A second monoclinic polymorph of N-cyclo­hexyl-N-ethyl­benzene­sulfonamide

Haider, Z.; Arshad, M.N.; Zia-ur-Rehman, M.; Khan, I.U.; Shafiq, M.

doi:10.1107/S160053680904762X

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page o3107

doi:10.1107/S160053680904762X

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A second monoclinic polymorph of N-cyclohexyl-N-ethylbenzenesulfonamide

Zeeshan Haider,^a Muhammad Nadeem Arshad,^a Muhammad Zia-ur-Rehman,^b Islam Ullah Khan ^a ^* and Muhammad Shafiq ^a

^aDepartment of Chemistry, Government College University, Lahore 54000, Pakistan, and ^bApplied Chemistry Research Centre, PCSIR Laboratories Complex, Ferozpure Road, Lahore 54600, Pakistan
^*Correspondence e-mail: iukhan.gcu@gmail.com

(Received 9 November 2009; accepted 10 November 2009; online 18 November 2009)

The crystal structure of the title compound, C₁₄H₂₁NO₂S, is a polymorph of the structure reported by Khan et al. [Acta Cryst. (2009), E65, o2867] which is also monoclinic (space group P2₁/c). The unit cell in the title structure is approximately half the volume of the previously reported polymorph and the asymmetric unit of the title compound contains one molecule rather than two independent molecules in the other polymorph. In the title molecule, the cyclohexane ring is in the typical chair form. In the crystal structure, molecules are linked via weak intermolecular C—H⋯O interactions, forming a chain along the b-axis direction.

Related literature

For the synthesis of related molecules, see: Arshad et al. (2009 ); Zia-ur-Rehman et al. (2009 ). For applications of sulfonamides, see: Connor (1998 ); Berredjem et al. (2000 ); Lee & Lee (2002 ); Xiao & Timberlake (2000 ). For the structure of the other polymorph, see: Khan et al. (2009 ). For standard bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₄H₂₁NO₂S
M_r = 267.38
Monoclinic, P 2₁ /n
a = 8.3837 (4) Å
b = 11.4467 (5) Å
c = 15.1488 (7) Å
β = 92.541 (2)°
V = 1452.34 (12) Å³
Z = 4
Mo Kα radiation
μ = 0.22 mm⁻¹
T = 296 K
0.41 × 0.28 × 0.11 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ) T_min = 0.916, T_max = 0.976
15910 measured reflections
3651 independent reflections
2481 reflections with I > 2σ(I)
R_int = 0.034

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.107
S = 1.02
3651 reflections
164 parameters
H-atom parameters constrained
Δρ_max = 0.26 e Å⁻³
Δρ_min = −0.36 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O2ⁱ	0.93	2.58	3.482 (2)	163
Symmetry code: (i) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: WinGX (Farrugia,1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680904762X/lh2950sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680904762X/lh2950Isup2.hkl

checkCIF report

Comment top

Sulfonamides are an important category of pharmaceutical compounds with a broad spectrum of biological activities such as herbicidal, anti-malarial, anti-convulsant and anti-hypertensive (Connor, 1998; Xiao & Timberlake, 2000; Berredjem et al., 2000; Lee & Lee, 2002).

As a part of our ongoing research program regarding the synthesis of sulfur containing heterocyclic compounds (Arshad et al., 2009; Zia-ur-Rehman et al. 2009), we, herein report the crystal structure of the title compound as a new polymorph of the structure previously reported by Khan et al. (2009) which is also monoclinic (space group P2₁/c), but with completely different unit cell constants. The molecular structure of the title compound (I) is shown in Fig. 1. The asymmetric unit contains single molecule instead of two as observed in the previous form. In the molecule of (I), bond lengths (Allen et al., 1987) and bond angles are within the normal ranges. The cyclohexane ring is in the chair form. In the crystal structure, molecule are linked via weak intermolecular C—H···O hydrogen bonds to form chains along the b axis direction.

Related literature top

For the synthesis of related molecules, see: Arshad et al. (2009); Zia-ur-Rehman et al. (2009). For applications of sulfonamides, see: Connor (1998); Berredjem et al. (2000); Lee & Lee (2002); Xiao & Timberlake (2000). For the structure of the other polymorph, see: Khan et al. (2009). For standard bond-length data, see: Allen et al. (1987).

Experimental top

A mixture of N-cyclohexylbenzene sulfonamide (1.0 g, 0.43 mmol), sodium hydride (0.21 g; 0.88 mmoles) and N, N-dimethylformamide (10.0 ml) was stirred at room temperature for half an hour followed by addition of ethyl iodide (0.134 g; 0.86 mmoles). Stirring was continued further for a period of three hours and the contents were poured over crushed ice. Precipitated product was isolated, washed and crystallized from methanol.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia,1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I), with displacement ellipsoids at the 50% probability level.
	Fig. 2. Part of the crystal structure showing weak C-H···O hydrogen bonds as dashed lines. H atoms not involved in hydrogen bonding have been omitted for clarity.

N-cyclohexyl-N-ethylbenzenesulfonamide top

Crystal data top

C₁₄H₂₁NO₂S	F(000) = 576
M_r = 267.38	D_x = 1.223 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4610 reflections
a = 8.3837 (4) Å	θ = 2.8–27.6°
b = 11.4467 (5) Å	µ = 0.22 mm⁻¹
c = 15.1488 (7) Å	T = 296 K
β = 92.541 (2)°	Needle, colourless
V = 1452.34 (12) Å³	0.41 × 0.28 × 0.11 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	3651 independent reflections
Radiation source: fine-focus sealed tube	2481 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ϕ and ω scans	θ_max = 28.5°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	h = −11→10
T_min = 0.916, T_max = 0.976	k = −15→14
15910 measured reflections	l = −19→20

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.107	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0409P)² + 0.3342P] where P = (F_o² + 2F_c²)/3
3651 reflections	(Δ/σ)_max = 0.001
164 parameters	Δρ_max = 0.26 e Å⁻³
0 restraints	Δρ_min = −0.36 e Å⁻³

Crystal data top

C₁₄H₂₁NO₂S	V = 1452.34 (12) Å³
M_r = 267.38	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.3837 (4) Å	µ = 0.22 mm⁻¹
b = 11.4467 (5) Å	T = 296 K
c = 15.1488 (7) Å	0.41 × 0.28 × 0.11 mm
β = 92.541 (2)°

Data collection top

Bruker APEXII CCD diffractometer	3651 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	2481 reflections with I > 2σ(I)
T_min = 0.916, T_max = 0.976	R_int = 0.034
15910 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.107	H-atom parameters constrained
S = 1.02	Δρ_max = 0.26 e Å⁻³
3651 reflections	Δρ_min = −0.36 e Å⁻³
164 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
S1	0.22296 (5)	0.78592 (4)	0.73395 (3)	0.04988 (15)
O1	0.14310 (16)	0.68075 (13)	0.70635 (9)	0.0702 (4)
O2	0.14198 (15)	0.89484 (12)	0.72376 (10)	0.0720 (4)
N1	0.38527 (16)	0.79318 (12)	0.68134 (9)	0.0455 (3)
C1	0.27998 (18)	0.77256 (14)	0.84693 (10)	0.0427 (4)
C2	0.2929 (3)	0.87099 (18)	0.89914 (13)	0.0658 (5)
H2	0.2641	0.9436	0.8760	0.079*
C3	0.3483 (3)	0.8612 (2)	0.98515 (15)	0.0841 (7)
H3	0.3569	0.9276	1.0205	0.101*
C4	0.3908 (3)	0.7554 (3)	1.01939 (14)	0.0809 (7)
H4	0.4296	0.7497	1.0777	0.097*
C5	0.3767 (2)	0.6566 (2)	0.96771 (14)	0.0710 (6)
H5	0.4048	0.5843	0.9916	0.085*
C6	0.3209 (2)	0.66398 (16)	0.88051 (12)	0.0528 (4)
H6	0.3113	0.5975	0.8454	0.063*
C7	0.49240 (18)	0.89465 (14)	0.69898 (10)	0.0410 (4)
H7	0.4309	0.9530	0.7304	0.049*
C8	0.6390 (2)	0.86509 (15)	0.75812 (11)	0.0507 (4)
H8A	0.6055	0.8330	0.8136	0.061*
H8B	0.7026	0.8065	0.7296	0.061*
C9	0.7397 (2)	0.97408 (17)	0.77604 (11)	0.0579 (5)
H9A	0.6786	1.0303	0.8085	0.069*
H9B	0.8340	0.9536	0.8121	0.069*
C10	0.7892 (2)	1.02824 (16)	0.69050 (12)	0.0547 (5)
H10A	0.8578	0.9744	0.6605	0.066*
H10B	0.8495	1.0990	0.7033	0.066*
C11	0.6449 (2)	1.05710 (15)	0.63070 (12)	0.0550 (4)
H11A	0.6803	1.0871	0.5750	0.066*
H11B	0.5828	1.1177	0.6580	0.066*
C12	0.53986 (19)	0.95047 (14)	0.61323 (10)	0.0457 (4)
H12A	0.4446	0.9735	0.5789	0.055*
H12B	0.5971	0.8939	0.5790	0.055*
C13	0.4471 (2)	0.68754 (15)	0.63861 (12)	0.0542 (5)
H13A	0.4181	0.6195	0.6726	0.065*
H13B	0.5627	0.6916	0.6396	0.065*
C14	0.3849 (3)	0.67214 (18)	0.54449 (13)	0.0760 (6)
H14A	0.2704	0.6677	0.5429	0.114*
H14B	0.4273	0.6014	0.5208	0.114*
H14C	0.4172	0.7374	0.5098	0.114*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0385 (2)	0.0606 (3)	0.0500 (3)	−0.0046 (2)	−0.00434 (17)	0.0147 (2)
O1	0.0615 (8)	0.0877 (10)	0.0603 (8)	−0.0332 (7)	−0.0110 (6)	0.0087 (7)
O2	0.0469 (7)	0.0815 (10)	0.0880 (10)	0.0182 (7)	0.0050 (7)	0.0353 (8)
N1	0.0459 (8)	0.0483 (8)	0.0421 (7)	−0.0072 (6)	0.0015 (6)	0.0003 (6)
C1	0.0378 (8)	0.0476 (9)	0.0431 (9)	−0.0015 (7)	0.0050 (7)	0.0043 (7)
C2	0.0839 (14)	0.0548 (12)	0.0599 (12)	0.0012 (10)	0.0160 (10)	−0.0002 (9)
C3	0.1083 (19)	0.0908 (18)	0.0541 (13)	−0.0248 (15)	0.0138 (12)	−0.0155 (12)
C4	0.0689 (14)	0.131 (2)	0.0427 (11)	−0.0152 (14)	−0.0031 (10)	0.0049 (13)
C5	0.0665 (13)	0.0872 (16)	0.0594 (12)	0.0133 (12)	0.0045 (10)	0.0285 (12)
C6	0.0543 (10)	0.0529 (11)	0.0513 (10)	0.0005 (9)	0.0064 (8)	0.0090 (8)
C7	0.0408 (8)	0.0433 (9)	0.0387 (8)	−0.0020 (7)	0.0010 (6)	0.0009 (7)
C8	0.0509 (10)	0.0581 (11)	0.0422 (9)	−0.0051 (8)	−0.0066 (7)	0.0079 (8)
C9	0.0556 (11)	0.0678 (13)	0.0494 (10)	−0.0100 (9)	−0.0087 (8)	−0.0030 (9)
C10	0.0516 (10)	0.0528 (11)	0.0599 (11)	−0.0123 (8)	0.0033 (8)	−0.0052 (8)
C11	0.0592 (11)	0.0480 (10)	0.0580 (11)	−0.0046 (8)	0.0052 (9)	0.0101 (8)
C12	0.0456 (9)	0.0512 (10)	0.0399 (9)	−0.0009 (8)	−0.0014 (7)	0.0087 (7)
C13	0.0606 (11)	0.0449 (10)	0.0567 (11)	−0.0022 (8)	−0.0024 (9)	0.0017 (8)
C14	0.1067 (18)	0.0615 (13)	0.0591 (12)	−0.0003 (12)	−0.0042 (12)	−0.0115 (10)

Geometric parameters (Å, º) top

S1—O2	1.4247 (13)	C8—C9	1.524 (2)
S1—O1	1.4309 (14)	C8—H8A	0.9700
S1—N1	1.6093 (14)	C8—H8B	0.9700
S1—C1	1.7632 (16)	C9—C10	1.511 (2)
N1—C13	1.476 (2)	C9—H9A	0.9700
N1—C7	1.485 (2)	C9—H9B	0.9700
C1—C2	1.378 (2)	C10—C11	1.515 (2)
C1—C6	1.381 (2)	C10—H10A	0.9700
C2—C3	1.368 (3)	C10—H10B	0.9700
C2—H2	0.9300	C11—C12	1.521 (2)
C3—C4	1.359 (3)	C11—H11A	0.9700
C3—H3	0.9300	C11—H11B	0.9700
C4—C5	1.377 (3)	C12—H12A	0.9700
C4—H4	0.9300	C12—H12B	0.9700
C5—C6	1.384 (3)	C13—C14	1.507 (3)
C5—H5	0.9300	C13—H13A	0.9700
C6—H6	0.9300	C13—H13B	0.9700
C7—C12	1.516 (2)	C14—H14A	0.9600
C7—C8	1.527 (2)	C14—H14B	0.9600
C7—H7	0.9800	C14—H14C	0.9600

O2—S1—O1	119.34 (9)	H8A—C8—H8B	108.1
O2—S1—N1	108.08 (8)	C10—C9—C8	110.74 (14)
O1—S1—N1	107.08 (8)	C10—C9—H9A	109.5
O2—S1—C1	106.77 (9)	C8—C9—H9A	109.5
O1—S1—C1	108.29 (8)	C10—C9—H9B	109.5
N1—S1—C1	106.64 (7)	C8—C9—H9B	109.5
C13—N1—C7	119.89 (13)	H9A—C9—H9B	108.1
C13—N1—S1	119.71 (11)	C9—C10—C11	111.09 (15)
C7—N1—S1	117.98 (11)	C9—C10—H10A	109.4
C2—C1—C6	120.85 (16)	C11—C10—H10A	109.4
C2—C1—S1	119.81 (14)	C9—C10—H10B	109.4
C6—C1—S1	119.21 (13)	C11—C10—H10B	109.4
C3—C2—C1	119.6 (2)	H10A—C10—H10B	108.0
C3—C2—H2	120.2	C10—C11—C12	111.69 (14)
C1—C2—H2	120.2	C10—C11—H11A	109.3
C4—C3—C2	120.6 (2)	C12—C11—H11A	109.3
C4—C3—H3	119.7	C10—C11—H11B	109.3
C2—C3—H3	119.7	C12—C11—H11B	109.3
C3—C4—C5	120.01 (19)	H11A—C11—H11B	107.9
C3—C4—H4	120.0	C7—C12—C11	111.15 (13)
C5—C4—H4	120.0	C7—C12—H12A	109.4
C4—C5—C6	120.6 (2)	C11—C12—H12A	109.4
C4—C5—H5	119.7	C7—C12—H12B	109.4
C6—C5—H5	119.7	C11—C12—H12B	109.4
C1—C6—C5	118.32 (18)	H12A—C12—H12B	108.0
C1—C6—H6	120.8	N1—C13—C14	113.41 (15)
C5—C6—H6	120.8	N1—C13—H13A	108.9
N1—C7—C12	110.79 (12)	C14—C13—H13A	108.9
N1—C7—C8	113.40 (13)	N1—C13—H13B	108.9
C12—C7—C8	111.16 (13)	C14—C13—H13B	108.9
N1—C7—H7	107.0	H13A—C13—H13B	107.7
C12—C7—H7	107.0	C13—C14—H14A	109.5
C8—C7—H7	107.0	C13—C14—H14B	109.5
C9—C8—C7	110.38 (14)	H14A—C14—H14B	109.5
C9—C8—H8A	109.6	C13—C14—H14C	109.5
C7—C8—H8A	109.6	H14A—C14—H14C	109.5
C9—C8—H8B	109.6	H14B—C14—H14C	109.5
C7—C8—H8B	109.6

O2—S1—N1—C13	−146.72 (13)	C2—C1—C6—C5	−0.6 (3)
O1—S1—N1—C13	−16.96 (14)	S1—C1—C6—C5	175.29 (14)
C1—S1—N1—C13	98.80 (13)	C4—C5—C6—C1	−0.1 (3)
O2—S1—N1—C7	50.94 (13)	C13—N1—C7—C12	66.92 (17)
O1—S1—N1—C7	−179.30 (11)	S1—N1—C7—C12	−130.77 (12)
C1—S1—N1—C7	−63.54 (13)	C13—N1—C7—C8	−58.89 (19)
O2—S1—C1—C2	−21.71 (17)	S1—N1—C7—C8	103.43 (15)
O1—S1—C1—C2	−151.40 (15)	N1—C7—C8—C9	−177.88 (13)
N1—S1—C1—C2	93.66 (16)	C12—C7—C8—C9	56.52 (19)
O2—S1—C1—C6	162.38 (13)	C7—C8—C9—C10	−57.4 (2)
O1—S1—C1—C6	32.69 (16)	C8—C9—C10—C11	56.9 (2)
N1—S1—C1—C6	−82.25 (15)	C9—C10—C11—C12	−55.4 (2)
C6—C1—C2—C3	0.6 (3)	N1—C7—C12—C11	178.00 (13)
S1—C1—C2—C3	−175.27 (16)	C8—C7—C12—C11	−54.96 (19)
C1—C2—C3—C4	0.1 (3)	C10—C11—C12—C7	54.4 (2)
C2—C3—C4—C5	−0.7 (4)	C7—N1—C13—C14	−107.93 (18)
C3—C4—C5—C6	0.7 (3)	S1—N1—C13—C14	90.06 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2ⁱ	0.93	2.58	3.482 (2)	163

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

Experimental details

Crystal data
Chemical formula	C₁₄H₂₁NO₂S
M_r	267.38
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	8.3837 (4), 11.4467 (5), 15.1488 (7)
β (°)	92.541 (2)
V (Å³)	1452.34 (12)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.22
Crystal size (mm)	0.41 × 0.28 × 0.11

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2007)
T_min, T_max	0.916, 0.976
No. of measured, independent and observed [I > 2σ(I)] reflections	15910, 3651, 2481
R_int	0.034
(sin θ/λ)_max (Å⁻¹)	0.671

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.107, 1.02
No. of reflections	3651
No. of parameters	164
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.26, −0.36

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and Mercury (Macrae et al., 2006), WinGX (Farrugia,1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O2ⁱ	0.9300	2.5800	3.482 (2)	163.00

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

Acknowledgements

The authors are grateful to the Higher Education Commission of Pakistan for financial support to purchase the diffractometer.

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