1,4-Bis(4-chloro­benzo­yl)piperazine

Jin, H.-M.; Li, P.-F.; Li, C.-Y.; Liu, B.

doi:10.1107/S1600536807037300

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1,4-Bis(4-chlorobenzoyl)piperazine

H.-M. Jin, P.-F. Li, C.-Y. Li and B. Liu

The title compound, C₁₈H₁₆Cl₂N₂O₂, crystallizes with two half-molecules in the asymmetric unit; each molecule lies on an inversion centre. The piperazine ring adopts a chair conformation and the two chlorobenzene rings in each molecule are parallel to each other due to symmetry. The crystal packing is stabilized by C—H

O and C—H

π interactions.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807037300/bt2456sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536807037300/bt2456Isup2.hkl Contains datablock I

CCDC reference: 660198

checkCIF report

Key indicators

Single-crystal X-ray study
T = 294 K
Mean (C-C) = 0.003 Å
R factor = 0.043
wR factor = 0.132
Data-to-parameter ratio = 16.0

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No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT153_ALERT_1_C The su's on the Cell Axes   are Equal (x 100000)        200 Ang.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
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Comment top

Some amides of piperazines have been reported to exhibit marked activity in inhibiting growth of tubercle bacillus in serum (Pollard & Gray, 1953).

The title compound, C₁₈H₁₆Cl₂N₂O₂, crystallizes with two half molecules in the asymmetric unit (Figs. 1 and 2).

The piperazine rings adopt a chair-conformation and the two chlorobenzene rings are parallel to each due to symmetry.

In the crystal of (I), weak C—H···O interactions (Table 1) and a C—H···π-interaction (C18···Cg1 = 3.812 (3) Å, C18—H18B···Cg1 = 155°) stabilize the structure (Cg1 is the centroid of the C1–C6 ring).

Related literature top

For related literature, see: Pollard & Gray (1953).

Experimental top

A solution of 4-chlorobenzoyl chloride in CH₂Cl₂ was added dropwise to a suspension of 1,4-piperazine in CH₂Cl₂ at room temperature with stirring. The reaction mixture continued stirring overnight. The white solid was obtained by recrystallization from methanol. Colourless blocks of (I) were grown by natural evaporation of a methanolic solution.

Structure description top

Some amides of piperazines have been reported to exhibit marked activity in inhibiting growth of tubercle bacillus in serum (Pollard & Gray, 1953).

The title compound, C₁₈H₁₆Cl₂N₂O₂, crystallizes with two half molecules in the asymmetric unit (Figs. 1 and 2).

The piperazine rings adopt a chair-conformation and the two chlorobenzene rings are parallel to each due to symmetry.

For related literature, see: Pollard & Gray (1953).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SMART; data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures top

	Fig. 1. The molecular structure of molecule one of the title compound with the atom-numbering scheme and 30% probability displacement ellipsoids [symmetry code: -x,-y + 1,-z + 1].
	Fig. 2. The molecular structure of molecule two of the title compound with the atom-numbering scheme and 30% probability displacement ellipsoids [symmetry code: -x + 1,-y + 1,-z + 1].

1,4-Bis(4-chlorobenzoyl)piperazine top

Crystal data top

C₁₈H₁₆Cl₂N₂O₂	F(000) = 752
M_r = 363.23	D_x = 1.415 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1786 reflections
a = 11.892 (2) Å	θ = 2.5–26.2°
b = 11.413 (2) Å	µ = 0.39 mm⁻¹
c = 12.653 (2) Å	T = 294 K
β = 96.959 (3)°	Block, colourless
V = 1704.6 (5) Å³	0.16 × 0.14 × 0.12 mm
Z = 4

Data collection top

Bruker SMART 1K CCD area-detector diffractometer	3473 independent reflections
Radiation source: fine-focus sealed tube	1795 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.044
φ and ω scans	θ_max = 26.4°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −14→14
T_min = 0.940, T_max = 0.954	k = −7→14
9538 measured reflections	l = −15→15

Refinement top

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)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.132	H-atom parameters constrained
S = 1.00	w = 1/[σ²(F_o²) + (0.0605P)² + 0.0445P] where P = (F_o² + 2F_c²)/3
3473 reflections	(Δ/σ)_max = 0.002
217 parameters	Δρ_max = 0.37 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₁₈H₁₆Cl₂N₂O₂	V = 1704.6 (5) Å³
M_r = 363.23	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.892 (2) Å	µ = 0.39 mm⁻¹
b = 11.413 (2) Å	T = 294 K
c = 12.653 (2) Å	0.16 × 0.14 × 0.12 mm
β = 96.959 (3)°

Data collection top

Bruker SMART 1K CCD area-detector diffractometer	3473 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1795 reflections with I > 2σ(I)
T_min = 0.940, T_max = 0.954	R_int = 0.044
9538 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.132	H-atom parameters constrained
S = 1.00	Δρ_max = 0.37 e Å⁻³
3473 reflections	Δρ_min = −0.22 e Å⁻³
217 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.07297 (8)	1.14374 (6)	0.33438 (7)	0.0734 (3)
Cl2	0.67186 (8)	1.15311 (6)	0.41373 (7)	0.0755 (3)
O1	0.10101 (17)	0.56724 (16)	0.25514 (15)	0.0608 (6)
O2	0.73471 (16)	0.58451 (15)	0.37660 (16)	0.0604 (6)
N1	0.05304 (18)	0.55966 (16)	0.42159 (16)	0.0431 (6)
N2	0.56644 (18)	0.56438 (18)	0.43733 (19)	0.0517 (6)
C1	0.1649 (2)	0.8111 (2)	0.30465 (19)	0.0445 (6)
H1	0.2263	0.7707	0.2835	0.053*
C2	0.1644 (2)	0.9320 (2)	0.3036 (2)	0.0485 (7)
H2	0.2255	0.9731	0.2825	0.058*
C3	0.0730 (2)	0.9914 (2)	0.3340 (2)	0.0466 (7)
C4	−0.0192 (2)	0.9316 (2)	0.3633 (2)	0.0524 (7)
H4	−0.0816	0.9725	0.3819	0.063*
C5	−0.0182 (2)	0.8109 (2)	0.3649 (2)	0.0462 (7)
H5	−0.0803	0.7705	0.3848	0.055*
C6	0.0741 (2)	0.7489 (2)	0.33721 (18)	0.0393 (6)
C7	0.0774 (2)	0.6181 (2)	0.3351 (2)	0.0407 (6)
C8	0.0563 (2)	0.6076 (2)	0.52951 (19)	0.0446 (7)
H8A	0.0580	0.6925	0.5264	0.054*
H8B	0.1248	0.5815	0.5725	0.054*
C9	0.0460 (2)	0.4316 (2)	0.4195 (2)	0.0459 (7)
H9A	0.1142	0.3984	0.4578	0.055*
H9B	0.0398	0.4041	0.3464	0.055*
C10	0.6690 (2)	0.8217 (2)	0.31981 (19)	0.0444 (7)
H10	0.6819	0.7807	0.2589	0.053*
C11	0.6757 (2)	0.9420 (2)	0.3207 (2)	0.0463 (7)
H11	0.6916	0.9825	0.2604	0.056*
C12	0.6586 (2)	1.0017 (2)	0.4119 (2)	0.0443 (6)
C13	0.6332 (2)	0.9435 (2)	0.5015 (2)	0.0468 (7)
H13	0.6215	0.9849	0.5625	0.056*
C14	0.6253 (2)	0.8229 (2)	0.4990 (2)	0.0450 (7)
H14	0.6077	0.7830	0.5589	0.054*
C15	0.64333 (19)	0.7606 (2)	0.40892 (19)	0.0386 (6)
C16	0.6512 (2)	0.6301 (2)	0.4060 (2)	0.0423 (7)
C17	0.4532 (2)	0.6053 (2)	0.4531 (2)	0.0516 (7)
H17A	0.3984	0.5761	0.3962	0.062*
H17B	0.4512	0.6902	0.4510	0.062*
C18	0.5771 (2)	0.4364 (2)	0.4426 (2)	0.0574 (8)
H18A	0.6542	0.4136	0.4347	0.069*
H18B	0.5270	0.4009	0.3852	0.069*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.1044 (7)	0.0389 (4)	0.0786 (6)	−0.0003 (4)	0.0184 (5)	0.0003 (4)
Cl2	0.1046 (7)	0.0373 (4)	0.0892 (6)	−0.0095 (4)	0.0309 (5)	−0.0060 (4)
O1	0.0898 (15)	0.0487 (12)	0.0508 (13)	0.0040 (10)	0.0366 (11)	−0.0049 (9)
O2	0.0639 (13)	0.0467 (12)	0.0776 (14)	0.0110 (10)	0.0362 (11)	0.0041 (10)
N1	0.0661 (15)	0.0292 (11)	0.0363 (13)	0.0006 (10)	0.0153 (11)	−0.0010 (9)
N2	0.0502 (14)	0.0316 (12)	0.0789 (17)	0.0098 (10)	0.0300 (13)	0.0082 (11)
C1	0.0428 (16)	0.0472 (16)	0.0458 (16)	0.0024 (13)	0.0150 (13)	0.0029 (12)
C2	0.0487 (17)	0.0471 (17)	0.0503 (17)	−0.0051 (14)	0.0082 (14)	0.0069 (13)
C3	0.0599 (18)	0.0360 (15)	0.0440 (17)	−0.0011 (13)	0.0068 (14)	0.0022 (12)
C4	0.0542 (19)	0.0491 (17)	0.0563 (19)	0.0103 (14)	0.0161 (15)	0.0021 (14)
C5	0.0457 (16)	0.0434 (16)	0.0525 (17)	0.0016 (13)	0.0183 (13)	0.0040 (13)
C6	0.0426 (16)	0.0412 (15)	0.0351 (14)	0.0023 (12)	0.0087 (12)	0.0035 (11)
C7	0.0455 (16)	0.0395 (15)	0.0393 (16)	0.0025 (12)	0.0138 (13)	0.0011 (12)
C8	0.0654 (18)	0.0331 (14)	0.0362 (15)	0.0029 (13)	0.0095 (13)	−0.0031 (11)
C9	0.0659 (19)	0.0315 (14)	0.0422 (16)	0.0060 (13)	0.0150 (14)	−0.0033 (11)
C10	0.0545 (17)	0.0417 (15)	0.0396 (16)	−0.0018 (13)	0.0159 (13)	−0.0027 (12)
C11	0.0534 (17)	0.0451 (16)	0.0418 (17)	−0.0037 (13)	0.0119 (13)	0.0066 (13)
C12	0.0466 (16)	0.0359 (15)	0.0512 (17)	−0.0031 (12)	0.0098 (13)	−0.0028 (13)
C13	0.0536 (17)	0.0469 (17)	0.0417 (17)	0.0013 (13)	0.0128 (13)	−0.0107 (13)
C14	0.0517 (17)	0.0486 (16)	0.0370 (15)	0.0011 (13)	0.0140 (13)	0.0057 (12)
C15	0.0391 (15)	0.0375 (14)	0.0403 (15)	0.0010 (12)	0.0090 (12)	0.0013 (12)
C16	0.0474 (17)	0.0384 (16)	0.0441 (16)	0.0066 (13)	0.0176 (13)	0.0047 (12)
C17	0.0524 (18)	0.0352 (15)	0.070 (2)	0.0110 (13)	0.0181 (15)	0.0019 (14)
C18	0.0639 (19)	0.0373 (16)	0.076 (2)	0.0132 (14)	0.0274 (16)	0.0037 (14)

Geometric parameters (Å, º) top

Cl1—C3	1.739 (3)	C8—H8A	0.9700
Cl2—C12	1.735 (3)	C8—H8B	0.9700
O1—C7	1.228 (3)	C9—C8ⁱ	1.513 (3)
O2—C16	1.219 (3)	C9—H9A	0.9700
N1—C7	1.343 (3)	C9—H9B	0.9700
N1—C9	1.464 (3)	C10—C11	1.376 (3)
N1—C8	1.467 (3)	C10—C15	1.391 (3)
N2—C16	1.354 (3)	C10—H10	0.9300
N2—C17	1.461 (3)	C11—C12	1.377 (3)
N2—C18	1.467 (3)	C11—H11	0.9300
C1—C2	1.380 (3)	C12—C13	1.378 (3)
C1—C6	1.395 (3)	C13—C14	1.380 (3)
C1—H1	0.9300	C13—H13	0.9300
C2—C3	1.375 (4)	C14—C15	1.382 (3)
C2—H2	0.9300	C14—H14	0.9300
C3—C4	1.380 (4)	C15—C16	1.492 (3)
C4—C5	1.378 (3)	C17—C18ⁱⁱ	1.488 (4)
C4—H4	0.9300	C17—H17A	0.9700
C5—C6	1.387 (3)	C17—H17B	0.9700
C5—H5	0.9300	C18—C17ⁱⁱ	1.488 (4)
C6—C7	1.494 (3)	C18—H18A	0.9700
C8—C9ⁱ	1.513 (3)	C18—H18B	0.9700

C7—N1—C9	119.9 (2)	N1—C9—H9B	109.8
C7—N1—C8	126.1 (2)	C8ⁱ—C9—H9B	109.8
C9—N1—C8	112.61 (19)	H9A—C9—H9B	108.2
C16—N2—C17	126.4 (2)	C11—C10—C15	120.8 (2)
C16—N2—C18	120.1 (2)	C11—C10—H10	119.6
C17—N2—C18	112.8 (2)	C15—C10—H10	119.6
C2—C1—C6	120.6 (2)	C10—C11—C12	119.1 (2)
C2—C1—H1	119.7	C10—C11—H11	120.5
C6—C1—H1	119.7	C12—C11—H11	120.5
C3—C2—C1	119.5 (2)	C11—C12—C13	121.4 (2)
C3—C2—H2	120.3	C11—C12—Cl2	118.8 (2)
C1—C2—H2	120.2	C13—C12—Cl2	119.8 (2)
C2—C3—C4	120.9 (2)	C12—C13—C14	118.9 (2)
C2—C3—Cl1	119.6 (2)	C12—C13—H13	120.6
C4—C3—Cl1	119.5 (2)	C14—C13—H13	120.6
C5—C4—C3	119.5 (3)	C13—C14—C15	121.0 (2)
C5—C4—H4	120.3	C13—C14—H14	119.5
C3—C4—H4	120.3	C15—C14—H14	119.5
C4—C5—C6	120.8 (2)	C14—C15—C10	118.8 (2)
C4—C5—H5	119.6	C14—C15—C16	123.4 (2)
C6—C5—H5	119.6	C10—C15—C16	117.4 (2)
C5—C6—C1	118.7 (2)	O2—C16—N2	121.1 (2)
C5—C6—C7	122.5 (2)	O2—C16—C15	119.3 (2)
C1—C6—C7	118.7 (2)	N2—C16—C15	119.6 (2)
O1—C7—N1	122.0 (2)	N2—C17—C18ⁱⁱ	110.2 (2)
O1—C7—C6	119.8 (2)	N2—C17—H17A	109.6
N1—C7—C6	118.2 (2)	C18ⁱⁱ—C17—H17A	109.6
N1—C8—C9ⁱ	110.8 (2)	N2—C17—H17B	109.6
N1—C8—H8A	109.5	C18ⁱⁱ—C17—H17B	109.6
C9ⁱ—C8—H8A	109.5	H17A—C17—H17B	108.1
N1—C8—H8B	109.5	N2—C18—C17ⁱⁱ	109.3 (2)
C9ⁱ—C8—H8B	109.5	N2—C18—H18A	109.8
H8A—C8—H8B	108.1	C17ⁱⁱ—C18—H18A	109.8
N1—C9—C8ⁱ	109.5 (2)	N2—C18—H18B	109.8
N1—C9—H9A	109.8	C17ⁱⁱ—C18—H18B	109.8
C8ⁱ—C9—H9A	109.8	H18A—C18—H18B	108.3

C6—C1—C2—C3	−0.6 (4)	C15—C10—C11—C12	1.1 (4)
C1—C2—C3—C4	−1.4 (4)	C10—C11—C12—C13	−1.0 (4)
C1—C2—C3—Cl1	179.15 (19)	C10—C11—C12—Cl2	177.85 (19)
C2—C3—C4—C5	1.7 (4)	C11—C12—C13—C14	0.2 (4)
Cl1—C3—C4—C5	−178.8 (2)	Cl2—C12—C13—C14	−178.64 (19)
C3—C4—C5—C6	−0.1 (4)	C12—C13—C14—C15	0.5 (4)
C4—C5—C6—C1	−1.9 (4)	C13—C14—C15—C10	−0.4 (4)
C4—C5—C6—C7	−178.3 (2)	C13—C14—C15—C16	171.6 (2)
C2—C1—C6—C5	2.2 (4)	C11—C10—C15—C14	−0.5 (4)
C2—C1—C6—C7	178.8 (2)	C11—C10—C15—C16	−172.9 (2)
C9—N1—C7—O1	−4.5 (4)	C17—N2—C16—O2	−166.5 (3)
C8—N1—C7—O1	160.9 (3)	C18—N2—C16—O2	3.8 (4)
C9—N1—C7—C6	174.9 (2)	C17—N2—C16—C15	14.5 (4)
C8—N1—C7—C6	−19.6 (4)	C18—N2—C16—C15	−175.3 (2)
C5—C6—C7—O1	127.9 (3)	C14—C15—C16—O2	−124.8 (3)
C1—C6—C7—O1	−48.6 (3)	C10—C15—C16—O2	47.3 (3)
C5—C6—C7—N1	−51.5 (3)	C14—C15—C16—N2	54.3 (4)
C1—C6—C7—N1	132.0 (2)	C10—C15—C16—N2	−133.6 (3)
C7—N1—C8—C9ⁱ	136.7 (2)	C16—N2—C17—C18ⁱⁱ	−131.6 (3)
C9—N1—C8—C9ⁱ	−57.0 (3)	C18—N2—C17—C18ⁱⁱ	57.6 (3)
C7—N1—C9—C8ⁱ	−136.4 (2)	C16—N2—C18—C17ⁱⁱ	131.4 (3)
C8—N1—C9—C8ⁱ	56.2 (3)	C17—N2—C18—C17ⁱⁱ	−57.1 (3)

Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱⁱⁱ	0.93	2.42	3.350 (3)	173
C11—H11···O2^iv	0.93	2.34	3.265 (3)	170
C18—H18B···Cg1	0.97	Missing	3.812 (3)	155

Symmetry codes: (iii) −x+1/2, y+1/2, −z+1/2; (iv) −x+3/2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₆Cl₂N₂O₂
M_r	363.23
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	294
a, b, c (Å)	11.892 (2), 11.413 (2), 12.653 (2)
β (°)	96.959 (3)
V (Å³)	1704.6 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.39
Crystal size (mm)	0.16 × 0.14 × 0.12

Data collection
Diffractometer	Bruker SMART 1K CCD area-detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.940, 0.954
No. of measured, independent and observed [I > 2σ(I)] reflections	9538, 3473, 1795
R_int	0.044
(sin θ/λ)_max (Å⁻¹)	0.626

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.132, 1.00
No. of reflections	3473
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.37, −0.22

Computer programs: SMART (Bruker, 1997), SMART, SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1997), SHELXTL.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.93	2.42	3.350 (3)	173
C11—H11···O2ⁱⁱ	0.93	2.34	3.265 (3)	170
C18—H18B···Cg1	0.97	Missing	3.812 (3)	155

Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) −x+3/2, y+1/2, −z+1/2.

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