1,4-Dibenzyl­piperazine

Meng Zhang; Yong-hong Zhou; Li-hong Hu; Xiao-hui Yang

doi:10.1107/S1600536810049111

. 2010 Nov 27;66(Pt 12):o3336. doi: 10.1107/S1600536810049111

1,4-Dibenzylpiperazine

Meng Zhang ^a, Yong-hong Zhou ^a,^*, Li-hong Hu ^a, Xiao-hui Yang ^a

PMCID: PMC3011390 PMID: 21589610

Abstract

In the title compound, C₁₈H₂₂N₂, which possesses non-crystallographic inversion symmetry, the central piperazine ring adopts a chair conformation. The phenyl rings are not exactly parallel and make a dihedral angle of 1.3 (1)°. No significant intermolecular contacts are observed in the crystal.

Related literature

For the properties and applications of piperazine derivatives, see: Zhao et al. (2002 ▶); Sonurlikar et al. (1977 ▶); Bigoli et al. (2001 ▶). For the synthesis of related compounds, see: Zheng et al. (2005 ▶); Sarangarajan et al. (2005 ▶). For related structures, see: Yogavel et al. (2003 ▶); Gunasekaran et al. (1996 ▶); Thirumurugan et al. (1998 ▶).

Experimental

Crystal data

C₁₈H₂₂N₂
M _r = 266.38
Orthorhombic,
a = 7.5130 (15) Å
b = 19.127 (4) Å
c = 21.366 (4) Å
V = 3070.3 (11) Å³
Z = 8
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 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 = 0.980, T _max = 0.993
5468 measured reflections
2781 independent reflections
1650 reflections with I > 2σ(I)
R _int = 0.045
3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F ² > 2σ(F ²)] = 0.052
wR(F ²) = 0.141
S = 1.01
2781 reflections
182 parameters
H-atom parameters constrained
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.13 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 EXPRESS; 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

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810049111/bh2322sup1.cif

e-66-o3336-sup1.cif^{(18.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810049111/bh2322Isup2.hkl

e-66-o3336-Isup2.hkl^{(136.6KB, hkl)}

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

Acknowledgments

This work was supported by the 948 program of the State Forestry Administration (2009–4–55).

supplementary crystallographic information

Comment

The structural study of piperazine derivatives is of interest, because some piperazine-containing derivatives constitute a novel class of mixed D2/D4 receptor antagonists (Zhao et al., 2002), and disubstituted piperazine derivatives are antifilarial, antiamoebic and spermicidal agents (Sonurlikar et al., 1977). In addition, piperazine derivatives are useful precursors of mixed-ligand dithiolenes of interest for non-linear optics (Bigoli et al., 2001). Recently, many piperazine derivatives with various substituents have been synthesized (Zheng et al., 2005; Sarangarajan et al., 2005). Herein, we report the crystal structure of the title compound, (I).

The geometry and labeling scheme of the title compound are depicted in Fig. 1, and the packing structure is given in Fig. 2. The piperazine ring exhibits a chair conformation with the usual bond lengths and angles (Yogavel et al., 2003), comparable with those of related reported structures (Gunasekaran et al., 1996; Thirumurugan et al., 1998).

Experimental

To a solution of anhydrous piperazine (5 mmol, 0.43 g) in CH₂Cl₂ (20 ml) was added 2.2 equivalents of triethylamine (1.5 ml), followed by benzyl bromide (10 mmol, 2.66 g) in CH₂Cl₂ (20 ml). After the mixture had been stirred for 10 min., the solvent was removed using a rotary evaporator. The solid residue was washed with water and recrystallized from ethanol-cyclohexane to give a colourless solid (76% yield). Crystals of (I) suitable for X-ray diffraction were obtained by slow evaporation of an ethanol solution.