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

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ISSN: 2056-9890

1-Tosyl-4-[2-(tri­fluoro­meth­yl)benz­yl]piperazine

aDepartment of Studies and Research in Chemistry, Tumkur University, Tumkur, Karnataka 572 103, India, bDepartment of Physics, Karnatak University, Dharwad, Karnataka 580 003, India, cDepartment of Studies and Research in Chemistry, UCS, Tumkur University, Tumkur, Karnataka 572 103, India, and dDepartment of Studies and Research in Physics, UCS, Tumkur University, Tumkur, Karnataka 572 103, India
*Correspondence e-mail: drsreenivasa@yahoo.co.in

(Received 24 December 2012; accepted 4 January 2013; online 16 January 2013)

In the crystal structure of the title compound, C19H21F3N2O2S, the piperazine ring adopts a chair conformation. The dihedral angles between the mean plane of the piperazine ring and the tosyl and trifluoro­methyl­phenyl rings are 74.52 (3) and 68.30 (2)°, respectively. The sulfonamide N atom deviates from the plane defined by the three attached atoms by 0.327 (1) Å. The crystal structure is stabilized by weak C—H⋯π inter­actions.

Related literature

For the synthesis, characterization and biological activity of piperazine and its derivatives, see: Gan et al. (2009a[Gan, L.-L., Cai, J.-L. & Zhou, C.-H. (2009a). Chin. Pharm. J. 44, 1361-1368.],b[Gan, L.-L., Lu, Y.-H. & Zhou, C.-H. (2009b). Chin. J. Biochem. Pharm. 30, 127-131.])

[Scheme 1]

Experimental

Crystal data
  • C19H21F3N2O2S

  • Mr = 398.44

  • Triclinic, [P \overline 1]

  • a = 9.5044 (3) Å

  • b = 9.8389 (3) Å

  • c = 12.1473 (4) Å

  • α = 72.036 (1)°

  • β = 77.024 (1)°

  • γ = 62.384 (1)°

  • V = 952.96 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.22 mm−1

  • T = 296 K

  • 0.28 × 0.26 × 0.24 mm

Data collection
  • Bruker APEXII diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SADABS, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.942, Tmax = 0.950

  • 18514 measured reflections

  • 3359 independent reflections

  • 2981 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.119

  • S = 1.08

  • 3359 reflections

  • 245 parameters

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.53 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the benzene ring of the trifluoro­methyl­phenyl group (C1–C6).

D—H⋯A D—H H⋯A DA D—H⋯A
C11—H11ACgi 0.97 2.84 (1) 3.670 (2) 144
Symmetry code: (i) -x, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SADABS, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT-Plus (Bruker, 2009[Bruker (2009). APEX2, SADABS, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus and XPREP (Bruker, 2009[Bruker (2009). APEX2, SADABS, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Numerous piperazine derivatives like aryl amide, sulfonamides, Mannich bases, Schiff bases, thiazolidinones, azetidinones, imidazolinones have shown a wide spectrum of biological activities viz. anti-inflammatory, antibacterial, antimalarial, anticonvulsant, antipyretic, antitumor, anthelmintics, analgesic, antidepressant, antifungal, antitubercular, anticancer, antidiabetic (Gan et al., 2009a,b). Keeping this in mind, we synthesized the title compound and here we report its crystal structure.

Related literature top

For the synthesis, characterization and biological activity of piperazine and its derivatives, see: Gan et al. (2009a,b)

Experimental top

A mixture of 1-tosylpiperazine (0.01 mmol), potassium carbonate (0.03 mmol) and 2-trifluoromethylbenzyl bromide (0.01 mmol) was added into dry acetonitrile (5 ml). The mixture was stirred at 85°C for 8 h. The reaction was monitored by TLC. Solvent was removed by vacuum distillation and the crude product obtained was purified by column chromatography using 230–400 silica gel and petroleum ether/ethyl acetate as eluent. Single crystals of the title compound were obtained from a mixture of petroleum ether/ethyl acetate (7:3) by slow evaporation technique.

Refinement top

All H atoms were included in calculated positions with C—H bond distances 0.93–0.97 Å and refined in a riding model approximation with Uiso(H) = 1.5Ueq(Cmethyl) and Uĩso(H) = 1.2Ueq(C) for the remaining H atoms.

Computing details top

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

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Molecular packing of the title compound. C—H···π interactions are shown as dashed lines.
1-(4-Methylphenylsulfonyl)-4-[2-(trifluoromethyl)benzyl]piperazine top
Crystal data top
C19H21F3N2O2SF(000) = 416
Mr = 398.44prism
Triclinic, P1Dx = 1.389 Mg m3
Hall symbol: -P 1Melting point: 455 K
a = 9.5044 (3) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.8389 (3) ÅCell parameters from 3359 reflections
c = 12.1473 (4) Åθ = 1.8–25.0°
α = 72.036 (1)°µ = 0.22 mm1
β = 77.024 (1)°T = 296 K
γ = 62.384 (1)°Prism, colourless
V = 952.96 (5) Å30.28 × 0.26 × 0.24 mm
Z = 2
Data collection top
Bruker APEXII
diffractometer
2981 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.023
Graphite monochromatorθmax = 25.0°, θmin = 1.8°
ϕ and ω scansh = 1111
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
k = 1111
Tmin = 0.942, Tmax = 0.950l = 1414
18514 measured reflections2981 standard reflections every 3359 reflections
3359 independent reflections intensity decay: 0.6%
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.119H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0669P)2 + 0.2061P]
where P = (Fo2 + 2Fc2)/3
3359 reflections(Δ/σ)max = 0.001
245 parametersΔρmax = 0.18 e Å3
0 restraintsΔρmin = 0.53 e Å3
0 constraints
Crystal data top
C19H21F3N2O2Sγ = 62.384 (1)°
Mr = 398.44V = 952.96 (5) Å3
Triclinic, P1Z = 2
a = 9.5044 (3) ÅMo Kα radiation
b = 9.8389 (3) ŵ = 0.22 mm1
c = 12.1473 (4) ÅT = 296 K
α = 72.036 (1)°0.28 × 0.26 × 0.24 mm
β = 77.024 (1)°
Data collection top
Bruker APEXII
diffractometer
2981 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
Rint = 0.023
Tmin = 0.942, Tmax = 0.9502981 standard reflections every 3359 reflections
18514 measured reflections intensity decay: 0.6%
3359 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0420 restraints
wR(F2) = 0.119H-atom parameters constrained
S = 1.08Δρmax = 0.18 e Å3
3359 reflectionsΔρmin = 0.53 e Å3
245 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
xyzUiso*/Ueq
C10.1973 (2)0.79085 (19)1.04506 (16)0.0524 (4)
H10.14130.80510.97230.063*
C20.3565 (2)0.8200 (2)1.0527 (2)0.0650 (5)
H20.40540.85120.98520.078*
C30.4417 (2)0.8030 (2)1.1589 (2)0.0692 (6)
H30.54940.82691.16370.083*
C40.3681 (2)0.7507 (2)1.25786 (19)0.0601 (5)
H40.42580.73821.33010.072*
C50.2083 (2)0.71618 (19)1.25148 (15)0.0484 (4)
C60.12093 (19)0.74094 (18)1.14417 (14)0.0446 (4)
C70.1307 (2)0.6477 (3)1.36242 (17)0.0662 (5)
C80.0483 (2)0.7240 (3)1.13458 (15)0.0570 (4)
H8A0.04650.80481.16540.068*
H8B0.11200.62211.18190.068*
C90.1988 (2)0.5868 (2)0.98362 (15)0.0533 (4)
H9A0.12080.54470.99570.064*
H9B0.28350.51241.03280.064*
C100.2667 (2)0.6058 (2)0.85784 (15)0.0512 (4)
H10A0.31900.50410.83780.061*
H10B0.18180.67560.80790.061*
C110.3078 (2)0.8246 (2)0.87272 (15)0.0549 (4)
H11A0.22310.89980.82370.066*
H11B0.38620.86580.86170.066*
C120.2407 (2)0.8003 (2)0.99864 (16)0.0572 (4)
H12A0.32650.72751.04730.069*
H12B0.19080.90001.02130.069*
C130.39911 (19)0.7588 (2)0.60451 (14)0.0494 (4)
C140.3464 (2)0.6848 (2)0.55409 (16)0.0586 (5)
H140.37240.57760.58260.070*
C150.2560 (2)0.7693 (3)0.46208 (17)0.0650 (5)
H150.22110.71870.42840.078*
C160.2156 (2)0.9293 (3)0.41834 (15)0.0607 (5)
C170.2694 (2)1.0018 (2)0.46948 (16)0.0623 (5)
H170.24401.10880.44070.075*
C180.3601 (2)0.9183 (2)0.56233 (16)0.0564 (4)
H180.39470.96870.59640.068*
C190.1146 (3)1.0231 (4)0.3176 (2)0.0932 (8)
H19A0.00381.06160.34640.140*
H19B0.13640.95670.26650.140*
H19C0.13941.11080.27580.140*
N10.12372 (17)0.73734 (17)1.01560 (12)0.0492 (3)
N20.38211 (16)0.67220 (16)0.84130 (12)0.0482 (3)
O10.58136 (16)0.48817 (17)0.72513 (13)0.0758 (4)
O20.60748 (16)0.7253 (2)0.72858 (12)0.0771 (4)
F10.05597 (17)0.7266 (2)1.37482 (11)0.0944 (5)
F20.23300 (18)0.6445 (2)1.45635 (11)0.1050 (5)
F30.02138 (19)0.49998 (18)1.36833 (12)0.1020 (5)
S10.51074 (5)0.65163 (6)0.72555 (4)0.05661 (18)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0562 (10)0.0455 (9)0.0529 (10)0.0191 (8)0.0149 (8)0.0053 (7)
C20.0602 (11)0.0482 (10)0.0846 (14)0.0144 (9)0.0344 (11)0.0076 (9)
C30.0427 (10)0.0585 (11)0.1037 (17)0.0164 (9)0.0127 (11)0.0198 (11)
C40.0473 (10)0.0564 (10)0.0756 (13)0.0231 (8)0.0041 (9)0.0199 (9)
C50.0462 (9)0.0456 (9)0.0517 (9)0.0183 (7)0.0002 (7)0.0144 (7)
C60.0433 (8)0.0414 (8)0.0475 (9)0.0150 (7)0.0060 (7)0.0121 (7)
C70.0612 (12)0.0861 (15)0.0477 (10)0.0313 (11)0.0032 (9)0.0172 (10)
C80.0502 (10)0.0831 (13)0.0427 (9)0.0317 (9)0.0003 (7)0.0193 (9)
C90.0600 (10)0.0541 (10)0.0493 (9)0.0324 (9)0.0011 (8)0.0084 (7)
C100.0595 (10)0.0490 (9)0.0479 (9)0.0269 (8)0.0021 (8)0.0139 (7)
C110.0650 (11)0.0588 (10)0.0516 (10)0.0377 (9)0.0018 (8)0.0115 (8)
C120.0670 (11)0.0690 (11)0.0508 (10)0.0406 (10)0.0005 (8)0.0199 (8)
C130.0414 (8)0.0590 (10)0.0397 (8)0.0213 (8)0.0039 (7)0.0068 (7)
C140.0609 (11)0.0564 (10)0.0553 (10)0.0245 (9)0.0012 (8)0.0146 (8)
C150.0638 (12)0.0822 (14)0.0566 (11)0.0333 (11)0.0024 (9)0.0254 (10)
C160.0500 (10)0.0817 (14)0.0409 (9)0.0236 (9)0.0002 (7)0.0119 (9)
C170.0643 (12)0.0602 (11)0.0505 (10)0.0255 (9)0.0038 (9)0.0002 (8)
C180.0604 (11)0.0619 (11)0.0494 (10)0.0326 (9)0.0038 (8)0.0068 (8)
C190.0775 (15)0.124 (2)0.0571 (13)0.0275 (15)0.0203 (11)0.0076 (13)
N10.0514 (8)0.0605 (8)0.0421 (7)0.0291 (7)0.0010 (6)0.0160 (6)
N20.0475 (8)0.0526 (8)0.0414 (7)0.0232 (6)0.0020 (6)0.0054 (6)
O10.0583 (8)0.0634 (8)0.0647 (9)0.0005 (7)0.0021 (6)0.0076 (6)
O20.0539 (8)0.1138 (12)0.0621 (8)0.0461 (8)0.0073 (6)0.0008 (8)
F10.0980 (10)0.1560 (14)0.0594 (8)0.0745 (10)0.0026 (7)0.0361 (8)
F20.0923 (10)0.1675 (15)0.0502 (7)0.0651 (10)0.0168 (7)0.0202 (8)
F30.1030 (11)0.0919 (10)0.0645 (8)0.0078 (8)0.0260 (7)0.0014 (7)
S10.0409 (3)0.0670 (3)0.0460 (3)0.0177 (2)0.00155 (18)0.0027 (2)
Geometric parameters (Å, º) top
C1—C61.384 (2)C11—N21.464 (2)
C1—C21.390 (3)C11—C121.510 (2)
C1—H10.9300C11—H11A0.9700
C2—C31.368 (3)C11—H11B0.9700
C2—H20.9300C12—N11.456 (2)
C3—C41.364 (3)C12—H12A0.9700
C3—H30.9300C12—H12B0.9700
C4—C51.384 (2)C13—C141.381 (3)
C4—H40.9300C13—C181.382 (3)
C5—C61.398 (2)C13—S11.7625 (17)
C5—C71.496 (3)C14—C151.369 (3)
C6—C81.519 (2)C14—H140.9300
C7—F21.325 (2)C15—C161.386 (3)
C7—F11.328 (3)C15—H150.9300
C7—F31.329 (3)C16—C171.383 (3)
C8—N11.458 (2)C16—C191.510 (3)
C8—H8A0.9700C17—C181.378 (3)
C8—H8B0.9700C17—H170.9300
C9—N11.451 (2)C18—H180.9300
C9—C101.510 (2)C19—H19A0.9600
C9—H9A0.9700C19—H19B0.9600
C9—H9B0.9700C19—H19C0.9600
C10—N21.468 (2)N2—S11.6391 (14)
C10—H10A0.9700O2—S11.4223 (15)
C10—H10B0.9700S1—O11.4282 (15)
C6—C1—C2120.91 (18)N2—C11—H11B110.0
C6—C1—H1119.5C12—C11—H11B110.0
C2—C1—H1119.5H11A—C11—H11B108.4
C3—C2—C1120.35 (18)N1—C12—C11110.19 (14)
C3—C2—H2119.8N1—C12—H12A109.6
C1—C2—H2119.8C11—C12—H12A109.6
C4—C3—C2119.77 (18)N1—C12—H12B109.6
C4—C3—H3120.1C11—C12—H12B109.6
C2—C3—H3120.1H12A—C12—H12B108.1
C3—C4—C5120.43 (18)C14—C13—C18120.00 (17)
C3—C4—H4119.8C14—C13—S1120.06 (14)
C5—C4—H4119.8C18—C13—S1119.91 (14)
C4—C5—C6120.86 (17)C15—C14—C13119.93 (18)
C4—C5—C7118.11 (16)C15—C14—H14120.0
C6—C5—C7121.01 (15)C13—C14—H14120.0
C1—C6—C5117.53 (15)C14—C15—C16121.02 (18)
C1—C6—C8120.23 (15)C14—C15—H15119.5
C5—C6—C8122.15 (15)C16—C15—H15119.5
F2—C7—F1105.93 (17)C17—C16—C15118.43 (18)
F2—C7—F3106.64 (18)C17—C16—C19120.4 (2)
F1—C7—F3106.07 (18)C15—C16—C19121.1 (2)
F2—C7—C5113.14 (17)C18—C17—C16121.17 (18)
F1—C7—C5113.06 (17)C18—C17—H17119.4
F3—C7—C5111.48 (16)C16—C17—H17119.4
N1—C8—C6113.17 (14)C17—C18—C13119.45 (17)
N1—C8—H8A108.9C17—C18—H18120.3
C6—C8—H8A108.9C13—C18—H18120.3
N1—C8—H8B108.9C16—C19—H19A109.5
C6—C8—H8B108.9C16—C19—H19B109.5
H8A—C8—H8B107.8H19A—C19—H19B109.5
N1—C9—C10110.58 (13)C16—C19—H19C109.5
N1—C9—H9A109.5H19A—C19—H19C109.5
C10—C9—H9A109.5H19B—C19—H19C109.5
N1—C9—H9B109.5C9—N1—C12109.73 (14)
C10—C9—H9B109.5C9—N1—C8111.63 (14)
H9A—C9—H9B108.1C12—N1—C8111.32 (13)
N2—C10—C9108.49 (13)C11—N2—C10111.46 (13)
N2—C10—H10A110.0C11—N2—S1118.22 (11)
C9—C10—H10A110.0C10—N2—S1116.83 (11)
N2—C10—H10B110.0O2—S1—O1120.28 (9)
C9—C10—H10B110.0O2—S1—N2106.27 (8)
H10A—C10—H10B108.4O1—S1—N2106.46 (8)
N2—C11—C12108.27 (14)O2—S1—C13108.64 (8)
N2—C11—H11A110.0O1—S1—C13107.92 (9)
C12—C11—H11A110.0N2—S1—C13106.48 (7)
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the benzene ring of the trifluoromethylphenyl group (C1–C6).
D—H···AD—HH···AD···AD—H···A
C11—H11A···Cgi0.972.84 (1)3.670 (2)144
Symmetry code: (i) x, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC19H21F3N2O2S
Mr398.44
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)9.5044 (3), 9.8389 (3), 12.1473 (4)
α, β, γ (°)72.036 (1), 77.024 (1), 62.384 (1)
V3)952.96 (5)
Z2
Radiation typeMo Kα
µ (mm1)0.22
Crystal size (mm)0.28 × 0.26 × 0.24
Data collection
DiffractometerBruker APEXII
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.942, 0.950
No. of measured, independent and
observed [I > 2σ(I)] reflections
18514, 3359, 2981
Rint0.023
(sin θ/λ)max1)0.594
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.119, 1.08
No. of reflections3359
No. of parameters245
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.18, 0.53

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

Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the benzene ring of the trifluoromethylphenyl group (C1–C6).
D—H···AD—HH···AD···AD—H···A
C11—H11A···Cgi0.972.840 (2)3.670 (2)144
Symmetry code: (i) x, y+1, z+1.
 

Acknowledgements

The authors thank Dr S. C. Sharma, Vice Chancellor, Tumkur University, Tumkur, for his constant encouragement. JT thanks DST, New Delhi, for the SCXRD facility under a PURSE Grant (SR/S9/Z-23/2008/11, 2009) at USIC, Karnatak University.

References

First citationBruker (2009). APEX2, SADABS, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.
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