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

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2-[2-(4-Methyl­benzo­yl)-3,3-bis­­(methyl­sulfan­yl)prop-2-enyl­­idene]malono­nitrile

aSchool of Pure and Applied Physics, Mahatma Gandhi University, Kottayam, Kerala, India, and bSchool of Chemical Sciences, Mahatma Gandhi University, Kottayam, Kerala, India
*Correspondence e-mail: csudarsan1@sify.com

(Received 25 November 2007; accepted 7 February 2008; online 15 February 2008)

The title compound, C16H14N2OS2, is an example of a push–pull butadiene in which the electron-releasing and electron-withdrawing attachments on either end of the butadiene chain enhance the conjugation in the system. The mol­ecules are linked by inter­molecular C—H⋯N inter­actions.

Related literature

For related literature, see: Anabha & Asokan (2006[Anabha, E. R. & Asokan, C. V. (2006). Synthesis, 1, 151-155.]); Dahne (1978[Dahne, S. (1978). Science, 199, 1163-1167.]); Dastidar et al. (1993[Dastidar, P., Guru Row, T. N. & Venkatesan, K. (1993). Acta Cryst. B49, 900-905.]); Freier et al. (1999[Freier, T., Michalik, M. & Peseke, K. (1999). J. Chem. Soc. Perkin Trans. 2, pp. 1265-1271.]); Homrig­hausen & Krause Bauer (2004[Homrighausen, C. L. & Krause Bauer, J. A. (2004). Acta Cryst. E60, o1828-o1829.]); Michalik et al. (2002[Michalik, M., Freier, T., Reinke, H. & Peseke, K. (2002). J. Chem. Soc. Perkin Trans. 2, pp. 114-119.]).

[Scheme 1]

Experimental

Crystal data
  • C16H14N2OS2

  • Mr = 314.41

  • Monoclinic, C 2

  • a = 16.6050 (13) Å

  • b = 10.760 (2) Å

  • c = 9.905 (2) Å

  • β = 110.09 (2)°

  • V = 1662.0 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.32 mm−1

  • T = 295 (2) K

  • 0.25 × 0.25 × 0.20 mm

Data collection
  • MacScience DIPLabo 32001 diffractometer

  • Absorption correction: none

  • 4433 measured reflections

  • 2717 independent reflections

  • 2583 reflections with I > 2σ(I)

  • Rint = 0.035

Refinement
  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.156

  • S = 1.11

  • 2717 reflections

  • 194 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.28 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), with 1210 Friedel pairs

  • Flack parameter: 0.11 (12)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C12—H12B⋯N2i 0.96 2.49 3.3871 155
Symmetry code: (i) [x-{\script{1\over 2}}, y-{\script{1\over 2}}, z-1].

Data collection: XPRESS (MacScience, 2002[MacScience (2002). XPRESS. MacScience Co. Ltd, Yokohama, Japan.]); cell refinement: SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); 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: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]) and ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97 and PLATON.

Supporting information


Comment top

Due to the presence of electron releasing alkyl sulfanyl groups and electron withdrawing nitrile groups on the terminal carbon atoms of butadiene moiety, these molecules are considered as push pull butadienes. The push pull substitution alters the polyene state of the unsubstituted butadiene with balanced pi-charge distribution to a polymethine structure with alternating charge densities at the carbon atoms (Dahne, 1978). The title compound, (I), was synthesized and its crystal structure determination was carried out in order to elucidate the molecular conformation to understand the influence of aroyl groups on the stereochemistry of the butadiene molecule in continuation of research in the synthesis of pyridine derivatives (Anabha & Asokan, 2006). A perspective view of (I) is shown in Fig. 1. The crystal structure of (I) shows that the double bonds in the aroyl substituted butadiene are arranged in a transoid manner. Bond lengths C9—C10 and C13—C14 indicate their double bond character while C8—C9 is a single bond. Moreover, the double bonds C9—C10 and C13—C14 and shortening of C10—S2 bond length shows the electronic effects on the push pull system. Crystal structures of other butadiene compounds reported also show similar geometric parameters (Dastidar et al., 1993; Michalik et al., 2002; Freier et al., 1999; Homrighausen & Krause Bauer, 2004). The hydrogen-bond interactions of the type C—H···N stabilize the three dimensional structure along the ac plane (Fig. 2).

Related literature top

For related literature, see: Anabha & Asokan (2006); Dahne (1978); Dastidar et al. (1993); Freier et al. (1999); Homrighausen & Krause Bauer (2004); Michalik et al. (2002).

Experimental top

2-[3,3-Bis(methyl sulfanyl)-2-(4-methyl benzoyl)-2- propylidene] malononitrile was obtained by the Knoevenagel condensation reaction of 3,3-bis (methyl sulfanyl)-2-(4-methyl benzoyl)-acrylaldehyde (1.33 g., 5 mmol) with malononitrile (500 mg., 7.5 mmol) (Anabha et al., 2006). Single crystals suitable for X-ray diffraction studies were grown by slow evaporation using solutions containing chloroform and hexane in the ratio 1:2. Pale yellow coloured crystals were obtained after two days.

Refinement top

The position of all H atoms were geometrically fixed and treated with riding atoms, with C—H distances of 0.93 or 0.96 A. Their isotropic displacement parameters were defined as Uiso= 1.5Ueq of the adjacent atom for the methyl H atoms and Uiso = 1.2Ueq for all other atoms. The 1210 Friedel opposites were not merged, and the choice of absolute structure was determined by the Flack parameter (Flack, 1983) of 0.11 (12). For the inverted structure the Flack parameter refined to 0.84 (12).

Computing details top

Data collection: XPRESS (Mac Science, 2002); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003) and ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. An ORTEPII (Johnson, 1976) view of (I) showing the atom-labeling scheme; displacement ellipsoids are drawn at 50% probability level.
[Figure 2] Fig. 2. A view of the unit cell packing of (I) showing intermolecular interactions in the ac plane.
2-[2-(4-Methylbenzoyl)-3,3-bis(methylsulfanyl)prop-2-enylidene]malononitrile top
Crystal data top
C16H14N2OS2F(000) = 656
Mr = 314.41Dx = 1.257 Mg m3
Monoclinic, C2Mo Kα radiation, λ = 0.71070 Å
Hall symbol: C 2yCell parameters from 4224 reflections
a = 16.6050 (13) Åθ = 3.5–25.5°
b = 10.760 (2) ŵ = 0.32 mm1
c = 9.905 (2) ÅT = 295 K
β = 110.09 (2)°Block, pale yellow
V = 1662.0 (5) Å30.25 × 0.25 × 0.20 mm
Z = 4
Data collection top
MacScience DIPLabo 32001
diffractometer
2583 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.035
Graphite monochromatorθmax = 25.5°, θmin = 3.5°
Detector resolution: 10.0 pixels mm-1h = 2020
ω scansk = 1111
4433 measured reflectionsl = 1111
2717 independent reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.049 w = 1/[σ2(Fo2) + (0.1066P)2 + 0.5386P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.156(Δ/σ)max < 0.001
S = 1.11Δρmax = 0.30 e Å3
2717 reflectionsΔρmin = 0.28 e Å3
194 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
1 restraintExtinction coefficient: 0.015 (3)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983)
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.11 (12)
Crystal data top
C16H14N2OS2V = 1662.0 (5) Å3
Mr = 314.41Z = 4
Monoclinic, C2Mo Kα radiation
a = 16.6050 (13) ŵ = 0.32 mm1
b = 10.760 (2) ÅT = 295 K
c = 9.905 (2) Å0.25 × 0.25 × 0.20 mm
β = 110.09 (2)°
Data collection top
MacScience DIPLabo 32001
diffractometer
2583 reflections with I > 2σ(I)
4433 measured reflectionsRint = 0.035
2717 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.049H-atom parameters constrained
wR(F2) = 0.156Δρmax = 0.30 e Å3
S = 1.11Δρmin = 0.28 e Å3
2717 reflectionsAbsolute structure: Flack (1983)
194 parametersAbsolute structure parameter: 0.11 (12)
1 restraint
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
S10.33194 (6)0.02065 (9)0.76965 (9)0.0543 (3)
S20.16024 (7)0.08895 (12)0.75086 (11)0.0689 (4)
C50.1681 (2)0.0204 (3)1.1171 (4)0.0458 (8)
C130.3562 (2)0.0395 (4)1.0845 (3)0.0471 (7)
H130.38010.09251.03440.057*
C90.2833 (2)0.0289 (3)0.9991 (3)0.0430 (7)
C80.2276 (2)0.0956 (4)1.0693 (3)0.0471 (8)
C140.3959 (2)0.0379 (4)1.2301 (3)0.0508 (8)
C100.2604 (2)0.0317 (3)0.8523 (4)0.0468 (7)
O10.2346 (2)0.2092 (3)1.0871 (3)0.0680 (8)
C40.1194 (3)0.0773 (4)1.1895 (5)0.0622 (10)
H40.12280.16281.20410.075*
C60.1602 (3)0.1060 (4)1.0927 (5)0.0592 (10)
H60.19160.14471.04280.071*
C160.4673 (2)0.1193 (4)1.2927 (4)0.0553 (9)
C150.3732 (3)0.0373 (4)1.3306 (4)0.0588 (10)
C30.0660 (3)0.0065 (5)1.2394 (5)0.0716 (12)
H30.03410.04521.28820.086*
C20.0592 (3)0.1204 (6)1.2184 (5)0.0729 (13)
N10.3560 (3)0.0944 (5)1.4132 (4)0.0905 (14)
N20.5237 (3)0.1858 (5)1.3400 (5)0.0795 (12)
C110.2658 (3)0.1102 (5)0.6206 (5)0.0724 (12)
H11A0.23910.05620.54050.109*
H11B0.30030.17050.59420.109*
H11C0.22230.15210.64700.109*
C120.1815 (4)0.1799 (6)0.6150 (5)0.0828 (15)
H12A0.19700.12580.55080.124*
H12B0.13110.22610.56200.124*
H12C0.22780.23640.65950.124*
C70.1061 (3)0.1753 (5)1.1419 (6)0.0738 (13)
H70.10080.26021.12360.089*
C10.0013 (5)0.2004 (8)1.2746 (9)0.105 (2)
H1A0.05390.16161.25100.157*
H1B0.00520.28121.23110.157*
H1C0.02670.20851.37710.157*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0555 (5)0.0664 (6)0.0453 (5)0.0047 (4)0.0227 (4)0.0002 (4)
S20.0532 (5)0.0949 (9)0.0551 (5)0.0188 (5)0.0141 (4)0.0181 (5)
C50.0452 (17)0.046 (2)0.0481 (17)0.0059 (12)0.0189 (14)0.0031 (13)
C130.0479 (16)0.054 (2)0.0413 (16)0.0045 (14)0.0172 (13)0.0025 (13)
C90.0473 (17)0.0434 (18)0.0393 (15)0.0042 (12)0.0162 (13)0.0027 (11)
C80.0526 (18)0.049 (2)0.0410 (16)0.0073 (14)0.0176 (14)0.0026 (13)
C140.0494 (17)0.063 (2)0.0405 (15)0.0010 (16)0.0163 (13)0.0063 (15)
C100.0491 (18)0.0487 (19)0.0456 (17)0.0060 (13)0.0202 (14)0.0053 (13)
O10.090 (2)0.0475 (19)0.081 (2)0.0027 (14)0.0481 (17)0.0039 (13)
C40.062 (2)0.062 (3)0.072 (2)0.0035 (18)0.036 (2)0.0115 (19)
C60.053 (2)0.052 (3)0.077 (3)0.0072 (15)0.0284 (19)0.0051 (17)
C160.0472 (19)0.071 (2)0.0447 (18)0.0072 (17)0.0118 (15)0.0098 (16)
C150.062 (2)0.065 (3)0.0454 (18)0.0017 (17)0.0130 (16)0.0001 (17)
C30.069 (3)0.076 (4)0.085 (3)0.0031 (19)0.047 (2)0.010 (2)
C20.052 (2)0.090 (4)0.079 (3)0.002 (2)0.026 (2)0.024 (2)
N10.104 (3)0.112 (4)0.052 (2)0.021 (3)0.023 (2)0.015 (2)
N20.062 (2)0.105 (4)0.065 (2)0.020 (2)0.0144 (19)0.016 (2)
C110.083 (3)0.077 (3)0.056 (2)0.003 (2)0.024 (2)0.016 (2)
C120.089 (3)0.096 (4)0.060 (3)0.033 (3)0.022 (2)0.026 (2)
C70.071 (3)0.052 (3)0.107 (4)0.0002 (18)0.041 (3)0.010 (2)
C10.090 (4)0.104 (5)0.140 (6)0.002 (3)0.065 (4)0.036 (4)
Geometric parameters (Å, º) top
S1—C101.751 (3)C6—H60.9300
S1—C111.790 (5)C16—N21.142 (6)
S2—C101.734 (3)C15—N11.135 (6)
S2—C121.795 (5)C3—C21.381 (8)
C5—C61.379 (6)C3—H30.9300
C5—C41.393 (5)C2—C71.390 (7)
C5—C81.475 (5)C2—C11.531 (7)
C13—C141.364 (5)C11—H11A0.9600
C13—C91.421 (5)C11—H11B0.9600
C13—H130.9300C11—H11C0.9600
C9—C101.372 (5)C12—H12A0.9600
C9—C81.515 (4)C12—H12B0.9600
C8—O11.235 (5)C12—H12C0.9600
C14—C151.430 (6)C7—H70.9300
C14—C161.433 (5)C1—H1A0.9600
C4—C31.383 (6)C1—H1B0.9600
C4—H40.9300C1—H1C0.9600
C6—C71.380 (6)
C10—S1—C11103.7 (2)C2—C3—C4121.4 (4)
C10—S2—C12103.4 (2)C2—C3—H3119.3
C6—C5—C4119.2 (4)C4—C3—H3119.3
C6—C5—C8121.2 (3)C3—C2—C7118.0 (4)
C4—C5—C8119.6 (3)C3—C2—C1122.0 (5)
C14—C13—C9128.7 (3)C7—C2—C1119.9 (6)
C14—C13—H13115.6S1—C11—H11A109.5
C9—C13—H13115.6S1—C11—H11B109.5
C10—C9—C13120.8 (3)H11A—C11—H11B109.5
C10—C9—C8119.1 (3)S1—C11—H11C109.5
C13—C9—C8120.1 (3)H11A—C11—H11C109.5
O1—C8—C5122.6 (3)H11B—C11—H11C109.5
O1—C8—C9119.4 (3)S2—C12—H12A109.5
C5—C8—C9118.0 (3)S2—C12—H12B109.5
C13—C14—C15126.6 (3)H12A—C12—H12B109.5
C13—C14—C16118.5 (3)S2—C12—H12C109.5
C15—C14—C16115.0 (3)H12A—C12—H12C109.5
C9—C10—S2118.9 (3)H12B—C12—H12C109.5
C9—C10—S1120.2 (3)C6—C7—C2121.2 (5)
S2—C10—S1120.88 (19)C6—C7—H7119.4
C3—C4—C5119.9 (4)C2—C7—H7119.4
C3—C4—H4120.1C2—C1—H1A109.5
C5—C4—H4120.1C2—C1—H1B109.5
C5—C6—C7120.3 (4)H1A—C1—H1B109.5
C5—C6—H6119.9C2—C1—H1C109.5
C7—C6—H6119.9H1A—C1—H1C109.5
N2—C16—C14178.5 (5)H1B—C1—H1C109.5
N1—C15—C14178.0 (5)
C14—C13—C9—C10169.0 (4)C8—C9—C10—S1169.0 (3)
C14—C13—C9—C813.6 (6)C12—S2—C10—C9138.8 (3)
C6—C5—C8—O1178.5 (4)C12—S2—C10—S140.6 (3)
C4—C5—C8—O12.1 (6)C11—S1—C10—C9136.9 (3)
C6—C5—C8—C93.1 (5)C11—S1—C10—S243.7 (3)
C4—C5—C8—C9176.3 (3)C6—C5—C4—C31.9 (6)
C10—C9—C8—O180.2 (5)C8—C5—C4—C3177.5 (4)
C13—C9—C8—O1102.4 (4)C4—C5—C6—C71.3 (7)
C10—C9—C8—C5101.3 (4)C8—C5—C6—C7178.1 (4)
C13—C9—C8—C576.1 (4)C5—C4—C3—C20.5 (7)
C9—C13—C14—C151.7 (6)C4—C3—C2—C71.6 (8)
C9—C13—C14—C16177.8 (4)C4—C3—C2—C1179.2 (5)
C13—C9—C10—S2167.0 (3)C5—C6—C7—C20.9 (8)
C8—C9—C10—S210.4 (5)C3—C2—C7—C62.3 (8)
C13—C9—C10—S113.6 (5)C1—C2—C7—C6178.5 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12B···N2i0.962.493.3871155
Symmetry code: (i) x1/2, y1/2, z1.

Experimental details

Crystal data
Chemical formulaC16H14N2OS2
Mr314.41
Crystal system, space groupMonoclinic, C2
Temperature (K)295
a, b, c (Å)16.6050 (13), 10.760 (2), 9.905 (2)
β (°) 110.09 (2)
V3)1662.0 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.32
Crystal size (mm)0.25 × 0.25 × 0.20
Data collection
DiffractometerMacScience DIPLabo 32001
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
4433, 2717, 2583
Rint0.035
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.156, 1.11
No. of reflections2717
No. of parameters194
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.30, 0.28
Absolute structureFlack (1983)
Absolute structure parameter0.11 (12)

Computer programs: XPRESS (Mac Science, 2002), SCALEPACK (Otwinowski & Minor, 1997), SCALEPACK and DENZO (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), PLATON (Spek, 2003) and ORTEPII (Johnson, 1976), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C12—H12B···N2i0.962.493.3871155
Symmetry code: (i) x1/2, y1/2, z1.
 

Acknowledgements

The authors acknowledge the National Single Crystal Diffractometer Facility, Department of Studies in Physics, University of Mysore, Manasagangothri, for help with the data collection. One of the authors (JN) is grateful to UGC, New Delhi, Government of India, for providing a teaching fellowship.

References

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