3-[(1-Benzyl-1H-1,2,3-triazol-5-yl)meth­yl]-6-bromo-2-phenyl-3H-imidazo[4,5-b]pyridine

Younes Ouzidan; Youssef Kandri Rodi; Frank R Fronczek; Ramaiyer Venkatraman; El Mokhtar Essassi; Lahcen El Ammari

doi:10.1107/S1600536811009123

. 2011 Mar 15;67(Pt 4):o890–o891. doi: 10.1107/S1600536811009123

3-[(1-Benzyl-1H-1,2,3-triazol-5-yl)methyl]-6-bromo-2-phenyl-3H-imidazo[4,5-b]pyridine

Younes Ouzidan ^a, Youssef Kandri Rodi ^a,^*, Frank R Fronczek ^b, Ramaiyer Venkatraman ^c, El Mokhtar Essassi ^d, Lahcen El Ammari ^e

PMCID: PMC3099998 PMID: 21754166

Abstract

There are two crystallographically independent molecules in the asymmetric unit of the title compound, C₂₂H₁₇BrN₆. The dihedral angles between the imidazo[4,5-b]pyridine mean plane and the phenyl rings are 20.4 (2) and 24.0 (2)° in the two molecules. The orientation of triazoles compared to the imidazo[4,5-b]pyridine system is almost the same in both molecules, with dihedral angles of 64.2 (2) and 65.1 (2)°. However, the main difference between the two molecules lies in the arrangement of the phenyl groups compared to imidazo[4,5-b]pyridine in each molecule. Indeed, in the first molecule the dihedral angle between the plane of the phenyl ring and that of the imidazo[4,5-b]pyridine system is 67.7 (2)°, while in the second molecule the plane of the phenyl ring is almost perpendicular to that of the imidazo[4,5-b]pyridine system with a dihedral angle of 86.0 (2)°.

Related literature

For background literature on the medicinal properties of imidazo[4,5-b]pyridine and its derivatives, see: Jiyeon et al. (2010 ▶); Passannanti et al. (1998 ▶); Bavetsias et al. (2007 ▶); Tomczuk et al. (1991 ▶); Ouzidan, Obbade et al. (2010 ▶); Ouzidan, Rodi et al. (2010 ▶).

Experimental

Crystal data

C₂₂H₁₇BrN₆
M _r = 445.33
Monoclinic,
a = 41.122 (6) Å
b = 5.8358 (10) Å
c = 15.988 (3) Å
β = 93.922 (6)°
V = 3827.8 (11) Å³
Z = 8
Mo Kα radiation
μ = 2.17 mm⁻¹
T = 93 K
0.32 × 0.05 × 0.01 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997 ▶) T _min = 0.878, T _max = 0.979
14153 measured reflections
7510 independent reflections
4016 reflections with I > 2σ(I)
R _int = 0.088

Refinement

R[F ² > 2σ(F ²)] = 0.048
wR(F ²) = 0.109
S = 0.96
7510 reflections
524 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Data collection: COLLECT (Nonius, 2000 ▶); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ▶); data reduction: DENZO (Otwinowski & Minor, 1997 ▶) and SCALEPACK; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ▶), ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2009 ▶)’; software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811009123/dn2663sup1.cif

e-67-0o890-sup1.cif^{(31.9KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811009123/dn2663Isup2.hkl

e-67-0o890-Isup2.hkl^{(360KB, hkl)}

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

supplementary crystallographic information

Comment

This work is a result of an extensive program of scientific research on the synthesis and characterization of imidazo[4,5-b]pyridine and its derivatives started in the laboratory since two years (Ouzidan, Obbade et al. 2010; Ouzidan, Rodi et al. 2010). It is motivated by numerous applications of these compounds in medicinal chemistry (Passannanti et al., (1998); Tomczuk et al., (1991)). Furthermore, the imidazo[4,5-b]pyridine moiety is also an important heterocyclic nucleus which has been used extensively in medicinal chemistry. In fact, the heterocycles derived from these intermediates have been tested for their potential as anti-neuroinflammatory (Jiyeon et al., (2010); Bavetsias et al., (2007).

In this work we have synthesized 3-((3-benzyl-3H-1,2,3-triazol-4-yl)methyl)- 6-bromo-2-phenyl-3H-imidazo[4,5-b]pyridine by 1,3-dipolar cycloaddition reaction of benzyl azide with 6-bromo-2-phenyl-3-(prop-2-ynyl)-3H-imidazo [4,5-b]pyridine.

The plot of the two molecules building the asymmetric unit of the crystal structure of 3-((3-benzyl-3H-1,2,3-triazol-4-yl)methyl)-6-bromo-2- phenyl-3H-ιmidazo[4,5-b]pyridine is shown in Fig. 1. The two cycles forming the imidazo[4,5-b]pyridine are almost planar and form dihedral angles with the phenyl rings of 20.4 (2)° and 24.0 (2)°, in the first and in the second molecule respectively. Moreover, the dihedral angle between the phenyl ring and the imidazo[4,5-b]pyridine system is 67.7 (2) °, in the first while in the second molecule the phenyl is almost perpendicular to the imidazo[4,5-b]pyridine system with a dihedral angle of 86.0 (2) ° as shown in Fig.2 which represents the fitting of the two molecules.

Experimental

To a solution of 6-bromo-2-phenyl-3-(prop-2-ynyl)-3H-imidazo[4,5-b]pyridine (0.2 g, 0.64 mmol) in ethanol (15 ml) was added benzyl azide (0.1 ml, 0.77 mmol). The mixture was stirred under reflux for 72 h. After completion of reaction (monitored by TLC), the solution was concentrated and the residue was purified by column chromatography on silica gel by using a mixture (hexane/ethyl acetate 2/1). Crystals were obtained when the solvent was allowed to evaporate.