Methyl 5-bromo-6-methyl­picolinate

Abstract

The title compound, C₈H₈BrNO₂, does not show any significant inter­molecular π–π or C—H⋯π inter­actions in the crystal packing except for one weak Br⋯Br [3.715 (1) Å] inter­action.

Related literature

The title compound is an important inter­mediate for the construction of novel supported PyOX ligands, see: Oila et al. (2005 ▶). For bond-length data, see: Allen et al. (1987 ▶).

Experimental

Crystal data

• C₈H₈BrNO₂

• M _r = 230.06

• Monoclinic,

• a = 18.518 (4) Å

• b = 4.1040 (8) Å

• c = 12.442 (3) Å

• β = 109.52 (3)°

• V = 891.2 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 4.57 mm⁻¹

• T = 293 (2) K

• 0.20 × 0.10 × 0.10 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.462, T _max = 0.658

• 1602 measured reflections

• 1602 independent reflections

• 975 reflections with I > 2σ(I)

• 3 standard reflections every 200 reflections intensity decay: 1%

Refinement

• R[F ² > 2σ(F ²)] = 0.061

• wR(F ²) = 0.066

• S = 1.75

• 1602 reflections

• 110 parameters

• H-atom parameters constrained

• Δρ_max = 0.53 e Å⁻³

• Δρ_min = −0.61 e Å⁻³

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.

Supplementary Material

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

supplementary crystallographic information

Comment

The title compound is one of important intermediates for construction of novel supported PyOX-ligands (Oila et al., 2005). Here we report the crystal structure of the title compound, methyl 5-bromo-6-methylpicolinate (Fig. 1).

In the title compound, the bond lengths and angles are within normal ranges (Allen et al., 1987). The crystal structure is stabilized by a weak Br···Brⁱ interaction at 3.715 (1) Å (Fig. 2; symmetry code as in Fig. 2).

Experimental

The title compound, (I) was prepared by a method reported in literature (Oila et al., 2005) with some modification. The crystals were obtained by dissolving I (0.2 g) in methanol (50 ml) and evaporating the solvent slowly at room temperature for about 3 d.

Refinement

H atoms were positioned geometrically, with O—H = 0.82 and C—H = 0.93 Å for aromatic H, and constrained to ride on their parent atoms, with U_iso(H) = xU_eq(C/O), where x = 1.2 for aromatic H and x = 1.5 for other H.

Figures

Fig. 1.

A drawing of the title molecular structure, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

Fig. 2.

Br···Br interaction in the title compound. [Symmetry code: (i) -x+1, y+1/2, -z+1/2.]

Crystal data

C8H8BrNO2	F(000) = 456
Mr = 230.06	Dx = 1.715 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 18.518 (4) Å	θ = 10–14°
b = 4.1040 (8) Å	µ = 4.57 mm−1
c = 12.442 (3) Å	T = 293 K
β = 109.52 (3)°	Block, colorless
V = 891.2 (4) Å3	0.20 × 0.10 × 0.10 mm
Z = 4

Data collection

Enraf–Nonius CAD-4 diffractometer	975 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.0000
graphite	θmax = 25.3°, θmin = 1.2°
ω/2θ scans	h = −22→20
Absorption correction: ψ scan (North et al., 1968)	k = 0→4
Tmin = 0.462, Tmax = 0.658	l = 0→14
1602 measured reflections	3 standard reflections every 200 reflections
1602 independent reflections	intensity decay: 1%

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)] = 0.061	Hydrogen site location: difference Fourier map
wR(F2) = 0.066	H-atom parameters constrained
S = 1.75	w = 1/[σ2(Fo2)]
1602 reflections	(Δ/σ)max < 0.000
110 parameters	Δρmax = 0.53 e Å−3
0 restraints	Δρmin = −0.61 e Å−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Br	0.41815 (4)	0.6507 (2)	0.25731 (6)	0.0546 (3)
O1	0.0882 (2)	−0.1451 (13)	0.2125 (3)	0.0691 (16)
O2	0.1349 (2)	−0.0435 (11)	0.3986 (4)	0.0533 (15)
N	0.2635 (3)	0.2009 (15)	0.3797 (4)	0.0450 (17)
C1	0.3893 (3)	0.4149 (17)	0.4811 (4)	0.067 (2)
H1A	0.3707	0.3787	0.5434	0.101*
H1B	0.4059	0.6370	0.4822	0.101*
H1C	0.4317	0.2717	0.4882	0.101*
C2	0.3260 (3)	0.3477 (18)	0.3698 (5)	0.0344 (16)
C3	0.3290 (3)	0.4444 (16)	0.2646 (5)	0.039 (2)
C4	0.2680 (3)	0.3789 (19)	0.1651 (5)	0.059 (2)
H4A	0.2702	0.4358	0.0939	0.071*
C5	0.2053 (3)	0.2298 (18)	0.1755 (5)	0.050 (2)
H5A	0.1632	0.1866	0.1109	0.060*
C6	0.2038 (3)	0.1425 (19)	0.2814 (5)	0.0426 (18)
C7	0.1372 (4)	−0.0335 (18)	0.2958 (6)	0.050 (2)
C8	0.0676 (3)	−0.1896 (19)	0.4127 (5)	0.070 (2)
H8A	0.0724	−0.1875	0.4920	0.104*
H8B	0.0627	−0.4104	0.3857	0.104*
H8C	0.0230	−0.0679	0.3698	0.104*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br	0.0482 (4)	0.0590 (5)	0.0589 (5)	−0.0020 (6)	0.0211 (3)	0.0028 (6)
O1	0.048 (3)	0.092 (4)	0.055 (4)	−0.011 (4)	0.001 (3)	−0.013 (4)
O2	0.043 (3)	0.070 (4)	0.046 (3)	−0.007 (3)	0.013 (2)	−0.002 (3)
N	0.029 (3)	0.065 (5)	0.033 (3)	−0.006 (4)	0.000 (3)	0.004 (4)
C1	0.056 (4)	0.087 (7)	0.043 (4)	−0.027 (5)	−0.004 (4)	0.012 (5)
C2	0.026 (4)	0.031 (4)	0.035 (4)	−0.003 (4)	−0.004 (3)	−0.004 (5)
C3	0.034 (4)	0.045 (6)	0.040 (4)	0.002 (4)	0.014 (4)	0.009 (4)
C4	0.049 (4)	0.088 (7)	0.033 (4)	0.004 (6)	0.005 (4)	0.031 (5)
C5	0.038 (4)	0.076 (7)	0.029 (4)	0.001 (4)	0.002 (3)	0.002 (4)
C6	0.025 (4)	0.060 (5)	0.042 (4)	0.004 (5)	0.011 (3)	−0.001 (5)
C7	0.037 (5)	0.060 (6)	0.043 (5)	0.004 (4)	0.000 (4)	−0.010 (5)
C8	0.051 (4)	0.079 (7)	0.089 (5)	−0.011 (5)	0.037 (4)	0.010 (6)

Geometric parameters (Å, °)

Br—Bri	3.715 (1)	C2—C3	1.387 (6)
Br—C3	1.884 (5)	C3—C4	1.396 (6)
O1—C7	1.218 (6)	C4—C5	1.356 (7)
O2—C7	1.294 (6)	C4—H4A	0.9300
O2—C8	1.446 (6)	C5—C6	1.375 (7)
N—C2	1.347 (6)	C5—H5A	0.9300
N—C6	1.368 (6)	C6—C7	1.491 (8)
C1—C2	1.510 (6)	C8—H8A	0.9600
C1—H1A	0.9600	C8—H8B	0.9600
C1—H1B	0.9600	C8—H8C	0.9600
C1—H1C	0.9600
C7—O2—C8	116.6 (5)	C3—C4—H4A	121.0
C2—N—C6	117.3 (5)	C4—C5—C6	120.0 (6)
C2—C1—H1A	109.5	C4—C5—H5A	120.0
C2—C1—H1B	109.5	C6—C5—H5A	120.0
H1A—C1—H1B	109.5	N—C6—C5	122.9 (6)
C2—C1—H1C	109.5	N—C6—C7	115.5 (6)
H1A—C1—H1C	109.5	C5—C6—C7	121.6 (6)
H1B—C1—H1C	109.5	O1—C7—O2	124.6 (7)
N—C2—C3	121.4 (5)	O1—C7—C6	119.4 (7)
N—C2—C1	115.2 (5)	O2—C7—C6	115.9 (6)
C3—C2—C1	123.3 (6)	O2—C8—H8A	109.5
C4—C3—C2	120.4 (5)	O2—C8—H8B	109.5
C4—C3—Br	120.5 (5)	H8A—C8—H8B	109.5
C2—C3—Br	119.1 (5)	O2—C8—H8C	109.5
C5—C4—C3	117.9 (6)	H8A—C8—H8C	109.5
C5—C4—H4A	121.0	H8B—C8—H8C	109.5
C6—N—C2—C3	1.8 (10)	C2—N—C6—C7	177.4 (6)
C6—N—C2—C1	178.4 (6)	C4—C5—C6—N	0.4 (11)
N—C2—C3—C4	−2.7 (11)	C4—C5—C6—C7	−177.5 (7)
C1—C2—C3—C4	−179.0 (6)	C8—O2—C7—O1	−2.1 (11)
N—C2—C3—Br	179.6 (5)	C8—O2—C7—C6	175.0 (6)
C1—C2—C3—Br	3.3 (9)	N—C6—C7—O1	−167.1 (7)
C2—C3—C4—C5	2.3 (11)	C5—C6—C7—O1	11.0 (11)
Br—C3—C4—C5	180.0 (5)	N—C6—C7—O2	15.6 (9)
C3—C4—C5—C6	−1.2 (11)	C5—C6—C7—O2	−166.3 (7)
C2—N—C6—C5	−0.6 (10)

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