6-Methyl­pyridin-3-amine

Abstract

In the mol­ecule of the title compound, C₆H₈N₂, the methyl C and amine N atoms are 0.021 (2) and 0.058 (2) Å from the pyridine ring plane. In the crystal structure, inter­molecular N—H⋯N hydrogen bonds link the mol­ecules.

Related literature

For a related structure, see: Sawanishi et al. (1987 ▶). For bond-length data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

• C₆H₈N₂

• M _r = 108.14

• Monoclinic,

• a = 8.4240 (17) Å

• b = 7.0560 (14) Å

• c = 10.658 (2) Å

• β = 105.23 (3)°

• V = 611.3 (2) ų

• Z = 4

• Mo Kα radiation

• μ = 0.07 mm⁻¹

• T = 294 (2) K

• 0.30 × 0.20 × 0.10 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.978, T _max = 0.993

• 1183 measured reflections

• 1106 independent reflections

• 746 reflections with I > 2σ(I)

• R _int = 0.059

• 3 standard reflections frequency: 120 min intensity decay: 1%

Refinement

• R[F ² > 2σ(F ²)] = 0.057

• wR(F ²) = 0.154

• S = 1.02

• 1106 reflections

• 73 parameters

• H-atom parameters constrained

• Δρ_max = 0.19 e Å⁻³

• Δρ_min = −0.19 e Å⁻³

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ▶); 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: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 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
N2—H2B⋯N1i	0.86	2.29	3.131 (3)	165

Symmetry code: (i) .

supplementary crystallographic information

Comment

Some derivatives of 3-pyridinecarboxylic acid are important chemical materials. We report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig. 1) the bond lengths (Allen et al., 1987) and angles are within normal ranges. Atoms C1 and N2 are 0.021 (2) Å and 0.058 (2) Å away from the pyridine ring plane.

In the crystal structure, intermolecular N-H···N hydrogen bonds (Table 1) link the molecules, in which they may be effective in the stabilization of the structure.

Experimental

For the preparation of the title compound, bromine (17.3 g) was added slowly to sodium hydroxide solution (303 ml, 5%), and then 3-pyridinecarboxamide (13 g) was added in about 20 min at 273-278 K. The mixture was heated in an oil bath at 343-353 K for 4 h. The product was extracted with CH₂Cl₂, washed with water and dried (yield; 8 g, 77.6%) (Sawanishi et al., 1987). Crystals suitable for X-ray analysis were obtained by slow evaporation of a methanol solution.

Refinement

H atoms were positioned geometrically, with N-H = 0.86 Å (for NH₂) and C-H = 0.93 and 0.96 Å for aromatic and methyl H, respectively, and constrained to ride on their parent atoms with U_iso(H) = xU_eq(C,N), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms.

Figures

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 partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

Crystal data

C6H8N2	F(000) = 232
Mr = 108.14	Dx = 1.175 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 25 reflections
a = 8.4240 (17) Å	θ = 10–12°
b = 7.0560 (14) Å	µ = 0.07 mm−1
c = 10.658 (2) Å	T = 294 K
β = 105.23 (3)°	Block, colorless
V = 611.3 (2) Å3	0.30 × 0.20 × 0.10 mm
Z = 4

Data collection

Enraf–Nonius CAD-4 diffractometer	746 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.059
graphite	θmax = 25.3°, θmin = 2.8°
ω/2θ scans	h = 0→9
Absorption correction: ψ scan (North et al., 1968)	k = 0→8
Tmin = 0.978, Tmax = 0.993	l = −12→12
1183 measured reflections	3 standard reflections every 120 min
1106 independent reflections	intensity decay: 1%

Refinement

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)] = 0.057	H-atom parameters constrained
wR(F2) = 0.154	w = 1/[σ2(Fo2) + (0.05P)2 + 0.5P] where P = (Fo2 + 2Fc2)/3
S = 1.02	(Δ/σ)max < 0.001
1106 reflections	Δρmax = 0.19 e Å−3
73 parameters	Δρmin = −0.19 e Å−3
Primary atom site location: structure-invariant direct methods

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
N1	0.8161 (3)	0.0759 (3)	0.11504 (18)	0.0480 (6)
N2	1.0351 (3)	0.4188 (3)	0.3558 (2)	0.0595 (7)
H2A	0.9692	0.5137	0.3361	0.071*
H2B	1.1237	0.4285	0.4177	0.071*
C1	0.8752 (4)	−0.2454 (4)	0.0569 (3)	0.0616 (8)
H1B	0.7734	−0.2235	−0.0076	0.092*
H1C	0.8626	−0.3507	0.1105	0.092*
H1D	0.9602	−0.2730	0.0148	0.092*
C2	0.9206 (4)	−0.0734 (4)	0.1390 (2)	0.0483 (7)
C3	0.8578 (3)	0.2310 (4)	0.1886 (2)	0.0474 (7)
H3A	0.7857	0.3333	0.1709	0.057*
C4	0.9987 (3)	0.2519 (4)	0.2884 (2)	0.0478 (7)
C5	1.1033 (3)	0.0962 (4)	0.3130 (2)	0.0503 (7)
H5A	1.2009	0.1007	0.3788	0.060*
C6	1.0608 (4)	−0.0656 (4)	0.2385 (2)	0.0544 (7)
H6A	1.1290	−0.1713	0.2566	0.065*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
N1	0.0679 (13)	0.0494 (13)	0.0253 (10)	−0.0054 (11)	0.0098 (9)	0.0006 (10)
N2	0.0703 (15)	0.0579 (15)	0.0413 (13)	0.0013 (12)	−0.0013 (11)	−0.0182 (11)
C1	0.096 (2)	0.0527 (17)	0.0366 (14)	−0.0081 (15)	0.0191 (14)	−0.0067 (13)
C2	0.0835 (18)	0.0426 (14)	0.0242 (12)	−0.0001 (13)	0.0234 (12)	0.0044 (11)
C3	0.0707 (16)	0.0446 (14)	0.0302 (13)	0.0036 (12)	0.0190 (12)	0.0017 (11)
C4	0.0772 (17)	0.0489 (15)	0.0206 (11)	−0.0019 (13)	0.0187 (11)	−0.0033 (11)
C5	0.0622 (15)	0.0554 (16)	0.0301 (12)	0.0096 (13)	0.0062 (11)	0.0047 (12)
C6	0.0844 (19)	0.0481 (15)	0.0326 (13)	0.0087 (14)	0.0190 (13)	0.0038 (12)

Geometric parameters (Å, °)

N1—C3	1.338 (3)	C1—H1D	0.9600
N1—C2	1.353 (3)	C2—C6	1.365 (4)
N2—C4	1.371 (3)	C3—C4	1.378 (4)
N2—H2A	0.8600	C3—H3A	0.9300
N2—H2B	0.8600	C4—C5	1.390 (4)
C1—C2	1.487 (3)	C5—C6	1.383 (4)
C1—H1B	0.9600	C5—H5A	0.9300
C1—H1C	0.9600	C6—H6A	0.9300
C3—N1—C2	117.9 (2)	N1—C3—C4	125.4 (2)
C4—N2—H2A	120.0	N1—C3—H3A	117.3
C4—N2—H2B	120.0	C4—C3—H3A	117.3
H2A—N2—H2B	120.0	N2—C4—C3	121.6 (2)
C2—C1—H1B	109.5	N2—C4—C5	122.5 (2)
C2—C1—H1C	109.5	C3—C4—C5	115.9 (2)
H1B—C1—H1C	109.5	C6—C5—C4	119.2 (2)
C2—C1—H1D	109.5	C6—C5—H5A	120.4
H1B—C1—H1D	109.5	C4—C5—H5A	120.4
H1C—C1—H1D	109.5	C2—C6—C5	121.3 (3)
N1—C2—C6	120.2 (2)	C2—C6—H6A	119.3
N1—C2—C1	118.1 (2)	C5—C6—H6A	119.3
C6—C2—C1	121.7 (3)
C3—N1—C2—C6	2.2 (3)	N2—C4—C5—C6	−178.1 (2)
C3—N1—C2—C1	−179.6 (2)	C3—C4—C5—C6	−0.3 (4)
C2—N1—C3—C4	−0.5 (4)	N1—C2—C6—C5	−2.9 (4)
N1—C3—C4—N2	177.4 (2)	C1—C2—C6—C5	178.9 (2)
N1—C3—C4—C5	−0.4 (4)	C4—C5—C6—C2	1.9 (4)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2B···N1i	0.86	2.29	3.131 (3)	165

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