Ethyl 4-(phenyl­sulfon­yl)piperazine-1-carboxyl­ate

Al-Dajani, M.T.M.; Adballah, H.H.; Mohamed, N.; Hemamalini, M.; Fun, H.-K.

doi:10.1107/S1600536811033162

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page o2401

doi:10.1107/S1600536811033162

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Ethyl 4-(phenylsulfonyl)piperazine-1-carboxylate

Mohammad T.M. Al-Dajani,^a Hassan H. Adballah,^b Nornisah Mohamed,^a Madhukar Hemamalini ^c and Hoong-Kun Fun ^c ^*‡

^aSchool of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and ^cX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 15 August 2011; accepted 16 August 2011; online 27 August 2011)

In the title compound, C₁₃H₁₈N₂O₄S, the piperazine ring adopts a chair conformation. The dihedral angle between the least-squares planes through the piperazine and benzene rings is 73.23 (10)°. In the crystal, there are no classical hydrogen bonds but stabilization is provided by weak C—H⋯π interactions.

Related literature

For the biological activity of piperazine derivatives, see: Emami et al. (2006 ); Foroumadi et al. (2007 ). For puckering parameters, see: Cremer & Pople (1975 ).

Experimental

Crystal data

C₁₃H₁₈N₂O₄S
M_r = 298.35
Monoclinic, P 2₁ /c
a = 6.1433 (5) Å
b = 20.5966 (17) Å
c = 12.5626 (8) Å
β = 114.026 (3)°
V = 1451.84 (19) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 296 K
0.58 × 0.38 × 0.17 mm

Data collection

Bruker APEXII DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.875, T_max = 0.961
16507 measured reflections
4255 independent reflections
3400 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.158
S = 1.04
4255 reflections
182 parameters
H-atom parameters constrained
Δρ_max = 0.60 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H13A⋯Cg1ⁱ	0.96	2.97	3.900 (4)	165
Symmetry code: (i) -x-1, -y, -z+1.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811033162/tk2781sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811033162/tk2781Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811033162/tk2781Isup3.cml

checkCIF report

Comment top

Piperazine derivatives are used as antibiotic drugs, e.g. Norfloxacin, Ciprofloxacin, Enoxacin, Ofloxacin and Levofloxacine (Emami et al., 2006; Foroumadi et al., 2007). Due to the biological importance of piperazine, herein, we present the crystal and molecular structure of the title compound, (I).

The piperazine (N1–N2/C7–C10) ring in (I), Fig. 1, adopts a chair conformation [puckering parameters: Q = 0.5682 (18) Å, θ = 2.56 (17) ° and ϕ = 349 (4) ° (Cremer & Pople, 1975)] with atoms N1 and C9 deviating by 0.253 (1) and 0.223 (2) Å from the least-squares plane defined by the remaining atoms (N2/C7,C8/C10) in the ring. The dihedral angle between the piperazine (N1–N2/C7–C10) ring and the benzene (C1–C6) ring is 73.23 (10) °.

In the crystal structure (Fig. 2), there are no classical hydrogen bonds but stabilization is provided by weak C—H···π interactions (Table 1).

Related literature top

For the biological activity of piperazine derivatives, see: Emami et al. (2006); Foroumadi et al. (2007). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

In a round bottom flask, 25ml of toluene was mixed with benzenesulfonyl chloride (0.01 mol, 1.0 g) with stirring. Ethyl-1-piperazine-carboxylate (0.01 mol, 1.7ml) dissolved in toluene was then added drop wise. The reaction mixture was refluxed for 30 min. The yellow precipitate formed was washed with alkaline water. The precipitate was then dissolved in methanol at room temperature. After few days, yellow crystals were formed by slow evaporation.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I), showing the atom labelling scheme and 50% probability displacement ellipsoids.
	Fig. 2. A view of the crystal packing in (I).

Ethyl 4-(phenylsulfonyl)piperazine-1-carboxylate top

Crystal data top

C₁₃H₁₈N₂O₄S	F(000) = 632
M_r = 298.35	D_x = 1.365 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5957 reflections
a = 6.1433 (5) Å	θ = 2.7–29.7°
b = 20.5966 (17) Å	µ = 0.24 mm⁻¹
c = 12.5626 (8) Å	T = 296 K
β = 114.026 (3)°	Block, yellow
V = 1451.84 (19) Å³	0.58 × 0.38 × 0.17 mm
Z = 4

Data collection top

Bruker APEXII DUO CCD area-detector diffractometer	4255 independent reflections
Radiation source: fine-focus sealed tube	3400 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ϕ and ω scans	θ_max = 30.1°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→8
T_min = 0.875, T_max = 0.961	k = −29→24
16507 measured reflections	l = −17→17

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.158	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0887P)² + 0.3986P] where P = (F_o² + 2F_c²)/3
4255 reflections	(Δ/σ)_max = 0.001
182 parameters	Δρ_max = 0.60 e Å⁻³
0 restraints	Δρ_min = −0.30 e Å⁻³

Crystal data top

C₁₃H₁₈N₂O₄S	V = 1451.84 (19) Å³
M_r = 298.35	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 6.1433 (5) Å	µ = 0.24 mm⁻¹
b = 20.5966 (17) Å	T = 296 K
c = 12.5626 (8) Å	0.58 × 0.38 × 0.17 mm
β = 114.026 (3)°

Data collection top

Bruker APEXII DUO CCD area-detector diffractometer	4255 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	3400 reflections with I > 2σ(I)
T_min = 0.875, T_max = 0.961	R_int = 0.023
16507 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	0 restraints
wR(F²) = 0.158	H-atom parameters constrained
S = 1.04	Δρ_max = 0.60 e Å⁻³
4255 reflections	Δρ_min = −0.30 e Å⁻³
182 parameters

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
S1	0.36299 (7)	−0.120155 (19)	0.94030 (3)	0.03858 (14)
O1	0.3060 (3)	−0.12052 (6)	1.04000 (10)	0.0517 (3)
O2	0.6074 (2)	−0.12032 (7)	0.95617 (12)	0.0547 (3)
O3	−0.1090 (3)	0.07756 (8)	0.52229 (12)	0.0659 (4)
O4	−0.3840 (2)	0.07205 (8)	0.59831 (12)	0.0605 (4)
N1	0.2424 (2)	−0.05482 (6)	0.86538 (10)	0.0346 (3)
N2	−0.0094 (2)	0.04239 (7)	0.70682 (12)	0.0412 (3)
C1	0.0247 (4)	−0.21553 (9)	0.86231 (18)	0.0544 (4)
H1A	−0.0323	−0.1999	0.9156	0.065*
C2	−0.0839 (4)	−0.26783 (11)	0.7902 (2)	0.0749 (7)
H2A	−0.2149	−0.2877	0.7957	0.090*
C3	−0.0001 (5)	−0.29053 (11)	0.7108 (2)	0.0813 (8)
H3A	−0.0749	−0.3255	0.6630	0.098*
C4	0.1924 (5)	−0.26197 (12)	0.7021 (2)	0.0785 (7)
H4A	0.2477	−0.2776	0.6482	0.094*
C5	0.3063 (4)	−0.20992 (11)	0.77261 (18)	0.0595 (5)
H5A	0.4375	−0.1905	0.7666	0.071*
C6	0.2208 (3)	−0.18732 (8)	0.85247 (14)	0.0421 (3)
C7	−0.0086 (3)	−0.04191 (8)	0.84341 (13)	0.0376 (3)
H7A	−0.0340	−0.0501	0.9135	0.045*
H7B	−0.1126	−0.0704	0.7824	0.045*
C8	−0.0652 (3)	0.02844 (8)	0.80650 (14)	0.0406 (3)
H8A	−0.2328	0.0367	0.7862	0.049*
H8B	0.0271	0.0567	0.8708	0.049*
C9	0.2364 (3)	0.02842 (9)	0.72652 (16)	0.0472 (4)
H9A	0.3431	0.0565	0.7873	0.057*
H9B	0.2594	0.0367	0.6558	0.057*
C10	0.2931 (3)	−0.04207 (9)	0.76225 (14)	0.0423 (3)
H10A	0.1969	−0.0703	0.6987	0.051*
H10B	0.4597	−0.0508	0.7804	0.051*
C11	−0.1625 (3)	0.06530 (8)	0.60275 (14)	0.0436 (4)
C12	−0.5669 (4)	0.09306 (12)	0.48616 (18)	0.0637 (5)
H12A	−0.5300	0.0763	0.4233	0.076*
H12C	−0.7206	0.0759	0.4769	0.076*
C13	−0.5775 (7)	0.16308 (16)	0.4804 (3)	0.1174 (13)
H13A	−0.6971	0.1763	0.4064	0.176*
H13B	−0.4254	0.1799	0.4891	0.176*
H13C	−0.6170	0.1795	0.5418	0.176*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0397 (2)	0.0421 (2)	0.0286 (2)	0.00210 (13)	0.00853 (15)	0.00111 (13)
O1	0.0710 (9)	0.0526 (7)	0.0297 (6)	0.0009 (6)	0.0187 (6)	0.0025 (5)
O2	0.0368 (6)	0.0628 (8)	0.0521 (8)	0.0056 (5)	0.0053 (5)	0.0070 (6)
O3	0.0668 (9)	0.0926 (11)	0.0443 (7)	0.0176 (8)	0.0288 (6)	0.0217 (7)
O4	0.0449 (7)	0.0863 (10)	0.0481 (7)	0.0147 (6)	0.0167 (6)	0.0204 (7)
N1	0.0342 (6)	0.0394 (6)	0.0305 (6)	0.0018 (5)	0.0136 (5)	0.0023 (5)
N2	0.0382 (6)	0.0502 (7)	0.0376 (6)	0.0057 (5)	0.0179 (5)	0.0107 (6)
C1	0.0568 (10)	0.0465 (9)	0.0550 (10)	−0.0022 (8)	0.0178 (8)	0.0017 (8)
C2	0.0690 (14)	0.0462 (11)	0.0853 (17)	−0.0098 (9)	0.0065 (12)	0.0024 (11)
C3	0.0979 (19)	0.0399 (10)	0.0691 (15)	0.0061 (11)	−0.0039 (13)	−0.0143 (10)
C4	0.1010 (19)	0.0625 (14)	0.0608 (13)	0.0193 (13)	0.0213 (13)	−0.0212 (11)
C5	0.0699 (12)	0.0580 (11)	0.0521 (10)	0.0106 (9)	0.0262 (9)	−0.0092 (9)
C6	0.0470 (8)	0.0366 (8)	0.0374 (7)	0.0065 (6)	0.0119 (6)	0.0000 (6)
C7	0.0366 (7)	0.0439 (8)	0.0364 (7)	0.0003 (6)	0.0192 (6)	0.0037 (6)
C8	0.0435 (7)	0.0449 (8)	0.0373 (7)	0.0074 (6)	0.0205 (6)	0.0040 (6)
C9	0.0376 (7)	0.0587 (10)	0.0494 (9)	0.0020 (7)	0.0220 (7)	0.0164 (8)
C10	0.0380 (7)	0.0556 (9)	0.0386 (8)	0.0075 (6)	0.0210 (6)	0.0076 (7)
C11	0.0455 (8)	0.0477 (9)	0.0375 (8)	0.0038 (6)	0.0169 (6)	0.0053 (6)
C12	0.0510 (10)	0.0811 (15)	0.0494 (10)	0.0032 (10)	0.0104 (8)	0.0043 (10)
C13	0.131 (3)	0.077 (2)	0.101 (2)	0.0254 (18)	0.003 (2)	0.0136 (17)

Geometric parameters (Å, º) top

S1—O1	1.4312 (13)	C4—H4A	0.9300
S1—O2	1.4320 (14)	C5—C6	1.389 (2)
S1—N1	1.6365 (13)	C5—H5A	0.9300
S1—C6	1.7634 (17)	C7—C8	1.518 (2)
O3—C11	1.210 (2)	C7—H7A	0.9700
O4—C11	1.346 (2)	C7—H7B	0.9700
O4—C12	1.465 (2)	C8—H8A	0.9700
N1—C10	1.4745 (18)	C8—H8B	0.9700
N1—C7	1.4755 (18)	C9—C10	1.518 (2)
N2—C11	1.347 (2)	C9—H9A	0.9700
N2—C8	1.4554 (19)	C9—H9B	0.9700
N2—C9	1.455 (2)	C10—H10A	0.9700
C1—C6	1.387 (3)	C10—H10B	0.9700
C1—C2	1.391 (3)	C12—C13	1.444 (4)
C1—H1A	0.9300	C12—H12A	0.9700
C2—C3	1.377 (4)	C12—H12C	0.9700
C2—H2A	0.9300	C13—H13A	0.9600
C3—C4	1.365 (4)	C13—H13B	0.9600
C3—H3A	0.9300	C13—H13C	0.9600
C4—C5	1.385 (3)

O1—S1—O2	119.62 (9)	C8—C7—H7B	109.9
O1—S1—N1	107.02 (7)	H7A—C7—H7B	108.3
O2—S1—N1	106.60 (7)	N2—C8—C7	110.26 (12)
O1—S1—C6	107.94 (8)	N2—C8—H8A	109.6
O2—S1—C6	108.04 (8)	C7—C8—H8A	109.6
N1—S1—C6	107.00 (7)	N2—C8—H8B	109.6
C11—O4—C12	115.91 (15)	C7—C8—H8B	109.6
C10—N1—C7	112.47 (11)	H8A—C8—H8B	108.1
C10—N1—S1	116.33 (10)	N2—C9—C10	109.69 (13)
C7—N1—S1	116.73 (10)	N2—C9—H9A	109.7
C11—N2—C8	126.01 (13)	C10—C9—H9A	109.7
C11—N2—C9	120.02 (13)	N2—C9—H9B	109.7
C8—N2—C9	113.96 (12)	C10—C9—H9B	109.7
C6—C1—C2	118.1 (2)	H9A—C9—H9B	108.2
C6—C1—H1A	121.0	N1—C10—C9	108.96 (13)
C2—C1—H1A	121.0	N1—C10—H10A	109.9
C3—C2—C1	120.9 (2)	C9—C10—H10A	109.9
C3—C2—H2A	119.6	N1—C10—H10B	109.9
C1—C2—H2A	119.6	C9—C10—H10B	109.9
C4—C3—C2	120.2 (2)	H10A—C10—H10B	108.3
C4—C3—H3A	119.9	O3—C11—O4	123.90 (15)
C2—C3—H3A	119.9	O3—C11—N2	124.31 (16)
C3—C4—C5	120.7 (2)	O4—C11—N2	111.78 (14)
C3—C4—H4A	119.6	C13—C12—O4	110.2 (2)
C5—C4—H4A	119.6	C13—C12—H12A	109.6
C4—C5—C6	118.7 (2)	O4—C12—H12A	109.6
C4—C5—H5A	120.7	C13—C12—H12C	109.6
C6—C5—H5A	120.7	O4—C12—H12C	109.6
C1—C6—C5	121.44 (18)	H12A—C12—H12C	108.1
C1—C6—S1	119.99 (14)	C12—C13—H13A	109.5
C5—C6—S1	118.55 (15)	C12—C13—H13B	109.5
N1—C7—C8	108.73 (12)	H13A—C13—H13B	109.5
N1—C7—H7A	109.9	C12—C13—H13C	109.5
C8—C7—H7A	109.9	H13A—C13—H13C	109.5
N1—C7—H7B	109.9	H13B—C13—H13C	109.5

O1—S1—N1—C10	175.82 (11)	N1—S1—C6—C5	85.65 (15)
O2—S1—N1—C10	46.71 (13)	C10—N1—C7—C8	−58.52 (17)
C6—S1—N1—C10	−68.69 (13)	S1—N1—C7—C8	163.26 (10)
O1—S1—N1—C7	−47.57 (12)	C11—N2—C8—C7	122.68 (18)
O2—S1—N1—C7	−176.67 (11)	C9—N2—C8—C7	−56.43 (18)
C6—S1—N1—C7	67.92 (12)	N1—C7—C8—N2	55.05 (16)
C6—C1—C2—C3	−0.5 (3)	C11—N2—C9—C10	−122.59 (17)
C1—C2—C3—C4	0.2 (4)	C8—N2—C9—C10	56.58 (19)
C2—C3—C4—C5	0.0 (4)	C7—N1—C10—C9	59.10 (17)
C3—C4—C5—C6	0.0 (3)	S1—N1—C10—C9	−162.49 (11)
C2—C1—C6—C5	0.5 (3)	N2—C9—C10—N1	−55.79 (18)
C2—C1—C6—S1	179.12 (15)	C12—O4—C11—O3	2.6 (3)
C4—C5—C6—C1	−0.3 (3)	C12—O4—C11—N2	−176.51 (17)
C4—C5—C6—S1	−178.91 (16)	C8—N2—C11—O3	178.53 (18)
O1—S1—C6—C1	21.89 (16)	C9—N2—C11—O3	−2.4 (3)
O2—S1—C6—C1	152.57 (14)	C8—N2—C11—O4	−2.4 (2)
N1—S1—C6—C1	−92.99 (15)	C9—N2—C11—O4	176.66 (15)
O1—S1—C6—C5	−159.47 (14)	C11—O4—C12—C13	−88.6 (3)
O2—S1—C6—C5	−28.79 (17)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···Cg1ⁱ	0.96	2.97	3.900 (4)	165

Symmetry code: (i) −x−1, −y, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₈N₂O₄S
M_r	298.35
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	6.1433 (5), 20.5966 (17), 12.5626 (8)
β (°)	114.026 (3)
V (Å³)	1451.84 (19)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.58 × 0.38 × 0.17

Data collection
Diffractometer	Bruker APEXII DUO CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.875, 0.961
No. of measured, independent and observed [I > 2σ(I)] reflections	16507, 4255, 3400
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.706

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.158, 1.04
No. of reflections	4255
No. of parameters	182
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.60, −0.30

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13A···Cg1ⁱ	0.96	2.97	3.900 (4)	165

Symmetry code: (i) −x−1, −y, −z+1.

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

NM gratefully acknowledges funding from the Malaysian Ministry of Science, Technology and Innovation, through the Malaysian Institute of Pharmaceutical and Nutraceutical R&D Initiative Grant (grant No. 09-05-IFN-MEB 004 and 304/PFARMASI/650512/I121). HKF and MH thank the Malaysian Government and Universiti Sains Malaysia for the Research University Grant No. 1001/PFIZIK/811160. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

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