An ortho­rhom­bic polymorph of 2-(1,3-benzothia­zol-2-yl)-6-eth­oxy­phenol

Kargar, H.; Kia, R.; Sharafi, Z.; Jahromi, H.J.; Tahir, M.N.

doi:10.1107/S1600536812033879

organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2628

doi:10.1107/S1600536812033879

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An orthorhombic polymorph of 2-(1,3-benzothiazol-2-yl)-6-ethoxyphenol

Hadi Kargar,^a Reza Kia,^b,^c ^* Zahra Sharafi,^d Hossein Jalali Jahromi ^e and Muhammad Nawaz Tahir ^f ^*

^aDepartment of Chemistry, Payame Noor University, PO Box 19395-3697 Tehran, I. R. of IRAN, ^bDepartment of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, Iran, ^cStructural Dynamics of (Bio)Chemical Systems, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany, ^dDepartment of Chemistry, Marvdasht Branch, Islamic Azad University, Marvdasht, Iran, ^eDepartment of Chemistry and Chemical Engineering, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran, and ^fDepartment of Physics, University of Sargodha, Punjab, Pakistan
^*Correspondence e-mail: zsrkk@yahoo.com, dmntahir_uos@yahoo.com

(Received 22 July 2012; accepted 28 July 2012; online 4 August 2012)

In the title molecule, C₁₅H₁₃NO₂S, an intramolecular O—H⋯N hydrogen bond forms an S(6) ring motif. The benzothiazole ring system and the benzene ring form a dihedral angle of 8.9 (3) Å. In the crystal, molecules are linked by weak C—H⋯O hydrogen bonds, forming chains along the b axis. In addition, π–π interactions [centroid–centroid distances = 3.772 (4) and 3.879 (4) Å] are observed.

Related literature

For the monoclinic polymorph, see: Lakshmanan et al. (2011 ). For background to and examples of the structures of Schiff base ligands see: Kargar et al. (2011 ); Kia et al. (2010 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ). For standard bond lengths, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₅H₁₃NO₂S
M_r = 271.32
Orthorhombic, P 2₁ 2₁ 2₁
a = 4.8728 (10) Å
b = 11.711 (3) Å
c = 23.378 (6) Å
V = 1334.1 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 296 K
0.33 × 0.23 × 0.21 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.925, T_max = 0.952
4083 measured reflections
2239 independent reflections
1207 reflections with I > 2σ(I)
R_int = 0.073

Refinement

R[F² > 2σ(F²)] = 0.068
wR(F²) = 0.144
S = 0.99
2239 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.30 e Å⁻³
Absolute structure: Flack (1983 ), 874 Friedel pairs
Flack parameter: −0.1 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.88	1.76	2.592 (6)	158
C2—H2⋯O1ⁱ	0.93	2.55	3.372 (8)	148
Symmetry code: (i) $[-x+2, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); 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/S1600536812033879/lh5505sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812033879/lh5505Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812033879/lh5505Isup3.cml

checkCIF report

Comment top

In continuation of our work on the crystal structures of Schiff base ligands from different substituted salicylaldehyde and amines (Kargar et al., 2011; Kia et al., 2010), we have determined the X-ray structure of the title compound. The crystal structure of a monoclinic polymorph of the title compound has already been published (Lakshmanan et al., 2011).

The molecular structure of the title compound is shown in Fig. 1. The bond lengths (Allen et al., 1987) and angles are within the normal ranges. An intramolecular O—H···N hydrogen bond forms a S(6) ring motif (Bernstein et al., 1995). In the crystal, molecules are linked by weak intermolecular C—H···O hydrogen bonds forming one-dimensional chains along the b axis (Table 2, Fig. 2). In addition, weak intermolecular π–π interactions are observed [Cg1···Cg2ⁱⁱ = 3.772 (4) Å, (ii) -1 + x, y, z; Cg1···Cg3ⁱⁱⁱ = 3.879 (4), (iii) 1 + x, y, z, Cg1, Cg2 and Cg3 are centroid of S1/C1/C6/N1/C7, C1–C6, and C8–C13 rings].

Related literature top

For the monoclinic polymorph, see: Lakshmanan et al. (2011). For background to and examples of the structures of Schiff base ligands see: Kargar et al. (2011); Kia et al. (2010). For hydrogen-bond motifs, see: Bernstein et al. (1995). For standard bond lengths, see: Allen et al. (1987).

Experimental top

The title compound was synthesized by adding 3-ethoxysalicylaldehyde (2 mmol) to a solution of 2-aminothiophenol (2mmol) in ethanol (30 ml). The mixture was refluxed with stirring for half an hour. The resultant solution was filtered. Light-yellow prismatic single crystals of the title compound suitable for X-ray structure determination were recrystallized from ethanol by slow evaporation of the solvent at room temperature over several days.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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 the title compound, showing 40% probability displacement ellipsoids. The dashed line indicates an intramolecular hydrogen bond.
	Fig. 2. Part of the crystal structure with weak hydrogen bonds shown as dashed lines.

2-(1,3-Benzothiazol-2-yl)-6-ethoxyphenol top

Crystal data top

C₁₅H₁₃NO₂S	F(000) = 568
M_r = 271.32	D_x = 1.351 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 864 reflections
a = 4.8728 (10) Å	θ = 2.5–28.8°
b = 11.711 (3) Å	µ = 0.24 mm⁻¹
c = 23.378 (6) Å	T = 296 K
V = 1334.1 (6) Å³	Prism, light-yellow
Z = 4	0.33 × 0.23 × 0.21 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	2239 independent reflections
Radiation source: fine-focus sealed tube	1207 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.073
ω scans	θ_max = 25.0°, θ_min = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −3→5
T_min = 0.925, T_max = 0.952	k = −9→13
4083 measured reflections	l = −27→19

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.068	H-atom parameters constrained
wR(F²) = 0.144	w = 1/[σ²(F_o²) + (0.0413P)²] where P = (F_o² + 2F_c²)/3
S = 0.99	(Δ/σ)_max < 0.001
2239 reflections	Δρ_max = 0.19 e Å⁻³
173 parameters	Δρ_min = −0.30 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 874 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.1 (2)

Crystal data top

C₁₅H₁₃NO₂S	V = 1334.1 (6) Å³
M_r = 271.32	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 4.8728 (10) Å	µ = 0.24 mm⁻¹
b = 11.711 (3) Å	T = 296 K
c = 23.378 (6) Å	0.33 × 0.23 × 0.21 mm

Data collection top

Bruker SMART APEXII CCD diffractometer	2239 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	1207 reflections with I > 2σ(I)
T_min = 0.925, T_max = 0.952	R_int = 0.073
4083 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.068	H-atom parameters constrained
wR(F²) = 0.144	Δρ_max = 0.19 e Å⁻³
S = 0.99	Δρ_min = −0.30 e Å⁻³
2239 reflections	Absolute structure: Flack (1983), 874 Friedel pairs
173 parameters	Absolute structure parameter: −0.1 (2)
0 restraints

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

	x	y	z	U_iso*/U_eq
C1	1.2770 (11)	0.2177 (4)	0.2096 (3)	0.0485 (16)
C2	1.4128 (13)	0.1882 (5)	0.1606 (3)	0.0647 (19)
H2	1.3725	0.1196	0.1423	0.078*
C3	1.6064 (14)	0.2590 (6)	0.1386 (3)	0.073 (2)
H3	1.6970	0.2397	0.1049	0.087*
C4	1.6692 (13)	0.3614 (6)	0.1667 (3)	0.0670 (18)
H4	1.8030	0.4093	0.1516	0.080*
C5	1.5378 (14)	0.3923 (5)	0.2160 (3)	0.0599 (17)
H5	1.5816	0.4606	0.2342	0.072*
C6	1.3392 (11)	0.3211 (5)	0.2386 (3)	0.0458 (15)
N1	1.1883 (9)	0.3431 (4)	0.2872 (2)	0.0468 (12)
C8	0.8322 (12)	0.2602 (5)	0.3462 (3)	0.0509 (16)
C9	0.8043 (12)	0.3576 (5)	0.3797 (3)	0.0530 (16)
C10	0.6091 (12)	0.3608 (6)	0.4232 (3)	0.0603 (17)
C11	0.4481 (14)	0.2664 (6)	0.4350 (3)	0.0664 (19)
H11	0.3218	0.2685	0.4648	0.080*
C12	0.4756 (15)	0.1698 (6)	0.4026 (3)	0.0686 (18)
H12	0.3661	0.1067	0.4105	0.082*
C13	0.6598 (12)	0.1642 (5)	0.3590 (3)	0.0568 (16)
H13	0.6740	0.0979	0.3373	0.068*
C14	0.3939 (15)	0.4754 (6)	0.4949 (3)	0.084 (2)
H14A	0.4162	0.4185	0.5246	0.101*
H14B	0.2133	0.4663	0.4780	0.101*
C15	0.4237 (18)	0.5927 (7)	0.5194 (3)	0.118 (3)
H15A	0.6144	0.6088	0.5257	0.176*
H15B	0.3265	0.5970	0.5551	0.176*
H15C	0.3492	0.6476	0.4932	0.176*
C7	1.0189 (12)	0.2585 (4)	0.2991 (2)	0.0472 (15)
O1	0.9557 (8)	0.4529 (3)	0.37058 (16)	0.0633 (12)
H1	1.0595	0.4317	0.3417	0.095*
O2	0.5994 (9)	0.4617 (4)	0.45248 (18)	0.0741 (13)
S1	1.0285 (3)	0.14638 (12)	0.24914 (8)	0.0574 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.039 (4)	0.049 (4)	0.057 (4)	0.007 (3)	−0.008 (3)	0.004 (3)
C2	0.064 (5)	0.063 (4)	0.067 (5)	0.008 (4)	−0.006 (4)	−0.003 (4)
C3	0.065 (5)	0.088 (6)	0.064 (5)	0.004 (4)	0.007 (4)	0.009 (5)
C4	0.064 (4)	0.063 (5)	0.074 (5)	−0.013 (4)	−0.008 (4)	0.019 (4)
C5	0.066 (5)	0.048 (4)	0.066 (4)	−0.001 (4)	−0.012 (4)	0.003 (4)
C6	0.038 (3)	0.036 (3)	0.063 (5)	0.005 (3)	−0.005 (3)	0.009 (3)
N1	0.040 (3)	0.036 (3)	0.064 (3)	−0.001 (3)	−0.010 (3)	0.001 (3)
C8	0.043 (4)	0.045 (4)	0.065 (4)	0.001 (3)	−0.010 (3)	0.008 (4)
C9	0.043 (4)	0.049 (4)	0.067 (5)	0.005 (3)	−0.006 (3)	0.018 (4)
C10	0.055 (4)	0.066 (4)	0.060 (4)	0.005 (4)	−0.006 (3)	−0.001 (4)
C11	0.055 (5)	0.076 (5)	0.068 (5)	−0.005 (4)	0.002 (4)	0.010 (4)
C12	0.063 (4)	0.065 (5)	0.078 (5)	−0.011 (4)	−0.004 (4)	0.019 (4)
C13	0.057 (4)	0.041 (4)	0.072 (5)	−0.006 (4)	−0.008 (4)	0.008 (4)
C14	0.083 (6)	0.105 (6)	0.063 (5)	0.004 (5)	0.014 (4)	−0.007 (5)
C15	0.142 (8)	0.116 (7)	0.095 (6)	0.016 (6)	0.027 (6)	−0.035 (5)
C7	0.046 (4)	0.038 (3)	0.057 (4)	0.008 (3)	−0.015 (3)	0.000 (3)
O1	0.066 (3)	0.045 (2)	0.078 (3)	0.000 (2)	0.011 (2)	−0.004 (2)
O2	0.073 (3)	0.077 (3)	0.072 (3)	−0.004 (3)	0.015 (3)	−0.007 (3)
S1	0.0528 (9)	0.0410 (7)	0.0784 (11)	−0.0014 (8)	−0.0047 (10)	−0.0030 (10)

Geometric parameters (Å, º) top

C1—C2	1.368 (8)	C9—C10	1.393 (7)
C1—C6	1.421 (7)	C10—O2	1.366 (7)
C1—S1	1.737 (6)	C10—C11	1.384 (8)
C2—C3	1.358 (8)	C11—C12	1.368 (8)
C2—H2	0.9300	C11—H11	0.9300
C3—C4	1.402 (8)	C12—C13	1.360 (8)
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.368 (8)	C13—H13	0.9300
C4—H4	0.9300	C14—O2	1.418 (7)
C5—C6	1.382 (7)	C14—C15	1.496 (9)
C5—H5	0.9300	C14—H14A	0.9700
C6—N1	1.377 (7)	C14—H14B	0.9700
N1—C7	1.318 (6)	C15—H15A	0.9600
C8—C9	1.391 (8)	C15—H15B	0.9600
C8—C7	1.428 (7)	C15—H15C	0.9600
C8—C13	1.435 (8)	C7—S1	1.758 (5)
C9—O1	1.355 (6)	O1—H1	0.8797

C2—C1—C6	120.8 (6)	C12—C11—C10	119.7 (6)
C2—C1—S1	131.4 (5)	C12—C11—H11	120.2
C6—C1—S1	107.7 (4)	C10—C11—H11	120.2
C3—C2—C1	120.0 (6)	C13—C12—C11	121.3 (6)
C3—C2—H2	120.0	C13—C12—H12	119.3
C1—C2—H2	120.0	C11—C12—H12	119.3
C2—C3—C4	119.7 (6)	C12—C13—C8	120.3 (6)
C2—C3—H3	120.1	C12—C13—H13	119.8
C4—C3—H3	120.1	C8—C13—H13	119.8
C5—C4—C3	121.4 (6)	O2—C14—C15	107.7 (6)
C5—C4—H4	119.3	O2—C14—H14A	110.2
C3—C4—H4	119.3	C15—C14—H14A	110.2
C4—C5—C6	119.4 (6)	O2—C14—H14B	110.2
C4—C5—H5	120.3	C15—C14—H14B	110.2
C6—C5—H5	120.3	H14A—C14—H14B	108.5
N1—C6—C5	125.2 (6)	C14—C15—H15A	109.5
N1—C6—C1	116.0 (5)	C14—C15—H15B	109.5
C5—C6—C1	118.7 (5)	H15A—C15—H15B	109.5
C7—N1—C6	111.6 (5)	C14—C15—H15C	109.5
C9—C8—C7	120.5 (5)	H15A—C15—H15C	109.5
C9—C8—C13	117.9 (6)	H15B—C15—H15C	109.5
C7—C8—C13	121.5 (6)	N1—C7—C8	123.4 (5)
O1—C9—C8	122.2 (5)	N1—C7—S1	113.9 (4)
O1—C9—C10	117.7 (6)	C8—C7—S1	122.6 (5)
C8—C9—C10	120.0 (6)	C9—O1—H1	101.7
O2—C10—C11	124.9 (6)	C10—O2—C14	118.2 (5)
O2—C10—C9	114.3 (6)	C1—S1—C7	90.7 (3)
C11—C10—C9	120.7 (6)

C6—C1—C2—C3	−1.2 (8)	C8—C9—C10—C11	2.3 (9)
S1—C1—C2—C3	−178.3 (5)	O2—C10—C11—C12	179.8 (6)
C1—C2—C3—C4	1.0 (9)	C9—C10—C11—C12	−1.8 (9)
C2—C3—C4—C5	−0.5 (10)	C10—C11—C12—C13	0.4 (10)
C3—C4—C5—C6	0.1 (9)	C11—C12—C13—C8	0.5 (10)
C4—C5—C6—N1	−178.7 (5)	C9—C8—C13—C12	0.1 (9)
C4—C5—C6—C1	−0.3 (8)	C7—C8—C13—C12	−177.2 (6)
C2—C1—C6—N1	179.4 (5)	C6—N1—C7—C8	−178.1 (5)
S1—C1—C6—N1	−2.9 (6)	C6—N1—C7—S1	−1.6 (6)
C2—C1—C6—C5	0.8 (8)	C9—C8—C7—N1	5.5 (8)
S1—C1—C6—C5	178.6 (4)	C13—C8—C7—N1	−177.3 (5)
C5—C6—N1—C7	−178.6 (5)	C9—C8—C7—S1	−170.7 (4)
C1—C6—N1—C7	3.0 (6)	C13—C8—C7—S1	6.6 (8)
C7—C8—C9—O1	−1.9 (8)	C11—C10—O2—C14	−5.8 (9)
C13—C8—C9—O1	−179.3 (5)	C9—C10—O2—C14	175.7 (5)
C7—C8—C9—C10	175.9 (5)	C15—C14—O2—C10	−178.9 (6)
C13—C8—C9—C10	−1.5 (8)	C2—C1—S1—C7	179.0 (6)
O1—C9—C10—O2	−1.2 (8)	C6—C1—S1—C7	1.5 (4)
C8—C9—C10—O2	−179.1 (5)	N1—C7—S1—C1	0.0 (4)
O1—C9—C10—C11	−179.8 (5)	C8—C7—S1—C1	176.5 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.88	1.76	2.592 (6)	158
C2—H2···O1ⁱ	0.93	2.55	3.372 (8)	148

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

Experimental details

Crystal data
Chemical formula	C₁₅H₁₃NO₂S
M_r	271.32
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	296
a, b, c (Å)	4.8728 (10), 11.711 (3), 23.378 (6)
V (Å³)	1334.1 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.33 × 0.23 × 0.21

Data collection
Diffractometer	Bruker SMART APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.925, 0.952
No. of measured, independent and observed [I > 2σ(I)] reflections	4083, 2239, 1207
R_int	0.073
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.068, 0.144, 0.99
No. of reflections	2239
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.30
Absolute structure	Flack (1983), 874 Friedel pairs
Absolute structure parameter	−0.1 (2)

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.88	1.76	2.592 (6)	158
C2—H2···O1ⁱ	0.93	2.55	3.372 (8)	148

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

Acknowledgements

HK thanks PNU for financial support. MNT thanks GC University of Sargodha, Pakistan, for the research facility.

References

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