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ISSN: 2056-9890

5-Amino-7-(3-chloro­phen­yl)-3,7-di­hydro-2H-thieno[3,2-b]pyran-6-carbo­nitrile 1,1-dioxide

aXuzhou Institute of Architectural Technology, Xuzhou 221116, People's Republic of China, bSchool of Chemistry and Chemical Engineering, Xuzhou Normal University, Xuzhou 221116, People's Republic of China, and cKey Laboratory of Biotechnology for Medicinal Plants, Xuzhou Normal University, Xuzhou 221116, People's Republic of China
*Correspondence e-mail: chshengyaonk@mail.nankai.edu.cn

(Received 15 December 2009; accepted 23 December 2009; online 9 January 2010)

The title compound, C14H11ClN2O3S, with fused thiophene and pyran rings, was synthesized via the condensation of dihydro­thio­phen-3(2H)-one 1,1-dioxide and 2-(3-chloro­benz­yl­idene)malononitrile catalysed by triethyl­amine in ethanol. The thio­phene ring adopts an envelope conformation and the pyran ring is planar (r.m.s. deviation = 0.0067 Å). The dihedral angle between the pyran and phenyl rings is 80.8 (1)°. The crystal packing is stabilized by inter­molecular N—H⋯N and N—H⋯O hydrogen bonds in which the cyano N and sulphone O atoms, respectively, acting as acceptors.

Related literature

For the use of thienopyranyl compounds, such as thieno[3,2-b]pyran derivatives, as anti­viral agents, see: Friary et al. (1991[Friary, R. J., Schwerdt, J. H. & Ganguly, A. K. (1991). US patent, No. 5034531.]) and as α-2C adrenoreceptor agonists, see: Chao et al. (2009[Chao, J. H., Zheng, J. Y. & Aslanian, R. G. (2009). WO Patent, No. 2009020578.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C14H11ClN2O3S

  • Mr = 322.76

  • Monoclinic, P 21 /c

  • a = 9.5802 (19) Å

  • b = 17.364 (4) Å

  • c = 8.2521 (17) Å

  • β = 97.83 (3)°

  • V = 1360.0 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.45 mm−1

  • T = 113 K

  • 0.20 × 0.18 × 0.12 mm

Data collection
  • Rigaku Saturn CCD area-detector diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA.]) Tmin = 0.916, Tmax = 0.949

  • 9115 measured reflections

  • 2393 independent reflections

  • 1705 reflections with I > 2σ(I)

  • Rint = 0.096

Refinement
  • R[F2 > 2σ(F2)] = 0.053

  • wR(F2) = 0.134

  • S = 1.08

  • 2393 reflections

  • 191 parameters

  • H-atom parameters constrained

  • Δρmax = 0.67 e Å−3

  • Δρmin = −0.49 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2C⋯N1i 0.88 2.20 3.060 (4) 165
N2—H2D⋯O1ii 0.88 2.04 2.912 (4) 174
Symmetry codes: (i) -x+1, -y, -z+1; (ii) x, y, z-1.

Data collection: CrystalClear (Rigaku/MSC, 2005[Rigaku/MSC (2005). CrystalClear. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, can be uesed as antiviral agents (Friary et al., 1991) and α-2 C adrenoreceptor agonists (Chao et al., 2009). This led us to pay attention to the synthesis and bioactivity of these compounds. During the synthesis of thieno[3,2-b]pyran derivatives, the title compound, (I) was isolated and its structure was determined by X-ray diffraction. Here we report its crystal structure.

The molecular structure of (I) is shown in Fig. 1. In the molecular structure, the thiophene ring is in envelope comformation, for the deviation of C1 from the C2/C3/C7/S1 plane is 0.354 (4)Å with r.m.s. of 0.010. The pyrane ring adopts a planar conformation. Cremer & Pople puckering analysis can not be performed, for its weighted average ABS. torsion angle is 1.0°, less than 5.0°. The connection of the pyrane ring and phenyl ring C9—C14 can be described by the C5—C6—C9—C14 torsion angle of 78.3 (3)°. The crystal packing is stabilized by intermolecular hydrogen bonds: N2—H2C···N1, N2—H2D···O1 (Fig.2 & Table 1).

Related literature top

For the use of thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, as antiviral agents, see: Friary et al. (1991) and as α-2C adrenoreceptor agonists, see: Chao et al. (2009). For puckering parameters, see: Cremer & Pople (1975).

Experimental top

The title compound was synthesized by the reaction of dihydrothiophen-3(2H)-one-1,1-dioxide (1 mmol) and 2-(3-chloro benzylidene)malononitrile (1 mmol) catalyzed by triethylamine (0.02 g) in 10 ml ethanol under reluxing until completion (monitored by TLC). Cooling the reaction mixture slowly gave single crystals suitable for X-ray diffraction.

Refinement top

All H atoms were placed in calculated positions, with N–H = 0.88 and C—H = 0.95, 0.99 or 1.00 Å, and included in the final cycles of refinement using a riding model, with Uiso(H) = 1.2Ueq(parent atom).

Structure description top

Thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, can be uesed as antiviral agents (Friary et al., 1991) and α-2 C adrenoreceptor agonists (Chao et al., 2009). This led us to pay attention to the synthesis and bioactivity of these compounds. During the synthesis of thieno[3,2-b]pyran derivatives, the title compound, (I) was isolated and its structure was determined by X-ray diffraction. Here we report its crystal structure.

The molecular structure of (I) is shown in Fig. 1. In the molecular structure, the thiophene ring is in envelope comformation, for the deviation of C1 from the C2/C3/C7/S1 plane is 0.354 (4)Å with r.m.s. of 0.010. The pyrane ring adopts a planar conformation. Cremer & Pople puckering analysis can not be performed, for its weighted average ABS. torsion angle is 1.0°, less than 5.0°. The connection of the pyrane ring and phenyl ring C9—C14 can be described by the C5—C6—C9—C14 torsion angle of 78.3 (3)°. The crystal packing is stabilized by intermolecular hydrogen bonds: N2—H2C···N1, N2—H2D···O1 (Fig.2 & Table 1).

For the use of thienopyranyl compounds, such as thieno [3,2-b]pyran derivatives, as antiviral agents, see: Friary et al. (1991) and as α-2C adrenoreceptor agonists, see: Chao et al. (2009). For puckering parameters, see: Cremer & Pople (1975).

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of (I), showing 30% probability displacement ellipsoids and the atom-numbering scheme.
[Figure 2] Fig. 2. The packing diagram of (I). Intermolecular hydrogen bonds are shown as dashed lines.
5-Amino-7-(3-chlorophenyl)-3,7-dihydro-2H-thieno[3,2-b]pyran- 6-carbonitrile 1,1-dioxide top
Crystal data top
C14H11ClN2O3SF(000) = 664
Mr = 322.76Dx = 1.576 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 4484 reflections
a = 9.5802 (19) Åθ = 2.2–27.9°
b = 17.364 (4) ŵ = 0.45 mm1
c = 8.2521 (17) ÅT = 113 K
β = 97.83 (3)°Block, colorless
V = 1360.0 (5) Å30.20 × 0.18 × 0.12 mm
Z = 4
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2393 independent reflections
Radiation source: rotating anode1705 reflections with I > 2σ(I)
Confocal monochromatorRint = 0.096
Detector resolution: 7.31 pixels mm-1θmax = 25.0°, θmin = 2.2°
ω and φ scansh = 1111
Absorption correction: multi-scan
CrystalClear
k = 1920
Tmin = 0.916, Tmax = 0.949l = 99
9115 measured reflections
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)] = 0.053H-atom parameters constrained
wR(F2) = 0.134 w = 1/[σ2(Fo2) + (0.0583P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max < 0.001
2393 reflectionsΔρmax = 0.67 e Å3
191 parametersΔρmin = 0.49 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.491 (16)
Crystal data top
C14H11ClN2O3SV = 1360.0 (5) Å3
Mr = 322.76Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.5802 (19) ŵ = 0.45 mm1
b = 17.364 (4) ÅT = 113 K
c = 8.2521 (17) Å0.20 × 0.18 × 0.12 mm
β = 97.83 (3)°
Data collection top
Rigaku Saturn CCD area-detector
diffractometer
2393 independent reflections
Absorption correction: multi-scan
CrystalClear
1705 reflections with I > 2σ(I)
Tmin = 0.916, Tmax = 0.949Rint = 0.096
9115 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0530 restraints
wR(F2) = 0.134H-atom parameters constrained
S = 1.08Δρmax = 0.67 e Å3
2393 reflectionsΔρmin = 0.49 e Å3
191 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
S10.01194 (8)0.13574 (4)0.99300 (11)0.0141 (3)
Cl10.69314 (8)0.15345 (5)1.25118 (11)0.0240 (3)
O10.0062 (2)0.07472 (12)1.1133 (3)0.0189 (6)
O20.0250 (2)0.21172 (12)1.0529 (3)0.0220 (7)
O30.0422 (2)0.09320 (11)0.5466 (3)0.0143 (6)
N20.2045 (3)0.05206 (14)0.3987 (3)0.0173 (7)
H2C0.28840.03610.38170.021*
H2D0.13670.05690.31590.021*
N10.5321 (3)0.03147 (15)0.6812 (4)0.0206 (7)
C10.1785 (3)0.13702 (17)0.8638 (4)0.0157 (8)
H1A0.23260.08980.88020.019*
H1B0.23460.18220.88920.019*
C20.1464 (3)0.14131 (16)0.6882 (4)0.0131 (8)
H2A0.21240.10850.61550.016*
H2B0.15450.19500.64740.016*
C30.0022 (3)0.11258 (17)0.6944 (4)0.0128 (8)
C40.1798 (3)0.06909 (16)0.5505 (4)0.0118 (7)
C50.2722 (3)0.06488 (17)0.6910 (4)0.0119 (7)
C60.2351 (3)0.08436 (16)0.8608 (4)0.0119 (7)
H60.24580.03700.93050.014*
C70.0834 (3)0.10851 (16)0.8370 (4)0.0102 (7)
C80.4147 (3)0.04538 (16)0.6824 (4)0.0138 (8)
C90.3344 (3)0.14675 (16)0.9401 (4)0.0126 (8)
C100.4501 (3)0.12565 (18)1.0523 (4)0.0144 (8)
H100.46400.07331.08390.017*
C110.5450 (3)0.18159 (19)1.1175 (4)0.0153 (8)
C120.5249 (3)0.25793 (18)1.0762 (4)0.0183 (8)
H120.58930.29601.12330.022*
C130.4088 (3)0.27859 (18)0.9644 (4)0.0168 (8)
H130.39410.33120.93510.020*
C140.3145 (3)0.22355 (17)0.8953 (4)0.0154 (8)
H140.23650.23820.81770.018*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0099 (5)0.0182 (5)0.0140 (6)0.0013 (3)0.0011 (4)0.0018 (3)
Cl10.0124 (5)0.0361 (6)0.0215 (6)0.0006 (3)0.0051 (4)0.0020 (4)
O10.0173 (13)0.0255 (13)0.0136 (15)0.0041 (9)0.0015 (11)0.0050 (10)
O20.0201 (13)0.0191 (13)0.0280 (17)0.0022 (9)0.0073 (12)0.0113 (11)
O30.0094 (12)0.0199 (13)0.0136 (14)0.0039 (9)0.0018 (10)0.0007 (10)
N20.0100 (14)0.0277 (16)0.0137 (18)0.0025 (12)0.0008 (13)0.0038 (13)
N10.0137 (16)0.0291 (16)0.0185 (19)0.0042 (12)0.0008 (13)0.0018 (14)
C10.0081 (17)0.0228 (18)0.015 (2)0.0021 (12)0.0006 (15)0.0022 (14)
C20.0086 (17)0.0147 (17)0.016 (2)0.0026 (12)0.0004 (15)0.0006 (13)
C30.0128 (17)0.0104 (16)0.016 (2)0.0000 (12)0.0048 (15)0.0000 (14)
C40.0095 (16)0.0117 (16)0.015 (2)0.0008 (12)0.0035 (15)0.0004 (14)
C50.0095 (17)0.0144 (16)0.012 (2)0.0026 (12)0.0027 (15)0.0003 (14)
C60.0106 (17)0.0149 (16)0.010 (2)0.0024 (12)0.0004 (15)0.0002 (13)
C70.0081 (16)0.0109 (15)0.012 (2)0.0008 (12)0.0028 (14)0.0003 (14)
C80.0182 (19)0.0133 (17)0.010 (2)0.0004 (13)0.0006 (15)0.0002 (13)
C90.0072 (17)0.0187 (17)0.012 (2)0.0004 (12)0.0027 (15)0.0031 (14)
C100.0138 (18)0.0163 (17)0.014 (2)0.0018 (13)0.0032 (16)0.0002 (14)
C110.0075 (16)0.0268 (19)0.011 (2)0.0012 (13)0.0009 (15)0.0019 (15)
C120.0118 (18)0.0242 (19)0.020 (2)0.0045 (13)0.0059 (16)0.0060 (15)
C130.0156 (18)0.0167 (17)0.019 (2)0.0010 (13)0.0070 (16)0.0016 (15)
C140.0094 (16)0.0205 (18)0.016 (2)0.0032 (13)0.0017 (14)0.0004 (15)
Geometric parameters (Å, º) top
S1—O21.436 (2)C3—C71.322 (5)
S1—O11.448 (2)C4—C51.361 (5)
S1—C71.742 (3)C5—C81.418 (4)
S1—C11.794 (3)C5—C61.529 (4)
Cl1—C111.745 (3)C6—C71.499 (4)
O3—C31.369 (4)C6—C91.529 (4)
O3—C41.379 (4)C6—H61.0000
N2—C41.339 (4)C9—C141.390 (4)
N2—H2C0.8800C9—C101.393 (5)
N2—H2D0.8800C10—C111.388 (4)
N1—C81.152 (4)C10—H100.9500
C1—C21.523 (5)C11—C121.376 (4)
C1—H1A0.9900C12—C131.392 (5)
C1—H1B0.9900C12—H120.9500
C2—C31.503 (4)C13—C141.383 (4)
C2—H2A0.9900C13—H130.9500
C2—H2B0.9900C14—H140.9500
O2—S1—O1116.86 (15)C8—C5—C6116.4 (3)
O2—S1—C7111.96 (13)C7—C6—C9113.2 (2)
O1—S1—C7109.44 (13)C7—C6—C5106.5 (3)
O2—S1—C1110.54 (14)C9—C6—C5109.9 (2)
O1—S1—C1111.37 (14)C7—C6—H6109.1
C7—S1—C194.45 (15)C9—C6—H6109.1
C3—O3—C4115.9 (3)C5—C6—H6109.1
C4—N2—H2C120.0C3—C7—C6125.1 (3)
C4—N2—H2D120.0C3—C7—S1109.8 (2)
H2C—N2—H2D120.0C6—C7—S1125.1 (3)
C2—C1—S1106.7 (2)N1—C8—C5177.0 (4)
C2—C1—H1A110.4C14—C9—C10119.8 (3)
S1—C1—H1A110.4C14—C9—C6120.7 (3)
C2—C1—H1B110.4C10—C9—C6119.4 (3)
S1—C1—H1B110.4C11—C10—C9119.6 (3)
H1A—C1—H1B108.6C11—C10—H10120.2
C3—C2—C1105.3 (3)C9—C10—H10120.2
C3—C2—H2A110.7C12—C11—C10121.1 (3)
C1—C2—H2A110.7C12—C11—Cl1120.0 (3)
C3—C2—H2B110.7C10—C11—Cl1118.9 (2)
C1—C2—H2B110.7C11—C12—C13119.0 (3)
H2A—C2—H2B108.8C11—C12—H12120.5
C7—C3—O3125.3 (3)C13—C12—H12120.5
C7—C3—C2119.2 (3)C14—C13—C12120.9 (3)
O3—C3—C2115.5 (3)C14—C13—H13119.6
N2—C4—C5127.5 (3)C12—C13—H13119.6
N2—C4—O3109.6 (3)C13—C14—C9119.7 (3)
C5—C4—O3123.0 (3)C13—C14—H14120.2
C4—C5—C8119.2 (3)C9—C14—H14120.2
C4—C5—C6124.3 (3)
O2—S1—C1—C297.0 (2)C9—C6—C7—S160.0 (3)
O1—S1—C1—C2131.35 (19)C5—C6—C7—S1179.2 (2)
C7—S1—C1—C218.5 (2)O2—S1—C7—C3104.5 (2)
S1—C1—C2—C321.1 (3)O1—S1—C7—C3124.3 (2)
C4—O3—C3—C71.3 (4)C1—S1—C7—C39.8 (2)
C4—O3—C3—C2178.0 (2)O2—S1—C7—C675.3 (3)
C1—C2—C3—C716.2 (4)O1—S1—C7—C655.9 (3)
C1—C2—C3—O3164.4 (2)C1—S1—C7—C6170.4 (3)
C3—O3—C4—N2180.0 (2)C4—C5—C8—N1149 (7)
C3—O3—C4—C50.4 (4)C6—C5—C8—N128 (7)
N2—C4—C5—C84.5 (5)C7—C6—C9—C1440.6 (4)
O3—C4—C5—C8175.0 (2)C5—C6—C9—C1478.3 (3)
N2—C4—C5—C6179.1 (3)C7—C6—C9—C10142.6 (3)
O3—C4—C5—C61.4 (5)C5—C6—C9—C1098.5 (3)
C4—C5—C6—C70.6 (4)C14—C9—C10—C110.4 (5)
C8—C5—C6—C7175.8 (3)C6—C9—C10—C11176.3 (3)
C4—C5—C6—C9123.5 (3)C9—C10—C11—C121.6 (5)
C8—C5—C6—C952.9 (3)C9—C10—C11—Cl1177.3 (2)
O3—C3—C7—C62.1 (5)C10—C11—C12—C131.4 (5)
C2—C3—C7—C6177.2 (3)Cl1—C11—C12—C13177.5 (2)
O3—C3—C7—S1178.1 (2)C11—C12—C13—C140.1 (5)
C2—C3—C7—S12.6 (4)C12—C13—C14—C91.1 (5)
C9—C6—C7—C3119.8 (4)C10—C9—C14—C130.9 (4)
C5—C6—C7—C31.0 (4)C6—C9—C14—C13177.6 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2C···N1i0.882.203.060 (4)165
N2—H2D···O1ii0.882.042.912 (4)174
Symmetry codes: (i) x+1, y, z+1; (ii) x, y, z1.

Experimental details

Crystal data
Chemical formulaC14H11ClN2O3S
Mr322.76
Crystal system, space groupMonoclinic, P21/c
Temperature (K)113
a, b, c (Å)9.5802 (19), 17.364 (4), 8.2521 (17)
β (°) 97.83 (3)
V3)1360.0 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.45
Crystal size (mm)0.20 × 0.18 × 0.12
Data collection
DiffractometerRigaku Saturn CCD area-detector
Absorption correctionMulti-scan
CrystalClear
Tmin, Tmax0.916, 0.949
No. of measured, independent and
observed [I > 2σ(I)] reflections
9115, 2393, 1705
Rint0.096
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.053, 0.134, 1.08
No. of reflections2393
No. of parameters191
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.67, 0.49

Computer programs: CrystalClear (Rigaku/MSC, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2C···N1i0.882.203.060 (4)165.0
N2—H2D···O1ii0.882.042.912 (4)174.1
Symmetry codes: (i) x+1, y, z+1; (ii) x, y, z1.
 

Acknowledgements

The authors acknowledge financial support by the Graduate Foundation of Xuzhou Normal University (No. 09YLB030).

References

First citationChao, J. H., Zheng, J. Y. & Aslanian, R. G. (2009). WO Patent, No. 2009020578.  Google Scholar
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