| Literature DB >> 28932424 |
Tuhin Khan1, Navneet Mishra1, Darshan S Mhatre1, Anindya Datta1.
Abstract
1-(2-Hy-droxy-benz-yl)-2-(2-hy-droxy-phen-yl)-1H-benzimidazol-3-ium chloride, C20H17N2O2+·Cl-, was prepared by reaction of salicyl-aldehyde with o-phenyl-enedi-amine in the presence of tri-methyl-silyl chloride acting as a source of HCl. As a result of steric hindrance, the cation in the crystal is far from planar: the benzimidazole ring system makes dihedral angles of 55.49 (9) and 81.36 (8)° with the planes of the phenolic groups. The crystal packing is dominated by O-H⋯Cl and N-H⋯Cl hydrogen bonds, which link the cations and anions into four-membered rings and then into chains along [100]. The title compound exhibits two transitions in the UV region, which are revealed in the solid state and solution spectra as an absorption maximum at 280 nm and a shoulder at 320 nm. According to the results of TD-DFT calculation, both transitions have a π-π* nature and the mol-ecular orbitals involved in these transitions are mostly localized on the benzimidazole ring system and on the phenyl ring attached to it at the 2-position.Entities:
Keywords: DFT calculations; Hirshfeld surface analysis; UV spectra; benzimidazole; crystal structure; hydrogen bonding
Year: 2017 PMID: 28932424 PMCID: PMC5598836 DOI: 10.1107/S205698901700977X
Source DB: PubMed Journal: Acta Crystallogr E Crystallogr Commun
Figure 1ORTEP diagram of the title compound with displacement ellipsoids drawn at the 50% probability level.
Hydrogen-bond geometry (Å, °)
|
|
| H⋯ |
|
|
|---|---|---|---|---|
| O1—H1⋯Cl1i | 0.84 | 2.24 | 3.066 (2) | 169 |
| O2—H2⋯Cl1 | 0.84 | 2.23 | 3.071 (1) | 177 |
| N2—H2 | 0.88 | 2.23 | 3.084 (2) | 162 |
| C16—H16⋯O1iii | 0.95 | 2.57 | 3.253 (2) | 129 |
| C19—H19⋯Cl1 | 0.95 | 2.93 | 3.646 (2) | 134 |
| C7—H7 | 0.99 | 2.77 | 3.500 (2) | 131 |
Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .
Figure 2Packing diagram highlighting the hydrogen-bonding interactions.
Figure 3Hirshfeld surface of the ionic pair mapped with normalized contact distances (d norm) indicated by red spots. Positions of close contacts are highlighted by red arrows.
Comparison of notable bond lengths and torsion angles (Å, °)
| Crystal | DFT optimized | |
|---|---|---|
| C20—O2 | 1.356 (2) | 1.315 |
| C20—C19 | 1.391 (3) | 1.413 |
| C14—N2 | 1.337 (2) | 1.356 |
| C14—N1 | 1.344 (2) | 1.349 |
| ∠ C16—C15—C14—N1 | 123.4 (2) | 137.99 |
| ∠ C20—C15—C14—N2 | 125.5 (2) | 132.45 |
Figure 4(a) Peak-normalized absorption spectrum of the compound in methanolic solution (blue), Kubelka–Munk (KM) transformed diffuse reflectance solid-state spectrum (red) and TD–DFT calculated transitions (green). (b) Molecular orbital energy levels and the relevant Kohn–Sham orbitals.
Prominent electronic transitions obtained from TD–DFT calculation
| Wavelength | Oscillator strength | Transition |
|---|---|---|
| 356 nm | 0.088 | LUMO←HOMO-3 (98%) |
| 277 nm | 0.2827 | LUMO←HOMO-5 (96%) |
| 253 nm | 0.0537 | LUMO+2←HOMO-3 (78%) |
| LUMO+3←HOMO-3 (12%) |
Experimental details
| Crystal data | |
| Chemical formula | C20H17N2O2 +·Cl− |
|
| 352.80 |
| Crystal system, space group | Triclinic, |
| Temperature (K) | 150 |
|
| 9.8002 (4), 10.6791 (5), 10.6986 (4) |
| α, β, γ (°) | 111.364 (4), 102.346 (3), 111.311 (4) |
|
| 890.75 (7) |
|
| 2 |
| Radiation type | Mo |
| μ (mm−1) | 0.23 |
| Crystal size (mm) | 0.19 × 0.18 × 0.12 |
| Data collection | |
| Diffractometer | Rigaku Saturn 724 |
| Absorption correction | Multi-scan ( |
|
| 0.657, 1.000 |
| No. of measured, independent and observed [ | 8813, 3114, 2654 |
|
| 0.033 |
| (sin θ/λ)max (Å−1) | 0.595 |
| Refinement | |
|
| 0.039, 0.105, 1.04 |
| No. of reflections | 3114 |
| No. of parameters | 228 |
| H-atom treatment | H-atom parameters constrained |
| Δρmax, Δρmin (e Å−3) | 0.25, −0.21 |
Computer programs: CrysAlis PRO (Rigaku Oxford Diffraction, 2015 ▸), SHELXT (Sheldrick, 2015a ▸), SHELXL2014 (Sheldrick, 2015b ▸) and OLEX2 (Dolomanov et al., 2009 ▸).
| C20H17N2O2+·Cl− | |
| Triclinic, | |
| Mo | |
| Cell parameters from 5921 reflections | |
| θ = 2.3–31.1° | |
| α = 111.364 (4)° | µ = 0.23 mm−1 |
| β = 102.346 (3)° | |
| γ = 111.311 (4)° | Plate, colourless |
| 0.19 × 0.18 × 0.12 mm |
| Rigaku Saturn 724 diffractometer | 3114 independent reflections |
| Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source | 2654 reflections with |
| Graphite monochromator | |
| ω scans | θmax = 25.0°, θmin = 2.3° |
| Absorption correction: multi-scan (CrysAlis PRO; Rigaku Oxford Diffraction, 2015) | |
| 8813 measured reflections |
| Refinement on | 0 restraints |
| Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
| H-atom parameters constrained | |
| (Δ/σ)max = 0.001 | |
| 3114 reflections | Δρmax = 0.25 e Å−3 |
| 228 parameters | Δρmin = −0.21 e Å−3 |
| 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. 1. Fixed Uiso At 1.2 times of: All C(H) groups, All C(H,H) groups, All N(H) groups At 1.5 times of: All O(H) groups 2.a Secondary CH2 refined with riding coordinates: C7(H7A,H7B) 2.b Aromatic/amide H refined with riding coordinates: N2(H2A), C2(H2B), C3(H3), C4(H4), C5(H5), C9(H9), C10(H10), C11(H11), C12(H12), C16(H16), C17(H17), C18(H18), C19(H19) 2.c Idealised tetrahedral OH refined as rotating group: O1(H1), O2(H2) |
| Cl1 | −0.06343 (6) | 0.67366 (6) | 0.86942 (5) | 0.04152 (17) | |
| O1 | 0.57838 (18) | 0.45573 (18) | 0.75661 (16) | 0.0457 (4) | |
| H1 | 0.6774 | 0.5046 | 0.7816 | 0.069* | |
| O2 | 0.07420 (16) | 0.49890 (14) | 0.68652 (15) | 0.0381 (3) | |
| H2 | 0.0365 | 0.5481 | 0.7349 | 0.057* | |
| N1 | 0.23361 (18) | 0.29524 (16) | 0.60618 (15) | 0.0302 (3) | |
| N2 | 0.18508 (19) | 0.27540 (17) | 0.38883 (16) | 0.0337 (4) | |
| H2A | 0.1727 | 0.2994 | 0.3183 | 0.040* | |
| C7 | 0.2833 (2) | 0.3651 (2) | 0.76670 (19) | 0.0325 (4) | |
| H7A | 0.1877 | 0.3293 | 0.7888 | 0.039* | |
| H7B | 0.3331 | 0.4783 | 0.8101 | 0.039* | |
| C1 | 0.5475 (2) | 0.3725 (2) | 0.8279 (2) | 0.0355 (4) | |
| C2 | 0.6572 (3) | 0.3358 (2) | 0.8901 (2) | 0.0428 (5) | |
| H2B | 0.7577 | 0.3671 | 0.8826 | 0.051* | |
| C3 | 0.6179 (3) | 0.2535 (2) | 0.9626 (2) | 0.0467 (5) | |
| H3 | 0.6913 | 0.2262 | 1.0033 | 0.056* | |
| C4 | 0.4745 (3) | 0.2105 (2) | 0.9770 (2) | 0.0467 (5) | |
| H4 | 0.4506 | 0.1571 | 1.0303 | 0.056* | |
| C5 | 0.3645 (3) | 0.2453 (2) | 0.9129 (2) | 0.0400 (5) | |
| H5 | 0.2647 | 0.2148 | 0.9217 | 0.048* | |
| C6 | 0.3999 (2) | 0.3248 (2) | 0.83576 (18) | 0.0325 (4) | |
| C8 | 0.1953 (2) | 0.1454 (2) | 0.50925 (19) | 0.0321 (4) | |
| C9 | 0.1862 (2) | 0.0217 (2) | 0.5291 (2) | 0.0380 (5) | |
| H9 | 0.2058 | 0.0277 | 0.6225 | 0.046* | |
| C10 | 0.1472 (3) | −0.1105 (2) | 0.4064 (2) | 0.0428 (5) | |
| H10 | 0.1417 | −0.1968 | 0.4163 | 0.051* | |
| C11 | 0.1156 (3) | −0.1214 (2) | 0.2682 (2) | 0.0422 (5) | |
| H11 | 0.0886 | −0.2150 | 0.1867 | 0.051* | |
| C12 | 0.1225 (2) | −0.0002 (2) | 0.2470 (2) | 0.0384 (5) | |
| H12 | 0.0995 | −0.0078 | 0.1528 | 0.046* | |
| C13 | 0.1650 (2) | 0.1346 (2) | 0.3711 (2) | 0.0333 (4) | |
| C14 | 0.2263 (2) | 0.3700 (2) | 0.52966 (19) | 0.0309 (4) | |
| C15 | 0.2661 (2) | 0.5309 (2) | 0.58492 (19) | 0.0319 (4) | |
| C16 | 0.3810 (2) | 0.6224 (2) | 0.5524 (2) | 0.0385 (5) | |
| H16 | 0.4303 | 0.5785 | 0.4957 | 0.046* | |
| C17 | 0.4234 (3) | 0.7744 (2) | 0.6010 (2) | 0.0428 (5) | |
| H17 | 0.5025 | 0.8362 | 0.5796 | 0.051* | |
| C18 | 0.3493 (3) | 0.8366 (2) | 0.6819 (2) | 0.0402 (5) | |
| H18 | 0.3796 | 0.9423 | 0.7175 | 0.048* | |
| C19 | 0.2325 (2) | 0.7481 (2) | 0.7116 (2) | 0.0356 (4) | |
| H19 | 0.1812 | 0.7922 | 0.7651 | 0.043* | |
| C20 | 0.1895 (2) | 0.5940 (2) | 0.66327 (19) | 0.0314 (4) |
| Cl1 | 0.0437 (3) | 0.0520 (3) | 0.0327 (3) | 0.0275 (3) | 0.0155 (2) | 0.0196 (2) |
| O1 | 0.0415 (9) | 0.0639 (10) | 0.0441 (8) | 0.0290 (8) | 0.0202 (7) | 0.0329 (8) |
| O2 | 0.0398 (8) | 0.0354 (7) | 0.0450 (8) | 0.0232 (7) | 0.0205 (7) | 0.0183 (6) |
| N1 | 0.0339 (9) | 0.0275 (8) | 0.0257 (8) | 0.0183 (7) | 0.0072 (7) | 0.0089 (6) |
| N2 | 0.0394 (10) | 0.0352 (8) | 0.0272 (8) | 0.0214 (8) | 0.0109 (7) | 0.0139 (7) |
| C7 | 0.0370 (11) | 0.0326 (10) | 0.0250 (9) | 0.0199 (9) | 0.0095 (8) | 0.0099 (8) |
| C1 | 0.0420 (12) | 0.0379 (10) | 0.0254 (9) | 0.0232 (9) | 0.0114 (9) | 0.0117 (8) |
| C2 | 0.0449 (13) | 0.0488 (12) | 0.0330 (11) | 0.0305 (11) | 0.0106 (10) | 0.0131 (9) |
| C3 | 0.0574 (15) | 0.0436 (12) | 0.0340 (11) | 0.0329 (11) | 0.0055 (10) | 0.0127 (10) |
| C4 | 0.0639 (16) | 0.0346 (11) | 0.0321 (11) | 0.0226 (11) | 0.0068 (11) | 0.0154 (9) |
| C5 | 0.0452 (13) | 0.0335 (10) | 0.0313 (10) | 0.0161 (9) | 0.0094 (9) | 0.0126 (9) |
| C6 | 0.0401 (11) | 0.0295 (9) | 0.0217 (9) | 0.0192 (9) | 0.0073 (8) | 0.0070 (8) |
| C8 | 0.0312 (11) | 0.0289 (9) | 0.0292 (10) | 0.0172 (8) | 0.0066 (8) | 0.0079 (8) |
| C9 | 0.0400 (12) | 0.0343 (10) | 0.0343 (10) | 0.0206 (9) | 0.0074 (9) | 0.0131 (9) |
| C10 | 0.0435 (13) | 0.0312 (10) | 0.0451 (12) | 0.0222 (10) | 0.0078 (10) | 0.0117 (9) |
| C11 | 0.0391 (12) | 0.0329 (10) | 0.0366 (11) | 0.0190 (9) | 0.0069 (9) | 0.0027 (9) |
| C12 | 0.0364 (12) | 0.0385 (11) | 0.0278 (10) | 0.0192 (9) | 0.0064 (9) | 0.0067 (8) |
| C13 | 0.0291 (10) | 0.0337 (10) | 0.0317 (10) | 0.0178 (9) | 0.0079 (8) | 0.0106 (8) |
| C14 | 0.0293 (10) | 0.0332 (10) | 0.0291 (9) | 0.0187 (8) | 0.0084 (8) | 0.0123 (8) |
| C15 | 0.0339 (11) | 0.0327 (10) | 0.0278 (9) | 0.0195 (9) | 0.0072 (8) | 0.0130 (8) |
| C16 | 0.0437 (12) | 0.0436 (11) | 0.0380 (11) | 0.0276 (10) | 0.0184 (10) | 0.0216 (9) |
| C17 | 0.0440 (13) | 0.0415 (11) | 0.0499 (12) | 0.0220 (10) | 0.0189 (11) | 0.0274 (10) |
| C18 | 0.0467 (13) | 0.0311 (10) | 0.0404 (11) | 0.0203 (10) | 0.0094 (10) | 0.0181 (9) |
| C19 | 0.0418 (12) | 0.0365 (10) | 0.0326 (10) | 0.0262 (10) | 0.0113 (9) | 0.0157 (9) |
| C20 | 0.0313 (10) | 0.0340 (10) | 0.0278 (9) | 0.0178 (9) | 0.0073 (8) | 0.0145 (8) |
| O1—H1 | 0.8400 | C5—C6 | 1.393 (3) |
| O1—C1 | 1.365 (2) | C8—C9 | 1.388 (3) |
| O2—H2 | 0.8400 | C8—C13 | 1.396 (3) |
| O2—C20 | 1.356 (2) | C9—H9 | 0.9500 |
| N1—C7 | 1.479 (2) | C9—C10 | 1.380 (3) |
| N1—C8 | 1.402 (2) | C10—H10 | 0.9500 |
| N1—C14 | 1.344 (2) | C10—C11 | 1.396 (3) |
| N2—H2A | 0.8800 | C11—H11 | 0.9500 |
| N2—C13 | 1.378 (2) | C11—C12 | 1.374 (3) |
| N2—C14 | 1.337 (2) | C12—H12 | 0.9500 |
| C7—H7A | 0.9900 | C12—C13 | 1.394 (2) |
| C7—H7B | 0.9900 | C14—C15 | 1.458 (2) |
| C7—C6 | 1.505 (2) | C15—C16 | 1.400 (3) |
| C1—C2 | 1.393 (3) | C15—C20 | 1.396 (3) |
| C1—C6 | 1.381 (3) | C16—H16 | 0.9500 |
| C2—H2B | 0.9500 | C16—C17 | 1.371 (3) |
| C2—C3 | 1.380 (3) | C17—H17 | 0.9500 |
| C3—H3 | 0.9500 | C17—C18 | 1.385 (3) |
| C3—C4 | 1.373 (3) | C18—H18 | 0.9500 |
| C4—H4 | 0.9500 | C18—C19 | 1.375 (3) |
| C4—C5 | 1.391 (3) | C19—H19 | 0.9500 |
| C5—H5 | 0.9500 | C19—C20 | 1.391 (3) |
| C1—O1—H1 | 109.5 | C10—C9—C8 | 116.71 (18) |
| C20—O2—H2 | 109.5 | C10—C9—H9 | 121.6 |
| C8—N1—C7 | 126.87 (14) | C9—C10—H10 | 118.9 |
| C14—N1—C7 | 124.73 (14) | C9—C10—C11 | 122.14 (18) |
| C14—N1—C8 | 108.30 (14) | C11—C10—H10 | 118.9 |
| C13—N2—H2A | 125.2 | C10—C11—H11 | 119.2 |
| C14—N2—H2A | 125.2 | C12—C11—C10 | 121.63 (17) |
| C14—N2—C13 | 109.54 (15) | C12—C11—H11 | 119.2 |
| N1—C7—H7A | 109.2 | C11—C12—H12 | 121.8 |
| N1—C7—H7B | 109.2 | C11—C12—C13 | 116.42 (18) |
| N1—C7—C6 | 112.25 (14) | C13—C12—H12 | 121.8 |
| H7A—C7—H7B | 107.9 | N2—C13—C8 | 106.63 (15) |
| C6—C7—H7A | 109.2 | N2—C13—C12 | 131.29 (17) |
| C6—C7—H7B | 109.2 | C12—C13—C8 | 122.08 (17) |
| O1—C1—C2 | 122.67 (19) | N1—C14—C15 | 128.09 (16) |
| O1—C1—C6 | 116.49 (16) | N2—C14—N1 | 109.17 (15) |
| C6—C1—C2 | 120.84 (18) | N2—C14—C15 | 122.61 (15) |
| C1—C2—H2B | 120.4 | C16—C15—C14 | 118.21 (16) |
| C3—C2—C1 | 119.1 (2) | C20—C15—C14 | 122.35 (17) |
| C3—C2—H2B | 120.4 | C20—C15—C16 | 119.39 (17) |
| C2—C3—H3 | 119.5 | C15—C16—H16 | 119.5 |
| C4—C3—C2 | 121.02 (19) | C17—C16—C15 | 120.94 (18) |
| C4—C3—H3 | 119.5 | C17—C16—H16 | 119.5 |
| C3—C4—H4 | 120.2 | C16—C17—H17 | 120.5 |
| C3—C4—C5 | 119.60 (19) | C16—C17—C18 | 119.01 (19) |
| C5—C4—H4 | 120.2 | C18—C17—H17 | 120.5 |
| C4—C5—H5 | 119.8 | C17—C18—H18 | 119.4 |
| C4—C5—C6 | 120.3 (2) | C19—C18—C17 | 121.23 (18) |
| C6—C5—H5 | 119.8 | C19—C18—H18 | 119.4 |
| C1—C6—C7 | 119.68 (16) | C18—C19—H19 | 120.0 |
| C1—C6—C5 | 119.00 (18) | C18—C19—C20 | 120.08 (17) |
| C5—C6—C7 | 121.27 (18) | C20—C19—H19 | 120.0 |
| C9—C8—N1 | 132.62 (17) | O2—C20—C15 | 117.13 (16) |
| C9—C8—C13 | 121.01 (16) | O2—C20—C19 | 123.57 (16) |
| C13—C8—N1 | 106.36 (15) | C19—C20—C15 | 119.29 (17) |
| C8—C9—H9 | 121.6 | ||
| O1—C1—C2—C3 | 178.87 (18) | C8—C9—C10—C11 | −1.1 (3) |
| O1—C1—C6—C7 | 0.3 (2) | C9—C8—C13—N2 | −179.52 (17) |
| O1—C1—C6—C5 | −177.18 (16) | C9—C8—C13—C12 | 0.8 (3) |
| N1—C7—C6—C1 | 63.1 (2) | C9—C10—C11—C12 | 0.4 (3) |
| N1—C7—C6—C5 | −119.49 (18) | C10—C11—C12—C13 | 0.9 (3) |
| N1—C8—C9—C10 | −178.6 (2) | C11—C12—C13—N2 | 178.91 (19) |
| N1—C8—C13—N2 | −0.2 (2) | C11—C12—C13—C8 | −1.5 (3) |
| N1—C8—C13—C12 | −179.86 (17) | C13—N2—C14—N1 | −0.2 (2) |
| N1—C14—C15—C16 | 123.4 (2) | C13—N2—C14—C15 | 175.93 (16) |
| N1—C14—C15—C20 | −59.2 (3) | C13—C8—C9—C10 | 0.5 (3) |
| N2—C14—C15—C16 | −51.9 (3) | C14—N1—C7—C6 | −134.04 (18) |
| N2—C14—C15—C20 | 125.5 (2) | C14—N1—C8—C9 | 179.3 (2) |
| C7—N1—C8—C9 | 2.7 (3) | C14—N1—C8—C13 | 0.1 (2) |
| C7—N1—C8—C13 | −176.58 (17) | C14—N2—C13—C8 | 0.2 (2) |
| C7—N1—C14—N2 | 176.79 (16) | C14—N2—C13—C12 | 179.9 (2) |
| C7—N1—C14—C15 | 1.0 (3) | C14—C15—C16—C17 | 179.90 (18) |
| C1—C2—C3—C4 | −1.4 (3) | C14—C15—C20—O2 | −0.1 (3) |
| C2—C1—C6—C7 | −179.56 (16) | C14—C15—C20—C19 | −179.40 (17) |
| C2—C1—C6—C5 | 3.0 (3) | C15—C16—C17—C18 | −0.8 (3) |
| C2—C3—C4—C5 | 2.4 (3) | C16—C15—C20—O2 | 177.20 (16) |
| C3—C4—C5—C6 | −0.6 (3) | C16—C15—C20—C19 | −2.1 (3) |
| C4—C5—C6—C7 | −179.43 (17) | C16—C17—C18—C19 | −1.2 (3) |
| C4—C5—C6—C1 | −2.0 (3) | C17—C18—C19—C20 | 1.6 (3) |
| C6—C1—C2—C3 | −1.3 (3) | C18—C19—C20—O2 | −179.12 (17) |
| C8—N1—C7—C6 | 42.1 (2) | C18—C19—C20—C15 | 0.1 (3) |
| C8—N1—C14—N2 | 0.1 (2) | C20—C15—C16—C17 | 2.5 (3) |
| C8—N1—C14—C15 | −175.76 (18) |
| H··· | ||||
| O1—H1···Cl1i | 0.84 | 2.24 | 3.066 (2) | 169 |
| O2—H2···Cl1 | 0.84 | 2.23 | 3.071 (1) | 177 |
| N2—H2 | 0.88 | 2.23 | 3.084 (2) | 162 |
| C16—H16···O1iii | 0.95 | 2.57 | 3.253 (2) | 129 |
| C19—H19···Cl1 | 0.95 | 2.93 | 3.646 (2) | 134 |
| C7—H7 | 0.99 | 2.77 | 3.500 (2) | 131 |