tert-Butyl N-(5-bromo-1H-imidazo[4,5-b]pyridin-2-ylmeth­yl)carbamate

Ling Yin; Jiong Jia; Gui-Long Zhao; Jian-Wu Wang

doi:10.1107/S1600536808035393

. 2008 Nov 8;64(Pt 12):o2262. doi: 10.1107/S1600536808035393

tert-Butyl N-(5-bromo-1H-imidazo[4,5-b]pyridin-2-ylmethyl)carbamate

Ling Yin ^a, Jiong Jia ^a,^*, Gui-Long Zhao ^b, Jian-Wu Wang ^a

PMCID: PMC2959901 PMID: 21581243

Abstract

In the molecule of the title compound, C₁₂H₁₅BrN₄O₂, the imidazole and pyridine rings are strictly coplanar [maximum deviation 0.006 (3) Å]. In the crystal structure, molecules are linked into chains running parallel to the a axis by intermolecular N—H⋯O hydrogen bonds. Centrosymmetrically related chains are further connected by N—H⋯N hydrogen-bonding interactions to form a two-dimensional layer structure parallel to the ab plane.

Related literature

For general background on the properties of imidazole derivatives, see: Dai et al. (2004 ▶); Durant et al. (1973 ▶); Wang et al. (2007 ▶). For the crystal structures of related compounds, see: Lorenc et al. (2008 ▶).

Experimental

Crystal data

C₁₂H₁₅BrN₄O₂
M _r = 327.19
Orthorhombic,
a = 10.7400 (11) Å
b = 9.6717 (9) Å
c = 28.215 (3) Å
V = 2930.8 (5) Å³
Z = 8
Mo Kα radiation
μ = 2.81 mm⁻¹
T = 298 (2) K
0.20 × 0.10 × 0.05 mm

Data collection

Bruker SMART APEX area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2002 ▶) T _min = 0.604, T _max = 0.872
16102 measured reflections
3374 independent reflections
2285 reflections with I > 2σ(I)
R _int = 0.031

Refinement

R[F ² > 2σ(F ²)] = 0.038
wR(F ²) = 0.102
S = 1.01
3374 reflections
180 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.72 e Å⁻³
Δρ_min = −0.65 e Å⁻³

Data collection: SMART (Bruker, 2002 ▶); cell refinement: SAINT (Bruker, 2002 ▶); data reduction: SAINT; 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: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808035393/rz2259sup1.cif

e-64-o2262-sup1.cif^{(17.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808035393/rz2259Isup2.hkl

e-64-o2262-Isup2.hkl^{(165.6KB, hkl)}

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—H2⋯N1ⁱ	0.81 (3)	2.12 (3)	2.911 (3)	165 (3)
N4—H3A⋯O1ⁱⁱ	0.84 (3)	1.98 (3)	2.822 (3)	178 (2)

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

The authors thank the National Basic Research Priority Program for the Science Fund grant No. 2003CCA027.

supplementary crystallographic information

Comment

Nitrogen heterocyclic compounds and their derivatives are substances which show diverse biological activity (Dai et al., 2004). Among them, imidazo[4,5-b]pyridine compounds are an important class of imidazole derivatives, which are widely used in the field of medicine (Durant et al., 1973; Wang et al., 2007). As a continuation of our studies on this subject, the structure of the title compound is described herein.

In the molecule of the title compound (Fig. 1) the imidazole and pyridine rings are strictly coplanar, the maximum deviation from the mean plane of the two rings being 0.006 (3) Å for atom C4. The C6—N2 and C6—N3 bond lengths in the imidazole ring are 1.362 (3) and 1.310 (3) Å, respectively; the bond angles between non-hydrogen atoms of the pyridine ring are in the range 114.3 (2)–126.8 (2)°, which is in line with the values reported for similar compounds (Lorenc et al., 2008). In the crystal packing, intermolecular N—H···O hydrogen bonds involving the amide and carbonyl groups (Table 1) link adjacent molecules into chains parallel to the a axis. Centrosymmetrically related chains are further linked by intermolecular N—H···N hydrogen bonds to form a two-dimensional layer structure parallel to the ab plane (Fig. 2).

Experimental

5-Bromopyridine-2,3-diamine(3.7 g, 20 mmol) and N-(tert-butoxycarbonyl)glycine (3.5 g, 20 mmol) were dissolved in THF (40 ml) and cooled to 273 K. N,N'-Dicyclohexylcarbodiimide (4.94 g, 24 mmol) was then added in batches and the mixture was stirred at 273 K for half an hour and at room temperature overnight. The filtrate was evaporated to afford a green solid, which was dissolved in acetic acid (20 ml) and the solution was stirred at 353 K for 8 h. The acetic acid was removed under reduced pressure and the crude title compound was separated as a pale green solid. Crystals of the title compound suitable for X-ray analysis were obtained by slow evaporation at room temperature if a dichloromethane-methanol (6:1, v/v) solution (yield; 70%, m.p. 475–476 K).