2,2′-(Piperazine-1,4-di­yl)diacetonitrile

Abstract

The complete mol­ecule of the title compound, C₈H₁₂N₄, is generated by a crystallographic inversion centre. The piperazine ring adopts a chair conformation with the N-bonded substituents in equatorial positions. In the crystal, mol­ecules are linked by C—H⋯N_c (c = cyanide) hydrogen bonds.

Related literature  

For related structures, see: Ma et al. (2007 ▶); Liu & Liu (2011 ▶); Luo & Weng (2011 ▶).

Experimental  

Crystal data  

• C₈H₁₂N₄

• M _r = 164.22

• Monoclinic,

• a = 6.3452 (13) Å

• b = 6.6731 (13) Å

• c = 11.077 (2) Å

• β = 95.61 (3)°

• V = 466.78 (16) ų

• Z = 2

• Mo Kα radiation

• μ = 0.08 mm⁻¹

• T = 293 K

• 0.20 × 0.18 × 0.10 mm

Data collection  

• Rigaku Saturn CCD diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ▶) T _min = 0.985, T _max = 0.992

• 3739 measured reflections

• 1076 independent reflections

• 835 reflections with I > 2σ(I)

• R _int = 0.032

Refinement  

• R[F ² > 2σ(F ²)] = 0.046

• wR(F ²) = 0.150

• S = 1.05

• 1076 reflections

• 55 parameters

• H-atom parameters constrained

• Δρ_max = 0.10 e Å⁻³

• Δρ_min = −0.15 e Å⁻³

Data collection: CrystalClear (Rigaku/MSC, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXL97.

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536812021733/hb6795Isup3.cml

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
C3—H3A⋯N2i	0.97	2.57	3.427 (2)	147

Symmetry code: (i) .

supplementary crystallographic information

Experimental

Piperazine (25 mmol) and triethylamine (50 mmol), dissolved in 20 ml 95% of ethanol, was added dropwise to the stirred solution of chloroacetonitrile (50 mmol) at reflux. The mixture was stirred for 8 h at reflux. The mixture was stirred overnight at room temperature, evaporated in vacuum and the residue was purified by recrystallization from ethanol to give the title compound. Colourless blocks were grown from dichloromethane/ethanol solution.

Refinement

All the H atoms were positioned geometrically (C—H = 0.93–0.97 Å) and refined as riding with U_iso(H) = 1.2U_eq(C) or 1.5U_eq(methyl C).

Figures

Fig. 1.

The molecular structure of (I). Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.

Fig. 2.

The crystal packing for (I).

Crystal data

C8H12N4	F(000) = 176
Mr = 164.22	Dx = 1.168 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 6.3452 (13) Å	Cell parameters from 1156 reflections
b = 6.6731 (13) Å	θ = 3.1–27.8°
c = 11.077 (2) Å	µ = 0.08 mm−1
β = 95.61 (3)°	T = 293 K
V = 466.78 (16) Å3	Block, colorless
Z = 2	0.20 × 0.18 × 0.10 mm

Data collection

Rigaku Saturn CCD diffractometer	1076 independent reflections
Radiation source: rotating anode	835 reflections with I > 2σ(I)
Confocal monochromator	Rint = 0.032
ω scans	θmax = 27.9°, θmin = 6.4°
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	h = −8→5
Tmin = 0.985, Tmax = 0.992	k = −8→8
3739 measured reflections	l = −14→14

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.150	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0937P)2 + 0.0176P] where P = (Fo2 + 2Fc2)/3
1076 reflections	(Δ/σ)max < 0.001
55 parameters	Δρmax = 0.10 e Å−3
0 restraints	Δρmin = −0.15 e Å−3

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	0.06045 (14)	0.54542 (14)	0.12377 (8)	0.0464 (4)
N2	0.3536 (2)	0.9796 (2)	0.16532 (15)	0.0904 (6)
C1	−0.21559 (17)	0.52728 (19)	−0.04400 (11)	0.0497 (4)
H1A	−0.2823	0.4143	−0.0078	0.060*
H1B	−0.3249	0.6036	−0.0910	0.060*
C2	−0.10710 (17)	0.65762 (18)	0.05439 (11)	0.0499 (4)
H2A	−0.0474	0.7746	0.0184	0.060*
H2B	−0.2095	0.7030	0.1079	0.060*
C3	0.1569 (2)	0.6568 (2)	0.22683 (12)	0.0584 (4)
H3A	0.2562	0.5701	0.2741	0.070*
H3B	0.0476	0.6945	0.2779	0.070*
C4	0.2700 (2)	0.8402 (2)	0.19376 (13)	0.0647 (4)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
N1	0.0471 (6)	0.0463 (6)	0.0461 (5)	0.0023 (4)	0.0062 (4)	−0.0010 (4)
N2	0.0816 (10)	0.0743 (10)	0.1129 (13)	−0.0215 (7)	−0.0029 (9)	−0.0028 (8)
C1	0.0410 (6)	0.0516 (7)	0.0570 (7)	0.0054 (4)	0.0062 (5)	−0.0018 (5)
C2	0.0465 (6)	0.0479 (7)	0.0561 (7)	0.0087 (4)	0.0092 (5)	−0.0032 (5)
C3	0.0657 (8)	0.0575 (8)	0.0512 (7)	−0.0009 (6)	0.0013 (5)	−0.0049 (5)
C4	0.0592 (8)	0.0618 (9)	0.0707 (9)	−0.0035 (6)	−0.0057 (6)	−0.0112 (7)

Geometric parameters (Å, º)

N1—C3	1.4471 (16)	C1—H1B	0.9700
N1—C2	1.4567 (15)	C2—H2A	0.9700
N1—C1i	1.4680 (14)	C2—H2B	0.9700
N2—C4	1.1305 (19)	C3—C4	1.4824 (19)
C1—N1i	1.4681 (14)	C3—H3A	0.9700
C1—C2	1.5071 (17)	C3—H3B	0.9700
C1—H1A	0.9700
C3—N1—C2	112.51 (10)	C1—C2—H2A	109.6
C3—N1—C1i	112.82 (9)	N1—C2—H2B	109.6
C2—N1—C1i	110.49 (9)	C1—C2—H2B	109.6
N1i—C1—C2	109.89 (9)	H2A—C2—H2B	108.2
N1i—C1—H1A	109.7	N1—C3—C4	114.00 (10)
C2—C1—H1A	109.7	N1—C3—H3A	108.8
N1i—C1—H1B	109.7	C4—C3—H3A	108.8
C2—C1—H1B	109.7	N1—C3—H3B	108.8
H1A—C1—H1B	108.2	C4—C3—H3B	108.8
N1—C2—C1	110.06 (9)	H3A—C3—H3B	107.6
N1—C2—H2A	109.6	N2—C4—C3	178.07 (16)
C3—N1—C2—C1	−174.46 (8)	C2—N1—C3—C4	−64.42 (14)
C1i—N1—C2—C1	58.45 (13)	C1i—N1—C3—C4	61.41 (14)
N1i—C1—C2—N1	−58.10 (13)	N1—C3—C4—N2	13 (5)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3A···N2ii	0.97	2.57	3.427 (2)	147

Symmetry code: (ii) −x+1, y−1/2, −z+1/2.