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Acta Cryst. (2009). E65, o71    [ doi:10.1107/S1600536808041007 ]

4-(3-Ethoxy-4-hydroxystyryl)-1-methylpyridinium tosylate monohydrate

S. Murugavel, A. SubbiahPandi, C. Srikanth and S. Kalainathan

Abstract top

In the title compound, C16H18NO2+·C7H7O3S-·H2O, the dihedral angle between the pyridyl and benzene rings of the pyridinium cation is 0.2 (1)°. The benzene ring of the tosylate anion makes a dihedral angle of 4.8 (2)° with the best mean plane of the pyridinium cation. The pyridinium cation and the tosylate anion are hydrogen bonded to the water molecule, and the crystal packing is further stabilized by intermolecular C-H...O and [pi]-[pi] interactions [centroid-centroid separations of 3.648 (3) and 3.594 (2) Å.

Comment top

The synthesis and study of molecular compounds with non linear optical (NLO) properties has attracted much attention, because such materials hold promise for applications in optoelectronic and photonic devices (Bosshard et al., 1995; Nalwa & Miyata, 1997). In order to create efficient quadratic (second–order) NLO materials, both the molecular and bulk properties must be optimized. Within the diverse range of existing NLO compounds, styrylpyridinium salts are particularly attractive for device applications (Lee & Kim, 1999). Against this background, and in order to obtain detailed information on molecular conformations in the solid state, X-ray studies of the title compounds (I) have been carried out.

X-Ray analysis confirms the molecular structure and atom connectivity for (I), as illustrated in Fig. 1. The dihedral angle between the pyridyl and phenyl rings of the pyridinium cation is 0.2 (1)°. The benzene ring of the tosylate anion makes a dihedral angle of 4.8 (2)° with the best mean plane of the pyridinium cation. The bond lengths N1–C7, C13–O25 and C14–O26 are normal and comparable with the corresponding values observed in the related structure. (Zhang et al., 1997)

The presence of water molecules in the crystal structure of (I) leads to a three dimensional network of hydrogen bonds invoving water, the tosylate anion and the pyridinium cation (Table 1). In addition, the crystal packing is further stabilized by intermolecular C—H···O (Table.1) and π—π interactions with a Cg1···Cg1i and a Cg1—Cg2ii separation of 3.648 (3) Å and 3.594 Å, respectively (Fig. 2; Cg1 and Cg2 are the centroids of the N/C1-C5 pyridine ring and C17-C22 benzene ring, respectively, symmetry code as in Fig. 2).

Related literature top

For related structure, see: Zhang et al. (1997). For molecular compounds with non-linear

optical (NLO) properties, see: Bosshard et al. (1995); Nalwa & Miyata (1997); Lee & Kim (1999).

Experimental top

HEST (4-[2-(4-hydroxy-3-ethoxyphenyl) ethenyl]-1-methylpyridinium 4-tolylsulfonate hydrate ) was synthesized by the condensation of 4-methyl N-methyl pyridinum Tosylate, which is prepared from 4-Picoline (Merck, 99%) , methyl toluene sulphonate (Merck, 98%) and 4-hydroxy-3-ethoxy-Benzaldehyde (High Media, 98%) in the presence of piperidine as catalyst. The step by step synthesis procedure of HEST is as follows: Picoline (10.31 ml, 0.105 mol %) and methyl toluene sulphonate (15.88 ml, 0.105 mol %) is added into toluene (200ml) (Merck, 98%) is taken in a round bottom flask (500 ml) of Dean-stark apparatus. This mixture is heated until formation of white salt, which is insoluble in toluene. While boiling Di-methyl formamide (DMF) (Merck, 98%) is added until the white salt are dissolved. Now 4-hydroxy-3-ethoxy-Benzaldehyde (0.105 mol %) is added. Few drops of Piperidine also added as catalyst. The mixture is then refluxed with Dean-stark trap to remove water. After more than equivalent amount of water is collected, the reactants are cooled to room temperature and synthesized orange color HEST is collected. To prevent the absorption of water from the atmosphere, the synthesized material is placed in the oven at 100°C for 1 hour. Purified single crystals suitable for X-ray diffraction was obtained by successive recrystallization process of a methonal solution.

Refinement top

H atoms of the water were located in a difference fourier map, and were refined with distance restraints of O—H = 0.85(0.01) Å and H···H = 1.25(0.01) Å and all other H atoms were fixed geometrically and allowed to ride on their parent atoms, with C—H = 0.93–0.98 Å with Uiso(H)= 1.5Ueq (methyl H) and 1.2Ueq (for other H atoms).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of title compound showing 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. 2. π—π interactions (dotted lines) in the title compound. Cg denotes ring centroid. [Symmetry code: (i) -x+1, -y, -z+1; (ii) x, y-1, z; (iii) x, y+1, z; (iv) -x+1, -y+1, -z+1.]
4-(3-Ethoxy-4-hydroxystyryl)-1-methylpyridinium tosylate monohydrate top
Crystal data top
C16H18NO2+·C7H7O3S−·H2OF(000) = 944
Mr = 445.52Dx = 1.315 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 5318 reflections
a = 13.7700 (4) Åθ = 2.2–27.8°
b = 9.7125 (2) ŵ = 0.18 mm−1
c = 17.3394 (5) ÅT = 293 K
β = 104.059 (2)°Block, orange
V = 2249.53 (10) Å30.25 × 0.17 × 0.16 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer		5310 independent reflections
Radiation source: fine-focus sealed tube3610 reflections with I > 2σ(I)
graphiteRint = 0.034
Detector resolution: 10 pixels mm-1θmax = 27.8°, θmin = 2.2°
ω scansh = −18→18
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		k = −12→12
Tmin = 0.961, Tmax = 0.975l = −22→22
48719 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.057Hydrogen site location: difference Fourier map
wR(F2) = 0.187H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0893P)2 + 1.1253P]
where P = (Fo2 + 2Fc2)/3
5310 reflections(Δ/σ)max < 0.001
290 parametersΔρmax = 0.72 e Å−3
3 restraintsΔρmin = −0.30 e Å−3
Crystal data top
C16H18NO2+·C7H7O3S−·H2OV = 2249.53 (10) Å3
Mr = 445.52Z = 4
Monoclinic, P21/nMo Kα radiation
a = 13.7700 (4) ŵ = 0.18 mm−1
b = 9.7125 (2) ÅT = 293 K
c = 17.3394 (5) Å0.25 × 0.17 × 0.16 mm
β = 104.059 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer		5310 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		3610 reflections with I > 2σ(I)
Tmin = 0.961, Tmax = 0.975Rint = 0.034
48719 measured reflectionsθmax = 27.8°
Refinement top
R[F2 > 2σ(F2)] = 0.057H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.187Δρmax = 0.72 e Å−3
S = 1.03Δρmin = −0.30 e Å−3
5310 reflectionsAbsolute structure: ?
290 parametersFlack parameter: ?
3 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
S0.72581 (5)0.48936 (6)0.59449 (4)0.0646 (2)
O10.92457 (12)0.27591 (17)0.20090 (10)0.0589 (4)
H1O0.92480.22130.16490.088*
O20.91242 (13)0.42417 (17)0.32358 (10)0.0604 (4)
O30.62950 (16)0.5133 (2)0.61455 (17)0.0998 (8)
O40.78329 (17)0.3912 (2)0.64784 (16)0.0958 (8)
O50.7116 (2)0.4619 (2)0.51204 (15)0.1024 (8)
O60.44858 (19)0.3921 (3)0.58789 (15)0.0855 (6)
H6OA0.399 (2)0.427 (3)0.5530 (19)0.16 (2)*
H6OB0.4608 (18)0.4682 (16)0.6128 (13)0.050 (7)*
N0.55785 (13)−0.0896 (2)0.63677 (11)0.0514 (5)
C10.56915 (16)−0.1585 (2)0.57240 (14)0.0515 (5)
H10.5445−0.24770.56330.062*
C20.61625 (16)−0.0993 (2)0.52038 (13)0.0484 (5)
H20.6230−0.14810.47580.058*
C30.65447 (15)0.0336 (2)0.53320 (13)0.0477 (5)
C40.64007 (18)0.1008 (2)0.60023 (15)0.0565 (6)
H40.66370.19020.61100.068*
C50.59222 (18)0.0384 (3)0.65010 (15)0.0571 (6)
H50.58320.08560.69450.069*
C60.5107 (2)−0.1567 (4)0.69445 (17)0.0814 (9)
H6A0.5615−0.18700.73950.122*
H6B0.4723−0.23450.66990.122*
H6C0.4673−0.09240.71160.122*
C70.70733 (17)0.1044 (2)0.48149 (14)0.0547 (6)
H70.72580.19570.49280.066*
C80.73041 (18)0.0465 (3)0.41971 (15)0.0578 (6)
H80.7107−0.04470.40980.069*
C90.78346 (17)0.1085 (3)0.36470 (14)0.0545 (6)
C100.79432 (19)0.0317 (3)0.30061 (16)0.0616 (6)
H100.7700−0.05800.29440.074*
C110.84097 (18)0.0864 (3)0.24558 (15)0.0581 (6)
H110.84660.03350.20220.070*
C120.87921 (16)0.2176 (2)0.25382 (13)0.0486 (5)
C130.87119 (17)0.2968 (2)0.31965 (13)0.0503 (5)
C140.82272 (17)0.2423 (3)0.37394 (13)0.0541 (5)
H140.81610.29520.41710.065*
C150.9068 (2)0.5061 (3)0.39048 (17)0.0719 (8)
H15A0.94200.46130.43930.086*
H15B0.83760.51910.39220.086*
C160.9543 (3)0.6418 (4)0.3816 (2)0.1043 (13)
H16A0.95180.69980.42590.156*
H16B0.91890.68510.33320.156*
H16C1.02280.62760.38010.156*
C170.78797 (16)0.6487 (2)0.61343 (14)0.0476 (5)
C180.8387 (2)0.7012 (3)0.56113 (17)0.0652 (7)
H180.84280.65130.51630.078*
C190.8839 (2)0.8288 (3)0.5755 (2)0.0784 (9)
H190.91840.86370.53980.094*
C200.8792 (2)0.9043 (3)0.6399 (2)0.0763 (9)
C210.8292 (2)0.8499 (3)0.69306 (18)0.0749 (9)
H210.82650.89960.73830.090*
C220.78351 (19)0.7234 (3)0.67996 (14)0.0592 (6)
H220.74960.68840.71600.071*
C230.9251 (3)1.0473 (3)0.6528 (3)0.133 (2)
H23A0.97591.05600.62370.200*
H23B0.95431.06110.70840.200*
H23C0.87401.11510.63430.200*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S0.0666 (4)0.0422 (3)0.0802 (5)−0.0071 (3)0.0084 (3)0.0070 (3)
O10.0698 (10)0.0593 (9)0.0532 (9)−0.0040 (8)0.0257 (8)−0.0002 (7)
O20.0762 (11)0.0561 (9)0.0528 (9)−0.0154 (8)0.0230 (8)−0.0076 (7)
O30.0602 (12)0.0806 (14)0.156 (2)−0.0146 (10)0.0220 (13)0.0169 (14)
O40.0885 (14)0.0532 (11)0.133 (2)0.0007 (10)0.0020 (13)0.0301 (12)
O50.140 (2)0.0646 (12)0.0956 (17)−0.0186 (13)0.0156 (15)−0.0220 (12)
O60.0890 (16)0.0924 (16)0.0747 (14)−0.0218 (13)0.0189 (12)0.0171 (13)
N0.0447 (10)0.0609 (11)0.0485 (11)0.0068 (8)0.0112 (8)0.0105 (9)
C10.0492 (12)0.0417 (10)0.0614 (14)0.0022 (9)0.0090 (10)0.0038 (10)
C20.0493 (11)0.0485 (11)0.0476 (12)0.0041 (9)0.0124 (9)−0.0017 (9)
C30.0425 (11)0.0489 (11)0.0498 (12)0.0038 (9)0.0074 (9)0.0055 (9)
C40.0575 (13)0.0452 (11)0.0642 (15)0.0007 (10)0.0101 (11)−0.0056 (10)
C50.0561 (13)0.0622 (14)0.0523 (13)0.0067 (11)0.0121 (11)−0.0102 (11)
C60.0753 (18)0.109 (2)0.0651 (18)0.0012 (17)0.0274 (14)0.0299 (16)
C70.0548 (13)0.0484 (11)0.0597 (14)−0.0057 (10)0.0116 (11)0.0003 (10)
C80.0580 (14)0.0521 (12)0.0621 (15)−0.0083 (10)0.0120 (11)−0.0001 (11)
C90.0495 (12)0.0610 (13)0.0528 (13)−0.0070 (10)0.0125 (10)0.0046 (10)
C100.0634 (15)0.0551 (13)0.0673 (16)−0.0108 (11)0.0179 (12)−0.0025 (11)
C110.0614 (14)0.0585 (13)0.0563 (14)−0.0046 (11)0.0181 (11)−0.0078 (11)
C120.0448 (11)0.0556 (12)0.0451 (12)0.0015 (9)0.0105 (9)0.0028 (9)
C130.0499 (12)0.0525 (12)0.0463 (12)−0.0036 (9)0.0072 (9)−0.0002 (9)
C140.0550 (13)0.0624 (13)0.0453 (12)−0.0024 (10)0.0131 (10)−0.0032 (10)
C150.094 (2)0.0704 (16)0.0586 (15)−0.0280 (14)0.0324 (14)−0.0164 (12)
C160.163 (3)0.077 (2)0.098 (2)−0.052 (2)0.079 (2)−0.0346 (18)
C170.0463 (11)0.0381 (10)0.0570 (13)0.0030 (8)0.0101 (9)0.0011 (9)
C180.0755 (16)0.0488 (12)0.0830 (18)−0.0006 (11)0.0420 (14)−0.0084 (12)
C190.0653 (16)0.0535 (14)0.127 (3)−0.0044 (12)0.0430 (17)0.0067 (16)
C200.0515 (14)0.0437 (12)0.119 (3)0.0022 (11)−0.0074 (15)−0.0091 (15)
C210.0733 (17)0.0632 (15)0.0715 (18)0.0183 (14)−0.0146 (14)−0.0236 (14)
C220.0603 (14)0.0656 (14)0.0489 (13)0.0136 (11)0.0076 (11)0.0035 (11)
C230.083 (2)0.0527 (17)0.234 (6)−0.0123 (16)−0.021 (3)−0.023 (3)
Geometric parameters (Å, °) top
S—O51.420 (3)C9—C101.377 (4)
S—O41.427 (2)C9—C141.401 (3)
S—O31.469 (2)C10—C111.380 (3)
S—C171.760 (2)C10—H100.9300
O1—C121.353 (3)C11—C121.373 (3)
O1—H1O0.8200C11—H110.9300
O2—C131.356 (3)C12—C131.403 (3)
O2—C151.424 (3)C13—C141.385 (3)
O6—H6OA0.86 (3)C14—H140.9300
O6—H6OB0.85 (1)C15—C161.496 (4)
N—C51.330 (3)C15—H15A0.9700
N—C11.342 (3)C15—H15B0.9700
N—C61.471 (3)C16—H16A0.9600
C1—C21.360 (3)C16—H16B0.9600
C1—H10.9300C16—H16C0.9600
C2—C31.391 (3)C17—C181.371 (3)
C2—H20.9300C17—C221.377 (3)
C3—C41.389 (3)C18—C191.382 (4)
C3—C71.457 (3)C18—H180.9300
C4—C51.351 (4)C19—C201.351 (5)
C4—H40.9300C19—H190.9300
C5—H50.9300C20—C211.383 (5)
C6—H6A0.9600C20—C231.519 (4)
C6—H6B0.9600C21—C221.373 (4)
C6—H6C0.9600C21—H210.9300
C7—C81.315 (3)C22—H220.9300
C7—H70.9300C23—H23A0.9600
C8—C91.465 (3)C23—H23B0.9600
C8—H80.9300C23—H23C0.9600
O5—S—O4116.5 (2)C10—C11—H11119.4
O5—S—O3110.9 (2)O1—C12—C11123.1 (2)
O4—S—O3110.04 (15)O1—C12—C13117.6 (2)
O5—S—C17107.1 (1)C11—C12—C13119.3 (2)
O4—S—C17107.4 (1)O2—C13—C14125.4 (2)
O3—S—C17104.1 (1)O2—C13—C12115.2 (2)
C12—O1—H1O109.5C14—C13—C12119.3 (2)
C13—O2—C15116.5 (2)C13—C14—C9120.9 (2)
H6OA—O6—H6OB92 (1)C13—C14—H14119.6
C5—N—C1120.1 (2)C9—C14—H14119.6
C5—N—C6119.6 (2)O2—C15—C16107.3 (2)
C1—N—C6120.2 (2)O2—C15—H15A110.3
N—C1—C2120.7 (2)C16—C15—H15A110.3
N—C1—H1119.6O2—C15—H15B110.3
C2—C1—H1119.6C16—C15—H15B110.3
C1—C2—C3120.6 (2)H15A—C15—H15B108.5
C1—C2—H2119.7C15—C16—H16A109.5
C3—C2—H2119.7C15—C16—H16B109.5
C4—C3—C2116.4 (2)H16A—C16—H16B109.5
C4—C3—C7119.2 (2)C15—C16—H16C109.5
C2—C3—C7124.5 (2)H16A—C16—H16C109.5
C5—C4—C3121.0 (2)H16B—C16—H16C109.5
C5—C4—H4119.5C18—C17—C22119.4 (2)
C3—C4—H4119.5C18—C17—S120.46 (18)
N—C5—C4121.1 (2)C22—C17—S120.07 (19)
N—C5—H5119.5C17—C18—C19119.6 (3)
C4—C5—H5119.5C17—C18—H18120.2
N—C6—H6A109.5C19—C18—H18120.2
N—C6—H6B109.5C20—C19—C18121.8 (3)
H6A—C6—H6B109.5C20—C19—H19119.1
N—C6—H6C109.5C18—C19—H19119.1
H6A—C6—H6C109.5C19—C20—C21118.3 (2)
H6B—C6—H6C109.5C19—C20—C23121.1 (4)
C8—C7—C3123.7 (2)C21—C20—C23120.6 (3)
C8—C7—H7118.2C22—C21—C20121.0 (3)
C3—C7—H7118.2C22—C21—H21119.5
C7—C8—C9127.7 (2)C20—C21—H21119.5
C7—C8—H8116.1C21—C22—C17119.9 (3)
C9—C8—H8116.1C21—C22—H22120.1
C10—C9—C14118.7 (2)C17—C22—H22120.1
C10—C9—C8118.1 (2)C20—C23—H23A109.5
C14—C9—C8123.1 (2)C20—C23—H23B109.5
C9—C10—C11120.6 (2)H23A—C23—H23B109.5
C9—C10—H10119.7C20—C23—H23C109.5
C11—C10—H10119.7H23A—C23—H23C109.5
C12—C11—C10121.1 (2)H23B—C23—H23C109.5
C12—C11—H11119.4
C5—N—C1—C20.5 (3)O1—C12—C13—C14178.16 (19)
C6—N—C1—C2−177.3 (2)C11—C12—C13—C14−1.6 (3)
N—C1—C2—C30.5 (3)O2—C13—C14—C9−179.4 (2)
C1—C2—C3—C4−1.1 (3)C12—C13—C14—C91.2 (3)
C1—C2—C3—C7179.0 (2)C10—C9—C14—C130.3 (4)
C2—C3—C4—C50.6 (3)C8—C9—C14—C13−179.2 (2)
C7—C3—C4—C5−179.4 (2)C13—O2—C15—C16−178.7 (3)
C1—N—C5—C4−0.9 (3)O5—S—C17—C18−19.3 (2)
C6—N—C5—C4176.9 (2)O4—S—C17—C18106.6 (2)
C3—C4—C5—N0.3 (4)O3—S—C17—C18−136.8 (2)
C4—C3—C7—C8175.4 (2)O5—S—C17—C22158.9 (2)
C2—C3—C7—C8−4.7 (4)O4—S—C17—C22−75.3 (2)
C3—C7—C8—C9−179.7 (2)O3—S—C17—C2241.4 (2)
C7—C8—C9—C10−175.9 (2)C22—C17—C18—C19−0.6 (4)
C7—C8—C9—C143.5 (4)S—C17—C18—C19177.6 (2)
C14—C9—C10—C11−1.4 (4)C17—C18—C19—C20−0.2 (4)
C8—C9—C10—C11178.0 (2)C18—C19—C20—C211.2 (4)
C9—C10—C11—C121.1 (4)C18—C19—C20—C23−177.1 (3)
C10—C11—C12—O1−179.3 (2)C19—C20—C21—C22−1.3 (4)
C10—C11—C12—C130.4 (4)C23—C20—C21—C22176.9 (3)
C15—O2—C13—C141.6 (4)C20—C21—C22—C170.6 (4)
C15—O2—C13—C12−179.0 (2)C18—C17—C22—C210.4 (4)
O1—C12—C13—O2−1.3 (3)S—C17—C22—C21−177.75 (18)
C11—C12—C13—O2179.0 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O6i0.821.822.632 (3)170
O6—H6OB···O30.85 (1)2.36 (2)2.692 (3)104 (2)
O6—H6OA···O5ii0.86 (3)1.98 (3)2.832 (4)169 (3)
C4—H4···O40.932.533.426 (3)161
C5—H5···O1iii0.932.593.217 (3)125
Symmetry codes: (i) x+1/2, −y+1/2, z−1/2; (ii) −x+1, −y+1, −z+1; (iii) x−1/2, −y+1/2, z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O6i0.821.822.632 (3)170
O6—H6OB···O30.85 (1)2.36 (2)2.692 (3)104 (2)
O6—H6OA···O5ii0.86 (3)1.98 (3)2.832 (4)169 (3)
C4—H4···O40.932.533.426 (3)161
C5—H5···O1iii0.932.593.217 (3)125
Symmetry codes: (i) x+1/2, −y+1/2, z−1/2; (ii) −x+1, −y+1, −z+1; (iii) x−1/2, −y+1/2, z+1/2.
Acknowledgements top

SM and ASP thank Dr Babu Varghese, SAIF, IIT, Chennai, India, for the X-ray intensity data collection.

references
References top

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