organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

4-Nitro­phenol–piperazine (2/1)

aDepartment of Physics, Anna University, Chennai 600 025, India, and bCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India
*Correspondence e-mail: shirai2011@gmail.com

(Received 20 May 2013; accepted 3 June 2013; online 8 June 2013)

In the title adduct, C6H5NO3·0.5C4H10N2, the piperazine ring possesses inversion symmetry and has a chair conformation. Its mean plane makes a dihedral angle of 65.45 (7)° with the 4-nitro­phenol ring. In the crystal, the piperazine ring is linked to two 4-nitro­phenol mol­ecules via O—H⋯N hydrogen bonds. The mol­ecules are also linked via bifurcated N—H⋯(O,O) hydrogen bonds involving the NO2 O atoms, forming a two-dimensional network lying parallel to (102). The networks are linked via C—H⋯O hydrogen bonds, forming a three-dimensional structure.

Related literature

For the biological properties of piperazine compounds, see: Foroumadi et al. (2007[Foroumadi, A., Emami, S., Mansouri, S., Javidnia, A., Saeid-Adeli, N., Shirazi, F. H. & Shafiee, A. (2007). Eur. J. Med. Chem. 42, 985-992.]); Upadhayaya et al. (2004[Upadhayaya, R. S., Sinha, N., Jain, S., Kishore, N., Chandra, R. & Arora, S. K. (2004). Bioorg. Med. Chem. 12, 2225-2238.]); Chen et al. (2006[Chen, J. J., Lu, M., Jing, Y. K. & Dong, J. H. (2006). Bioorg. Med. Chem. 14, 6539-6547.]); Cunico et al. (2009[Cunico, W., Gomes, C. R. B., Moreth, M., Manhanini, D. P., Figueiredo, I. H., Penido, C., Henriques, M. G. M. O., Varotti, F. P. & Krettli, A. U. (2009). Eur. J. Med. Chem. 44, 1363-1368.]); Smits et al. (2008[Smits, R. A., Lim, H. D., Hanzer, A., Zuiderveld, O. P., Guaita, E., Adami, M., Coruzzi, G., Leurs, R. & Esch, I. J. P. (2008). J. Med. Chem. 51, 2457-2467.]); Becker et al. (2006[Becker, O. M., Dhanoa, D. S., Marantz, Y., Chen, D., Shacham, S., Cheruku, S., Heifetz, A., Mohanty, P., Fichman, M., Sharadendu, A., Nudelman, R., Kauffman, M. & Noiman, S. (2006). J. Med. Chem. 49, 3116-3135.]).

[Scheme 1]

Experimental

Crystal data
  • C6H5NO3·0.5C4H10N2

  • Mr = 182.18

  • Monoclinic, P 21 /c

  • a = 6.1879 (2) Å

  • b = 19.9274 (7) Å

  • c = 6.9846 (2) Å

  • β = 91.199 (1)°

  • V = 861.07 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 293 K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Bruker SMART APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, U. S. A.]) Tmin = 0.968, Tmax = 0.979

  • 12570 measured reflections

  • 1763 independent reflections

  • 1437 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.111

  • S = 1.04

  • 1763 reflections

  • 126 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3A⋯N2i 0.82 1.82 2.6210 (16) 167
N2—H2A⋯O1 0.796 (19) 2.58 (2) 3.2437 (17) 141.4 (17)
N2—H2A⋯O2 0.796 (19) 2.557 (19) 3.2273 (17) 142.8 (19)
C2—H2⋯O1i 0.93 2.51 3.3428 (17) 149
C6—H6⋯O3ii 0.93 2.57 3.5035 (17) 179
Symmetry codes: (i) [x-1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, U. S. A.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, U. S. A.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Piperazine-based research has attracted considerable attention in recent years. A broad range of compounds displaying antibacterial (Foroumadi et al., 2007), antifungal (Upadhayaya et al., 2004), anticancer (Chen et al., 2006), antiparasitic (Cunico et al., 2009), antihistamin (Smits et al., 2008), and antidepressive activities (Becker et al., 2006) have been found to contain this versatile core. In view of these important properties, we have undertaken the X-ray diffraction study of the title compound.

In the title adduct, C6H5N1O3, 0.5(C4H10N2), the piperazine ring (N2/C7/C8/N2a/C7a/C8a) possesses inversion symmetry. It adopts a chair conformation and its mean plane makes a dihedral angle of 65.45 (7)° with the 4-nitrophenol ring (C1-C6).

In the crystal, the piperazine ring is linked to two 4-nitrophenol molecules via O-H···N hydrogen bonds (Table 1 and Fig 2). The molecules are also linked via bifurcated N-H···O/O hydrogen bonds, involving the NO2 O atoms, forming a two-dimensional network lying parallel to (102). These networks are linked via C-H···O hydrogen bonds forming a three-dimensional structure (Table 1).

Related literature top

For the biological properties of piperazine compounds, see: Foroumadi et al. (2007); Upadhayaya et al. (2004); Chen et al. (2006); Cunico et al. (2009); Smits et al. (2008); Becker et al. (2006).

Experimental top

Piperazine 4-nitrophenol was synthesized by mixing an equimolar mixture (1:1) of anhydrous piperazine and 4-nitrophenol in methanol. The resultant solution was stirred magnetically at room temperature and filtered into a clean beaker. The filtrate was kept in a constant temperature bath at 308 K. Yellow block-like crystals suitable for x-ray diffraction were harvested from the solution within a day.

Refinement top

The OH and C-bound H atoms were positioned geometrically and refined using a riding model: O—H = 0.82 Å, C—H = 0.93 and 0.97 Å for aryl and methylene H-atoms, respectively, with Uiso(H) = 1.5Ueq(O) and = 1.2Ueq(C,N).

Structure description top

Piperazine-based research has attracted considerable attention in recent years. A broad range of compounds displaying antibacterial (Foroumadi et al., 2007), antifungal (Upadhayaya et al., 2004), anticancer (Chen et al., 2006), antiparasitic (Cunico et al., 2009), antihistamin (Smits et al., 2008), and antidepressive activities (Becker et al., 2006) have been found to contain this versatile core. In view of these important properties, we have undertaken the X-ray diffraction study of the title compound.

In the title adduct, C6H5N1O3, 0.5(C4H10N2), the piperazine ring (N2/C7/C8/N2a/C7a/C8a) possesses inversion symmetry. It adopts a chair conformation and its mean plane makes a dihedral angle of 65.45 (7)° with the 4-nitrophenol ring (C1-C6).

In the crystal, the piperazine ring is linked to two 4-nitrophenol molecules via O-H···N hydrogen bonds (Table 1 and Fig 2). The molecules are also linked via bifurcated N-H···O/O hydrogen bonds, involving the NO2 O atoms, forming a two-dimensional network lying parallel to (102). These networks are linked via C-H···O hydrogen bonds forming a three-dimensional structure (Table 1).

For the biological properties of piperazine compounds, see: Foroumadi et al. (2007); Upadhayaya et al. (2004); Chen et al. (2006); Cunico et al. (2009); Smits et al. (2008); Becker et al. (2006).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); 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, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level (symmetry code: (a) = -x+2, -y, -z+1).
[Figure 2] Fig. 2. The crystal packing of the title compound viewed along the a axis. The N-H···O, O-H···N and C-H···O hydrogen bonds are shown as dashed lines; see Table 1 for details. The H atoms not involved in hydrogen bonding have been omitted for clarity.
4-Nitrophenol–piperazine (2/1) top
Crystal data top
C6H5NO3·0.5C4H10N2F(000) = 384
Mr = 182.18Dx = 1.405 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1763 reflections
a = 6.1879 (2) Åθ = 2.0–26.4°
b = 19.9274 (7) ŵ = 0.11 mm1
c = 6.9846 (2) ÅT = 293 K
β = 91.199 (1)°Block, yellow
V = 861.07 (5) Å30.30 × 0.25 × 0.20 mm
Z = 4
Data collection top
Bruker SMART APEXII area-detector
diffractometer
1763 independent reflections
Radiation source: fine-focus sealed tube1437 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ω and φ scansθmax = 26.4°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 77
Tmin = 0.968, Tmax = 0.979k = 2424
12570 measured reflectionsl = 88
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.111 w = 1/[σ2(Fo2) + (0.0534P)2 + 0.1751P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
1763 reflectionsΔρmax = 0.19 e Å3
126 parametersΔρmin = 0.17 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.022 (4)
Crystal data top
C6H5NO3·0.5C4H10N2V = 861.07 (5) Å3
Mr = 182.18Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.1879 (2) ŵ = 0.11 mm1
b = 19.9274 (7) ÅT = 293 K
c = 6.9846 (2) Å0.30 × 0.25 × 0.20 mm
β = 91.199 (1)°
Data collection top
Bruker SMART APEXII area-detector
diffractometer
1763 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
1437 reflections with I > 2σ(I)
Tmin = 0.968, Tmax = 0.979Rint = 0.024
12570 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.111H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.19 e Å3
1763 reflectionsΔρmin = 0.17 e Å3
126 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
xyzUiso*/Ueq
C10.3284 (2)0.39314 (6)0.57841 (18)0.0431 (3)
C20.2308 (2)0.33121 (6)0.61501 (19)0.0446 (3)
H20.09290.33000.66540.053*
C30.3365 (2)0.27233 (6)0.57715 (19)0.0436 (3)
H30.27110.23130.60190.052*
C40.5409 (2)0.27456 (6)0.50202 (18)0.0412 (3)
C50.6389 (2)0.33516 (7)0.45997 (18)0.0460 (3)
H50.77560.33590.40720.055*
C60.5330 (2)0.39403 (7)0.4966 (2)0.0474 (3)
H60.59740.43480.46700.057*
C70.8041 (2)0.00321 (8)0.3919 (2)0.0604 (4)
H7A0.72740.00850.27030.073*
H7B0.69820.00240.49110.073*
C81.0620 (3)0.06407 (7)0.5674 (2)0.0615 (4)
H8A0.96050.07070.66970.074*
H8B1.15450.10330.56180.074*
N10.65536 (19)0.21262 (6)0.46944 (16)0.0506 (3)
N20.9439 (2)0.05619 (6)0.38520 (18)0.0515 (3)
O10.84102 (19)0.21550 (6)0.4113 (2)0.0764 (4)
O20.56486 (19)0.15891 (5)0.50020 (17)0.0672 (3)
O30.23383 (18)0.45125 (5)0.61778 (16)0.0628 (3)
H3A0.13300.44470.68980.094*
H2A0.867 (3)0.0873 (10)0.362 (3)0.071 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0508 (7)0.0362 (6)0.0425 (7)0.0028 (5)0.0080 (5)0.0010 (5)
C20.0394 (6)0.0439 (7)0.0507 (7)0.0000 (5)0.0092 (5)0.0019 (5)
C30.0464 (7)0.0370 (6)0.0473 (7)0.0033 (5)0.0015 (6)0.0022 (5)
C40.0439 (7)0.0420 (7)0.0376 (6)0.0076 (5)0.0014 (5)0.0052 (5)
C50.0397 (7)0.0547 (8)0.0438 (7)0.0013 (5)0.0079 (5)0.0017 (6)
C60.0521 (8)0.0420 (7)0.0486 (7)0.0058 (6)0.0106 (6)0.0011 (5)
C70.0445 (7)0.0688 (10)0.0680 (9)0.0099 (7)0.0014 (6)0.0101 (8)
C80.0785 (10)0.0362 (7)0.0703 (10)0.0139 (7)0.0146 (8)0.0050 (6)
N10.0530 (7)0.0529 (7)0.0458 (6)0.0152 (5)0.0031 (5)0.0079 (5)
N20.0537 (7)0.0356 (6)0.0658 (8)0.0096 (5)0.0141 (6)0.0094 (5)
O10.0564 (7)0.0762 (8)0.0972 (10)0.0210 (6)0.0138 (6)0.0163 (6)
O20.0812 (8)0.0428 (6)0.0776 (8)0.0125 (5)0.0034 (6)0.0018 (5)
O30.0740 (7)0.0385 (5)0.0772 (8)0.0080 (5)0.0329 (6)0.0014 (5)
Geometric parameters (Å, º) top
C1—O31.3290 (15)C7—N21.4673 (18)
C1—C61.3995 (19)C7—C8i1.493 (2)
C1—C21.4000 (17)C7—H7A0.9700
C2—C31.3720 (18)C7—H7B0.9700
C2—H20.9300C8—N21.463 (2)
C3—C41.3799 (19)C8—C7i1.493 (2)
C3—H30.9300C8—H8A0.9700
C4—C51.3855 (18)C8—H8B0.9700
C4—N11.4434 (16)N1—O11.2279 (16)
C5—C61.3706 (18)N1—O21.2290 (16)
C5—H50.9300N2—H2A0.80 (2)
C6—H60.9300O3—H3A0.8200
O3—C1—C6118.65 (11)N2—C7—H7A109.7
O3—C1—C2122.45 (12)C8i—C7—H7A109.7
C6—C1—C2118.90 (11)N2—C7—H7B109.7
C3—C2—C1120.60 (12)C8i—C7—H7B109.7
C3—C2—H2119.7H7A—C7—H7B108.2
C1—C2—H2119.7N2—C8—C7i110.09 (12)
C2—C3—C4119.37 (12)N2—C8—H8A109.6
C2—C3—H3120.3C7i—C8—H8A109.6
C4—C3—H3120.3N2—C8—H8B109.6
C3—C4—C5121.15 (11)C7i—C8—H8B109.6
C3—C4—N1119.28 (12)H8A—C8—H8B108.2
C5—C4—N1119.57 (12)O1—N1—O2122.10 (12)
C6—C5—C4119.55 (12)O1—N1—C4118.54 (12)
C6—C5—H5120.2O2—N1—C4119.36 (12)
C4—C5—H5120.2C8—N2—C7110.05 (11)
C5—C6—C1120.37 (12)C8—N2—H2A112.3 (14)
C5—C6—H6119.8C7—N2—H2A106.6 (14)
C1—C6—H6119.8C1—O3—H3A109.5
N2—C7—C8i109.63 (11)
O3—C1—C2—C3178.17 (12)O3—C1—C6—C5177.78 (12)
C6—C1—C2—C32.1 (2)C2—C1—C6—C52.5 (2)
C1—C2—C3—C40.1 (2)C3—C4—N1—O1176.52 (12)
C2—C3—C4—C51.5 (2)C5—C4—N1—O12.59 (19)
C2—C3—C4—N1177.55 (11)C3—C4—N1—O23.58 (19)
C3—C4—C5—C61.2 (2)C5—C4—N1—O2177.31 (11)
N1—C4—C5—C6177.93 (11)C7i—C8—N2—C759.04 (16)
C4—C5—C6—C10.9 (2)C8i—C7—N2—C858.77 (17)
Symmetry code: (i) x+2, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···N2ii0.821.822.6210 (16)167
N2—H2A···O10.796 (19)2.58 (2)3.2437 (17)141.4 (17)
N2—H2A···O20.796 (19)2.557 (19)3.2273 (17)142.8 (19)
C2—H2···O1ii0.932.513.3428 (17)149
C6—H6···O3iii0.932.573.5035 (17)179
Symmetry codes: (ii) x1, y+1/2, z+1/2; (iii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC6H5NO3·0.5C4H10N2
Mr182.18
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)6.1879 (2), 19.9274 (7), 6.9846 (2)
β (°) 91.199 (1)
V3)861.07 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker SMART APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2008)
Tmin, Tmax0.968, 0.979
No. of measured, independent and
observed [I > 2σ(I)] reflections
12570, 1763, 1437
Rint0.024
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.111, 1.04
No. of reflections1763
No. of parameters126
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.19, 0.17

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···N2i0.821.822.6210 (16)167
N2—H2A···O10.796 (19)2.58 (2)3.2437 (17)141.4 (17)
N2—H2A···O20.796 (19)2.557 (19)3.2273 (17)142.8 (19)
C2—H2···O1i0.932.513.3428 (17)149
C6—H6···O3ii0.932.573.5035 (17)179
Symmetry codes: (i) x1, y+1/2, z+1/2; (ii) x+1, y+1, z+1.
 

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection. TS and DV thank the UGC (SAP–CAS) for the departmental facilities. TS also thanks DST Inspire for a fellowship.

References

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