Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807022076/ci2384sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807022076/ci2384Isup2.hkl |
CCDC reference: 651420
Key indicators
- Single-crystal X-ray study
- T = 297 K
- Mean (C-C) = 0.005 Å
- Disorder in main residue
- R factor = 0.072
- wR factor = 0.216
- Data-to-parameter ratio = 13.9
checkCIF/PLATON results
No syntax errors found
Alert level A PLAT432_ALERT_2_A Short Inter X...Y Contact I1A .. C12 .. 3.16 Ang.
Author Response: This may be due to the presence of disorder of the idione and bromine atoms. Otherwise I am at a loss to offer any other explanation. |
Alert level B PLAT432_ALERT_2_B Short Inter X...Y Contact I1B .. C15 .. 3.31 Ang.
Author Response: This may be due to the presence of disorder of the idione and bromine atoms. Otherwise I am at a loss to offer any other explanation. |
PLAT432_ALERT_2_B Short Inter X...Y Contact I1C .. C7 .. 3.36 Ang.
Author Response: This may be due to the presence of disorder of the idione and bromine atoms. Otherwise I am at a loss to offer any other explanation. |
PLAT432_ALERT_2_B Short Inter X...Y Contact I1C .. C14 .. 3.37 Ang.
Author Response: This may be due to the presence of disorder of the idione and bromine atoms. Otherwise I am at a loss to offer any other explanation. |
Alert level C PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ? PLAT077_ALERT_4_C Unitcell contains non-integer number of atoms .. ? PLAT301_ALERT_3_C Main Residue Disorder ......................... 5.00 Perc. PLAT431_ALERT_2_C Short Inter HL..A Contact I1A .. N1 .. 3.30 Ang. PLAT432_ALERT_2_C Short Inter X...Y Contact I1C .. C5 .. 3.41 Ang.
Author Response: This may be due to the presence of disorder of the idione and bromine atoms. Otherwise I am at a loss to offer any other explanation. |
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........ 1
Alert level G PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints ....... 1
1 ALERT level A = In general: serious problem 3 ALERT level B = Potentially serious problem 6 ALERT level C = Check and explain 1 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 6 ALERT type 2 Indicator that the structure model may be wrong or deficient 2 ALERT type 3 Indicator that the structure quality may be low 2 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
Silver(I) 4-bromobenzenesulfonate (0.20 g, 0.59 mmol) in hot methanol (50 ml) was added to a solution of 4-(4'-hydroxy-3'-methoxystyryl)-1-methylpyridinium iodide (0.22 g, 0.59 mmol) in hot methanol (40 ml). The mixture immediately yielded a yellow solid of silver iodide which was filtered off after stirring the mixture for 30 min. The resulting red solution was evaporated to yield a red-brown solid. Brown block-shaped single crystals of (I) were obtained by recrystallization from methanol-ethanol (1:1 v/v) at room temperature after several days.
The site occupancy factors for atoms Br1, I1A, I1B and I1C refined to 0.580 (3), 0.133 (2), 0.139 (2) and 0.148 (2), respectively. H atoms were placed in calculated positions, with O—H distance of 0.82 Å and C—H distances in the range 0.93–0.96 Å. The Uiso values were constrained to be 1.5Ueq of the carrier atom for hydroxyl and methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups. Owing to the large fraction of weak data at higher angles, the 2θ maximum was limited to 52°. The highest residual density peak is located 0.68 Å from atom C13 and the deepest hole is located 0.57 Å from atom Br1.
In recent years, much effort has been focused on the development of new materials with non-linear optical (NLO) properties (Patil et al., 2006; Shettigar et al., 2006). In our continuing systamatic study of NLO materials (Jindawong et al., 2005; Chantrapromma et al., 2005; Chantrapromma, Ruanwas, Fun et al., 2006; Chantrapromma, Jindawong & Fun, 2006; Chantrapromma, Ruanwas, Jindawong et al., 2006; Fun et al., 2006; Ruanwas et al., 2007; Chantrapromma et al., 2007), the title compound, (I), was synthesized and its crystal structure is reported here. Compound (I) crystallizes in a centrosymmetric space group and this precludes the presence of second-order NLO properties.
The refinement of (I) revealed the composition to be C15H16NO2+.0.58Br-.0.42I- (Fig. 1), i.e. with fractional occupancy of the halide ions. Moreover, the iodide ion is disordered over three sites (I1A, I1B and I1C in Fig. 1). The cation exists in an E configuration with respect to the C7═C8 double bond [1.330 (6) Å], with the torsion angle C6–C7–C8–C9 being -178.8 (3)°. The bond lengths and angles (Table 1) have normal values (Allen et al., 1987) and comparable to those in related structures (Jindawong et al., 2005; Chantrapromma et al., 2005; Chantrapromma, Ruanwas, Fun et al., 2006; Chantrapromma, Jindawong & Fun, 2006; Chantrapromma, Ruanwas, Jindawong et al., 2006; Ruanwas et al., 2007; Chantrapromma et al., 2007). The cation is essentially planar, the dihedral angle between the pyridinium and benzene rings is 2.59 (18)°. The C14—O2—C4—C5 torsion angle of -5.6 (6)° shows that the methoxy group is slightly twisted out of the benzene ring plane.
Intermolecular O—H···Br hydrogen bonds and weak C—H···O interactions are observed in the crystal structure of (I) (Table 1). The cations are linked together in a head-to-tail manner into zigzag chains along the b axis through weak C—H···O interactions, and these chains are cross-linked by O—H···Br, O—H···I (H···I = 1.97–2.48 Å) and C—H···I (H···I = 2.47–2.91 Å) interactions forming a three-dimensional network (Fig. 2). The centroid-centroid distance between the N1/C9–C13 ring at (x, y, z) and the C1–C6 benzene ring at (2 - x, -y, -1 - z) is 3.518 (2) Å, indicating π-π interactions. A C12···I1A(-x, 1 - y, 1 - z) short contact [3.156 (7) Å] is observed in the crystal structure.
For bond-length data, see: Allen et al. (1987). For related structures, see: Jindawong et al. (2005); Chantrapromma et al. (2005); Chantrapromma, Ruanwas, Fun et al. (2006); Chantrapromma, Jindawong & Fun (2006); Chantrapromma, Ruanwas, Jindawong et al. (2006); Fun et al. (2006); Ruanwas et al. (2007); Chantrapromma et al. (2007); Patil et al. (2006); Shettigar et al. (2006).
Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).
C15H16NO2+·0.58Br−·0.42I− | F(000) = 686.2 |
Mr = 341.93 | Dx = 1.554 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 2857 reflections |
a = 8.9627 (13) Å | θ = 2.0–26.0° |
b = 20.721 (3) Å | µ = 2.55 mm−1 |
c = 8.0865 (12) Å | T = 297 K |
β = 103.304 (2)° | Block, brown |
V = 1461.5 (4) Å3 | 0.51 × 0.25 × 0.21 mm |
Z = 4 |
Siemens SMART CCD area-detector diffractometer | 2857 independent reflections |
Radiation source: fine-focus sealed tube | 2417 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
Detector resolution: 8.33 pixels mm-1 | θmax = 26.0°, θmin = 2.0° |
ω scans | h = −9→11 |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | k = −25→19 |
Tmin = 0.458, Tmax = 0.583 | l = −9→9 |
7691 measured reflections |
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)] = 0.072 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.216 | H-atom parameters constrained |
S = 1.08 | w = 1/[σ2(Fo2) + (0.1083P)2 + 1.625P] where P = (Fo2 + 2Fc2)/3 |
2857 reflections | (Δ/σ)max = 0.001 |
206 parameters | Δρmax = 0.31 e Å−3 |
1 restraint | Δρmin = −0.72 e Å−3 |
C15H16NO2+·0.58Br−·0.42I− | V = 1461.5 (4) Å3 |
Mr = 341.93 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.9627 (13) Å | µ = 2.55 mm−1 |
b = 20.721 (3) Å | T = 297 K |
c = 8.0865 (12) Å | 0.51 × 0.25 × 0.21 mm |
β = 103.304 (2)° |
Siemens SMART CCD area-detector diffractometer | 2857 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2417 reflections with I > 2σ(I) |
Tmin = 0.458, Tmax = 0.583 | Rint = 0.024 |
7691 measured reflections |
R[F2 > 2σ(F2)] = 0.072 | 1 restraint |
wR(F2) = 0.216 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.31 e Å−3 |
2857 reflections | Δρmin = −0.72 e Å−3 |
206 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
I1A | 0.6170 (7) | 0.6319 (3) | 0.7668 (8) | 0.155 (3) | 0.133 (2) |
I1B | 0.7345 (9) | 0.6386 (3) | 0.5754 (7) | 0.181 (3) | 0.139 (2) |
I1C | 0.8589 (6) | 0.6382 (3) | 0.8253 (8) | 0.169 (3) | 0.148 (2) |
Br1 | 0.72947 (12) | 0.63747 (4) | 0.73911 (13) | 0.0761 (5) | 0.580 (3) |
O1 | 0.3913 (3) | 0.68060 (15) | 0.4999 (4) | 0.0709 (9) | |
H1O1 | 0.4627 | 0.6642 | 0.5691 | 0.106* | |
O2 | 0.1697 (3) | 0.71700 (14) | 0.2545 (3) | 0.0596 (7) | |
N1 | −0.4889 (3) | 0.35571 (15) | −0.1165 (4) | 0.0504 (7) | |
C1 | 0.1803 (5) | 0.5284 (2) | 0.4242 (5) | 0.0553 (9) | |
H1 | 0.1863 | 0.4863 | 0.4651 | 0.066* | |
C2 | 0.2924 (5) | 0.5724 (2) | 0.4963 (5) | 0.0570 (9) | |
H2 | 0.3728 | 0.5597 | 0.5850 | 0.068* | |
C3 | 0.2858 (4) | 0.63491 (19) | 0.4377 (5) | 0.0524 (9) | |
C4 | 0.1610 (4) | 0.65448 (18) | 0.3036 (4) | 0.0477 (8) | |
C5 | 0.0524 (4) | 0.61018 (19) | 0.2341 (4) | 0.0491 (8) | |
H5 | −0.0286 | 0.6228 | 0.1460 | 0.059* | |
C6 | 0.0588 (4) | 0.54602 (19) | 0.2915 (4) | 0.0495 (8) | |
C7 | −0.0532 (4) | 0.4967 (2) | 0.2190 (5) | 0.0537 (9) | |
H7 | −0.0399 | 0.4564 | 0.2712 | 0.064* | |
C8 | −0.1721 (4) | 0.50257 (19) | 0.0869 (5) | 0.0520 (9) | |
H8 | −0.1889 | 0.5426 | 0.0340 | 0.062* | |
C9 | −0.2779 (4) | 0.45054 (18) | 0.0196 (4) | 0.0480 (8) | |
C10 | −0.4000 (4) | 0.46270 (19) | −0.1185 (5) | 0.0534 (9) | |
H10 | −0.4120 | 0.5036 | −0.1670 | 0.064* | |
C11 | −0.5017 (4) | 0.4153 (2) | −0.1830 (5) | 0.0549 (9) | |
H11 | −0.5821 | 0.4245 | −0.2754 | 0.066* | |
C12 | −0.3730 (4) | 0.3415 (2) | 0.0155 (5) | 0.0555 (9) | |
H12 | −0.3645 | 0.3001 | 0.0610 | 0.067* | |
C13 | −0.2664 (4) | 0.3878 (2) | 0.0845 (5) | 0.0542 (9) | |
H13 | −0.1858 | 0.3771 | 0.1752 | 0.065* | |
C14 | 0.0455 (5) | 0.7404 (2) | 0.1262 (6) | 0.0681 (11) | |
H14A | 0.0667 | 0.7838 | 0.0969 | 0.102* | |
H14B | −0.0467 | 0.7398 | 0.1675 | 0.102* | |
H14C | 0.0325 | 0.7134 | 0.0274 | 0.102* | |
C15 | −0.6045 (6) | 0.3056 (2) | −0.1849 (7) | 0.0761 (13) | |
H15A | −0.5549 | 0.2693 | −0.2228 | 0.114* | |
H15B | −0.6793 | 0.3231 | −0.2788 | 0.114* | |
H15C | −0.6543 | 0.2921 | −0.0976 | 0.114* |
U11 | U22 | U33 | U12 | U13 | U23 | |
I1A | 0.109 (4) | 0.178 (5) | 0.180 (5) | 0.002 (3) | 0.034 (3) | 0.028 (4) |
I1B | 0.219 (7) | 0.194 (6) | 0.120 (4) | 0.030 (4) | 0.020 (4) | 0.007 (3) |
I1C | 0.126 (4) | 0.189 (6) | 0.171 (5) | −0.004 (3) | −0.010 (3) | 0.020 (3) |
Br1 | 0.0675 (7) | 0.0599 (5) | 0.0894 (7) | 0.0047 (4) | −0.0053 (4) | 0.0109 (4) |
O1 | 0.0550 (17) | 0.0665 (18) | 0.078 (2) | −0.0038 (14) | −0.0127 (14) | −0.0072 (15) |
O2 | 0.0544 (15) | 0.0577 (16) | 0.0601 (16) | −0.0027 (12) | −0.0003 (12) | 0.0014 (12) |
N1 | 0.0451 (16) | 0.0563 (18) | 0.0500 (17) | −0.0027 (13) | 0.0113 (13) | −0.0026 (13) |
C1 | 0.062 (2) | 0.058 (2) | 0.0466 (19) | −0.0003 (18) | 0.0145 (16) | 0.0046 (16) |
C2 | 0.055 (2) | 0.066 (2) | 0.0457 (19) | 0.0013 (18) | 0.0042 (16) | 0.0014 (17) |
C3 | 0.0466 (19) | 0.061 (2) | 0.0462 (19) | −0.0006 (16) | 0.0038 (15) | −0.0058 (16) |
C4 | 0.0447 (18) | 0.055 (2) | 0.0432 (18) | 0.0010 (15) | 0.0092 (14) | −0.0044 (15) |
C5 | 0.0424 (18) | 0.064 (2) | 0.0412 (17) | 0.0029 (16) | 0.0100 (14) | −0.0041 (15) |
C6 | 0.0476 (18) | 0.059 (2) | 0.0452 (18) | −0.0052 (16) | 0.0183 (15) | −0.0057 (15) |
C7 | 0.053 (2) | 0.059 (2) | 0.053 (2) | −0.0001 (17) | 0.0202 (16) | 0.0015 (16) |
C8 | 0.053 (2) | 0.055 (2) | 0.051 (2) | −0.0003 (16) | 0.0182 (16) | 0.0003 (16) |
C9 | 0.0468 (18) | 0.055 (2) | 0.0464 (18) | 0.0003 (15) | 0.0185 (14) | −0.0044 (15) |
C10 | 0.056 (2) | 0.053 (2) | 0.053 (2) | 0.0045 (17) | 0.0145 (16) | 0.0008 (16) |
C11 | 0.0475 (19) | 0.066 (2) | 0.050 (2) | 0.0035 (17) | 0.0082 (15) | −0.0028 (17) |
C12 | 0.054 (2) | 0.057 (2) | 0.057 (2) | −0.0007 (17) | 0.0155 (17) | 0.0038 (17) |
C13 | 0.0486 (19) | 0.065 (2) | 0.048 (2) | 0.0043 (17) | 0.0080 (15) | 0.0018 (17) |
C14 | 0.066 (3) | 0.062 (2) | 0.068 (3) | 0.003 (2) | −0.001 (2) | 0.006 (2) |
C15 | 0.072 (3) | 0.074 (3) | 0.076 (3) | −0.023 (2) | 0.003 (2) | −0.004 (2) |
O1—C3 | 1.351 (5) | C7—H7 | 0.93 |
O1—H1O1 | 0.82 | C8—C9 | 1.456 (5) |
O2—C4 | 1.363 (5) | C8—H8 | 0.93 |
O2—C14 | 1.421 (5) | C9—C10 | 1.395 (5) |
N1—C12 | 1.340 (5) | C9—C13 | 1.397 (5) |
N1—C11 | 1.341 (5) | C10—C11 | 1.359 (6) |
N1—C15 | 1.480 (5) | C10—H10 | 0.93 |
C1—C2 | 1.383 (6) | C11—H11 | 0.93 |
C1—C6 | 1.390 (5) | C12—C13 | 1.378 (6) |
C1—H1 | 0.93 | C12—H12 | 0.93 |
C2—C3 | 1.375 (6) | C13—H13 | 0.93 |
C2—H2 | 0.93 | C14—H14A | 0.96 |
C3—C4 | 1.426 (5) | C14—H14B | 0.96 |
C4—C5 | 1.362 (5) | C14—H14C | 0.96 |
C5—C6 | 1.405 (6) | C15—H15A | 0.96 |
C5—H5 | 0.93 | C15—H15B | 0.96 |
C6—C7 | 1.458 (5) | C15—H15C | 0.96 |
C7—C8 | 1.330 (6) | ||
C3—O1—H1O1 | 109.5 | C9—C8—H8 | 117.8 |
C4—O2—C14 | 116.7 (3) | C10—C9—C13 | 116.4 (3) |
C12—N1—C11 | 120.0 (3) | C10—C9—C8 | 119.3 (3) |
C12—N1—C15 | 119.5 (4) | C13—C9—C8 | 124.3 (3) |
C11—N1—C15 | 120.5 (4) | C11—C10—C9 | 120.7 (4) |
C2—C1—C6 | 121.0 (4) | C11—C10—H10 | 119.7 |
C2—C1—H1 | 119.5 | C9—C10—H10 | 119.7 |
C6—C1—H1 | 119.5 | N1—C11—C10 | 121.6 (4) |
C3—C2—C1 | 120.4 (4) | N1—C11—H11 | 119.2 |
C3—C2—H2 | 119.8 | C10—C11—H11 | 119.2 |
C1—C2—H2 | 119.8 | N1—C12—C13 | 120.6 (4) |
O1—C3—C2 | 124.1 (4) | N1—C12—H12 | 119.7 |
O1—C3—C4 | 116.3 (3) | C13—C12—H12 | 119.7 |
C2—C3—C4 | 119.6 (3) | C12—C13—C9 | 120.7 (4) |
C5—C4—O2 | 127.1 (3) | C12—C13—H13 | 119.6 |
C5—C4—C3 | 118.9 (4) | C9—C13—H13 | 119.6 |
O2—C4—C3 | 113.9 (3) | O2—C14—H14A | 109.5 |
C4—C5—C6 | 122.0 (3) | O2—C14—H14B | 109.5 |
C4—C5—H5 | 119.0 | H14A—C14—H14B | 109.5 |
C6—C5—H5 | 119.0 | O2—C14—H14C | 109.5 |
C1—C6—C5 | 118.0 (3) | H14A—C14—H14C | 109.5 |
C1—C6—C7 | 118.1 (4) | H14B—C14—H14C | 109.5 |
C5—C6—C7 | 123.9 (3) | N1—C15—H15A | 109.5 |
C8—C7—C6 | 127.5 (4) | N1—C15—H15B | 109.5 |
C8—C7—H7 | 116.2 | H15A—C15—H15B | 109.5 |
C6—C7—H7 | 116.2 | N1—C15—H15C | 109.5 |
C7—C8—C9 | 124.4 (4) | H15A—C15—H15C | 109.5 |
C7—C8—H8 | 117.8 | H15B—C15—H15C | 109.5 |
C6—C1—C2—C3 | 0.0 (6) | C1—C6—C7—C8 | −176.2 (4) |
C1—C2—C3—O1 | −179.3 (4) | C5—C6—C7—C8 | 3.1 (6) |
C1—C2—C3—C4 | 1.0 (6) | C6—C7—C8—C9 | 178.8 (3) |
C14—O2—C4—C5 | 5.7 (6) | C7—C8—C9—C10 | 179.2 (3) |
C14—O2—C4—C3 | −177.4 (3) | C7—C8—C9—C13 | −0.7 (6) |
O1—C3—C4—C5 | 179.0 (3) | C13—C9—C10—C11 | 0.7 (5) |
C2—C3—C4—C5 | −1.3 (5) | C8—C9—C10—C11 | −179.2 (3) |
O1—C3—C4—O2 | 1.8 (5) | C12—N1—C11—C10 | −0.7 (6) |
C2—C3—C4—O2 | −178.5 (3) | C15—N1—C11—C10 | 177.7 (4) |
O2—C4—C5—C6 | 177.4 (3) | C9—C10—C11—N1 | 0.2 (6) |
C3—C4—C5—C6 | 0.5 (5) | C11—N1—C12—C13 | 0.1 (5) |
C2—C1—C6—C5 | −0.7 (5) | C15—N1—C12—C13 | −178.2 (4) |
C2—C1—C6—C7 | 178.6 (3) | N1—C12—C13—C9 | 0.8 (6) |
C4—C5—C6—C1 | 0.4 (5) | C10—C9—C13—C12 | −1.2 (5) |
C4—C5—C6—C7 | −178.8 (3) | C8—C9—C13—C12 | 178.7 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O1···Br1 | 0.82 | 2.53 | 3.321 (3) | 162 |
C12—H12···O1i | 0.93 | 2.52 | 3.338 (5) | 146 |
Symmetry code: (i) −x, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C15H16NO2+·0.58Br−·0.42I− |
Mr | 341.93 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 297 |
a, b, c (Å) | 8.9627 (13), 20.721 (3), 8.0865 (12) |
β (°) | 103.304 (2) |
V (Å3) | 1461.5 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 2.55 |
Crystal size (mm) | 0.51 × 0.25 × 0.21 |
Data collection | |
Diffractometer | Siemens SMART CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.458, 0.583 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7691, 2857, 2417 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.072, 0.216, 1.08 |
No. of reflections | 2857 |
No. of parameters | 206 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.31, −0.72 |
Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SAINT, SHELXTL (Sheldrick, 1997), SHELXTL and PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O1···Br1 | 0.82 | 2.53 | 3.321 (3) | 162 |
C12—H12···O1i | 0.93 | 2.52 | 3.338 (5) | 146 |
Symmetry code: (i) −x, y−1/2, −z+1/2. |
In recent years, much effort has been focused on the development of new materials with non-linear optical (NLO) properties (Patil et al., 2006; Shettigar et al., 2006). In our continuing systamatic study of NLO materials (Jindawong et al., 2005; Chantrapromma et al., 2005; Chantrapromma, Ruanwas, Fun et al., 2006; Chantrapromma, Jindawong & Fun, 2006; Chantrapromma, Ruanwas, Jindawong et al., 2006; Fun et al., 2006; Ruanwas et al., 2007; Chantrapromma et al., 2007), the title compound, (I), was synthesized and its crystal structure is reported here. Compound (I) crystallizes in a centrosymmetric space group and this precludes the presence of second-order NLO properties.
The refinement of (I) revealed the composition to be C15H16NO2+.0.58Br-.0.42I- (Fig. 1), i.e. with fractional occupancy of the halide ions. Moreover, the iodide ion is disordered over three sites (I1A, I1B and I1C in Fig. 1). The cation exists in an E configuration with respect to the C7═C8 double bond [1.330 (6) Å], with the torsion angle C6–C7–C8–C9 being -178.8 (3)°. The bond lengths and angles (Table 1) have normal values (Allen et al., 1987) and comparable to those in related structures (Jindawong et al., 2005; Chantrapromma et al., 2005; Chantrapromma, Ruanwas, Fun et al., 2006; Chantrapromma, Jindawong & Fun, 2006; Chantrapromma, Ruanwas, Jindawong et al., 2006; Ruanwas et al., 2007; Chantrapromma et al., 2007). The cation is essentially planar, the dihedral angle between the pyridinium and benzene rings is 2.59 (18)°. The C14—O2—C4—C5 torsion angle of -5.6 (6)° shows that the methoxy group is slightly twisted out of the benzene ring plane.
Intermolecular O—H···Br hydrogen bonds and weak C—H···O interactions are observed in the crystal structure of (I) (Table 1). The cations are linked together in a head-to-tail manner into zigzag chains along the b axis through weak C—H···O interactions, and these chains are cross-linked by O—H···Br, O—H···I (H···I = 1.97–2.48 Å) and C—H···I (H···I = 2.47–2.91 Å) interactions forming a three-dimensional network (Fig. 2). The centroid-centroid distance between the N1/C9–C13 ring at (x, y, z) and the C1–C6 benzene ring at (2 - x, -y, -1 - z) is 3.518 (2) Å, indicating π-π interactions. A C12···I1A(-x, 1 - y, 1 - z) short contact [3.156 (7) Å] is observed in the crystal structure.