, intermolecular N—H···N and N—H···O hydrogen interactions link molecules into double chains running parallel to the b axis.

Experimental

The title compound was prepared according to the literature method (Witt & Bergman, 2000) by stirring isatoic anhydride with aqueous methylamine. Isatoic anhydride was prepared by reaction of anthranilic acid with triphosgene in good yield (Coppola, 1980). The title compound (0.2 g) was dissolved in ethanol (50 ml) at room temperature. Colourless blocks were obtained through slow evaporation after two weeks.

Refinement

The H atoms were placed at calculated positions, with C—H = 0.93–0.98 Å, and refined as riding with U_iso(H) = 1.2–1.5U_eq(C). 841 Friedel pairs were not merged.

Figures

Fig. 1.

The molecular structure of the title compound showing 50% probability displacement ellipsoids and atom-numbering scheme.

Crystal data

C9H12N2O	F(000) = 176
Mr = 164.21	Dx = 1.277 Mg m−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 2240 reflections
a = 9.833 (6) Å	θ = 2.4–32.7°
b = 5.011 (3) Å	µ = 0.09 mm−1
c = 9.841 (6) Å	T = 173 K
β = 118.27 (1)°	Rod, colourless
V = 427.1 (4) Å3	0.36 × 0.13 × 0.10 mm
Z = 2

Data collection

Rigaku MM007-HF CCD (Saturn 724+) diffractometer	1939 independent reflections
Radiation source: rotating anode	1884 reflections with I > 2σ(I)
Confocal monochromator	Rint = 0.036
ω scans at fixed χ = 45°	θmax = 27.5°, θmin = 2.4°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2007)	h = −12→12
Tmin = 0.970, Tmax = 0.992	k = −6→6
3828 measured reflections	l = −12→12

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0574P)2 + 0.1149P] where P = (Fo2 + 2Fc2)/3
1939 reflections	(Δ/σ)max < 0.001
112 parameters	Δρmax = 0.30 e Å−3
1 restraint	Δρmin = −0.22 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
O1	0.18145 (16)	0.6816 (2)	0.25039 (14)	0.0310 (3)
N1	0.08945 (16)	0.5876 (3)	0.47375 (16)	0.0267 (3)
H1A	0.0480	0.5886	0.3725	0.032*
H1B	0.0504	0.4853	0.5193	0.032*
N2	0.22924 (17)	1.1192 (3)	0.24907 (16)	0.0276 (3)
H2	0.2598	1.2682	0.3025	0.033*
C1	0.21634 (17)	0.7472 (3)	0.56154 (18)	0.0215 (3)
C2	0.27443 (18)	0.7589 (3)	0.72312 (19)	0.0245 (3)
C3	0.3954 (2)	0.9304 (4)	0.80932 (19)	0.0300 (4)
H3	0.4353	0.9365	0.9181	0.036*
C4	0.4600 (2)	1.0941 (4)	0.7407 (2)	0.0325 (4)
H4	0.5431	1.2102	0.8019	0.039*
C5	0.40169 (18)	1.0856 (4)	0.58261 (19)	0.0266 (3)
H5	0.4443	1.1990	0.5351	0.032*
C6	0.28106 (17)	0.9128 (3)	0.49133 (17)	0.0211 (3)
C7	0.2030 (2)	0.5880 (4)	0.7989 (2)	0.0330 (4)
H7B	0.0947	0.6394	0.7603	0.050*
H7C	0.2593	0.6139	0.9109	0.050*
H7A	0.2085	0.3999	0.7748	0.050*
C8	0.22609 (17)	0.8953 (3)	0.32129 (18)	0.0214 (3)
C9	0.1841 (2)	1.1254 (4)	0.08586 (19)	0.0343 (4)
H9A	0.0791	1.0551	0.0268	0.051*
H9B	0.2555	1.0156	0.0663	0.051*
H9C	0.1873	1.3098	0.0542	0.051*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0437 (7)	0.0195 (6)	0.0277 (6)	−0.0021 (5)	0.0152 (5)	−0.0023 (4)
N1	0.0268 (7)	0.0240 (6)	0.0291 (7)	−0.0067 (6)	0.0130 (5)	−0.0007 (6)
N2	0.0377 (8)	0.0188 (7)	0.0282 (7)	−0.0033 (6)	0.0173 (6)	−0.0010 (6)
C1	0.0194 (7)	0.0172 (7)	0.0290 (8)	0.0029 (6)	0.0124 (6)	0.0013 (6)
C2	0.0247 (8)	0.0230 (8)	0.0278 (8)	0.0043 (7)	0.0140 (7)	0.0030 (6)
C3	0.0287 (8)	0.0356 (9)	0.0235 (7)	−0.0004 (7)	0.0106 (7)	−0.0026 (7)
C4	0.0271 (8)	0.0344 (9)	0.0328 (8)	−0.0085 (8)	0.0115 (7)	−0.0077 (8)
C5	0.0260 (7)	0.0256 (7)	0.0314 (8)	−0.0056 (7)	0.0162 (7)	−0.0032 (7)
C6	0.0208 (7)	0.0185 (7)	0.0255 (7)	0.0018 (6)	0.0123 (6)	−0.0004 (6)
C7	0.0387 (9)	0.0323 (9)	0.0313 (8)	−0.0008 (8)	0.0192 (7)	0.0052 (8)
C8	0.0207 (7)	0.0181 (7)	0.0272 (7)	0.0016 (6)	0.0127 (6)	0.0007 (6)
C9	0.0431 (10)	0.0314 (10)	0.0286 (8)	−0.0010 (8)	0.0171 (8)	0.0043 (7)

Geometric parameters (Å, º)

O1—C8	1.239 (2)	C3—H3	0.9500
N1—C1	1.386 (2)	C4—C5	1.381 (2)
N1—H1A	0.8800	C4—H4	0.9500
N1—H1B	0.8800	C5—C6	1.398 (2)
N2—C8	1.337 (2)	C5—H5	0.9500
N2—C9	1.450 (2)	C6—C8	1.498 (2)
N2—H2	0.8800	C7—H7B	0.9800
C1—C6	1.410 (2)	C7—H7C	0.9800
C1—C2	1.413 (2)	C7—H7A	0.9800
C2—C3	1.384 (2)	C9—H9A	0.9800
C2—C7	1.510 (2)	C9—H9B	0.9800
C3—C4	1.392 (3)	C9—H9C	0.9800
C1—N1—H1A	120.0	C6—C5—H5	119.5
C1—N1—H1B	120.0	C5—C6—C1	119.49 (14)
H1A—N1—H1B	120.0	C5—C6—C8	120.10 (14)
C8—N2—C9	122.35 (15)	C1—C6—C8	120.36 (14)
C8—N2—H2	118.8	C2—C7—H7B	109.5
C9—N2—H2	118.8	C2—C7—H7C	109.5
N1—C1—C6	121.07 (15)	H7B—C7—H7C	109.5
N1—C1—C2	119.33 (14)	C2—C7—H7A	109.5
C6—C1—C2	119.43 (14)	H7B—C7—H7A	109.5
C3—C2—C1	119.16 (14)	H7C—C7—H7A	109.5
C3—C2—C7	121.00 (16)	O1—C8—N2	121.14 (14)
C1—C2—C7	119.84 (15)	O1—C8—C6	121.59 (14)
C2—C3—C4	121.71 (15)	N2—C8—C6	117.26 (14)
C2—C3—H3	119.1	N2—C9—H9A	109.5
C4—C3—H3	119.1	N2—C9—H9B	109.5
C5—C4—C3	119.12 (16)	H9A—C9—H9B	109.5
C5—C4—H4	120.4	N2—C9—H9C	109.5
C3—C4—H4	120.4	H9A—C9—H9C	109.5
C4—C5—C6	121.09 (15)	H9B—C9—H9C	109.5
C4—C5—H5	119.5
N1—C1—C2—C3	−176.23 (16)	N1—C1—C6—C5	175.30 (15)
C6—C1—C2—C3	−0.9 (2)	C2—C1—C6—C5	0.1 (2)
N1—C1—C2—C7	3.0 (2)	N1—C1—C6—C8	−7.4 (2)
C6—C1—C2—C7	178.30 (16)	C2—C1—C6—C8	177.33 (13)
C1—C2—C3—C4	0.8 (3)	C9—N2—C8—O1	−1.2 (3)
C7—C2—C3—C4	−178.38 (18)	C9—N2—C8—C6	177.79 (15)
C2—C3—C4—C5	0.1 (3)	C5—C6—C8—O1	144.60 (17)
C3—C4—C5—C6	−1.0 (3)	C1—C6—C8—O1	−32.7 (2)
C4—C5—C6—C1	0.9 (3)	C5—C6—C8—N2	−34.4 (2)
C4—C5—C6—C8	−176.35 (16)	C1—C6—C8—N2	148.33 (15)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1	0.88	2.21	2.785 (2)	123
N1—H1B···N1i	0.88	2.44	3.240 (2)	151
N2—H2···O1ii	0.88	2.18	2.858 (2)	133

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