Indolium Iodide Research Articles

Evolution of physicochemical properties of 2-(2-(4-(4-chloro) phenyl) vinyl)-1, 1, 3-trimethyl-1H-benzo[e] Indolium iodide via experimental and quantum chemical calculation for third-harmonic generation applications

The synthesis, crystal structure, and physicochemical properties of new Indolium based nonlinear optical crystal of 2-(2-(4-(4-chloro) phenyl) vinyl)-1, 1, 3-trimethyl-1H-benzo[e] Indolium iodide (CBI) is reported here. The title crystal was grown by slow evaporation technique using methanol as a solvent and it is subjected to a single crystal X-ray diffraction study to confirm the crystallographic structure and found that it belongs to the monoclinic crystal system with a space group of P21/n. The band gap and optical window of the material are studied from UV-visible spectroscopic analysis, and the corresponding values are 4.2 eV and 295–800 nm, respectively. Thermal analysis reveals that the grown crystal is thermally stable up to 264°C and the high-temperature stability is favorable for industrial applications. Furthermore, we have studied the dielectric properties such as dielectric constant and dielectric losses and they are investigated by impedance spectroscopic analysis at various temperatures. The electronic charge transfers on the molecules are studied from the density functional theory. The various intermolecular interactions which are existed in the crystal are explored from Hirshfeld surface analysis. Finally, the Z-scan studies parameters expose that title crystal is a potential material for third-harmonic generation applications. The overall structural studies and functional properties disclose that the grown crystal is well suitable for third-harmonic generation applications.

Cyanine-based Fluorescent Probe for Cyanide Ion Detection.

Cyanine-based probe-possessing indolium iodide and indole unit were synthesized in two-step with easy available raw material: a potential probe for the cyanide ion detection. The detecting ability of the probe was investigated and confirmed by a visual and instrumental approach. A noticeable color change from orange to colorless obtained only for cyanide ions and other added ions does not impart any changes visually and through UV and Fluorescence technique. To confirm the mechanism of sensing 1H-NMR recorded. From the result, the peak belonging toN-methyl displayed an upfield shift from 4.01 δ ppm to 2.74 δ ppm due to the disappearance of indolium iodide ion and the olefin protons peaks were shifted from 7.19 to 6.17 and 8.70 to 7.20 δ ppm confirms the nucleophilic addition of cyanide ion to the probe. Test kit from filter paper prepared for the real-time monitoring cyanide ion. The prepared strip is effective in detecting cyanide ion with a visual color change.

Synthesis, optical properties and in vitro cell viability of novel spiropyrans and their photostationary states

A novel class of spiropyran (SP) was synthesized using a multistep process that involves three key intermediates: (a) diazonium-tetrafluoroborate, (b) hydrazine and (c) indolium iodide. Single crystal X-ray spectroscopy was used to confirm the structure of one of the analogues. The SP analogues were confirmed as being able to isomerize and attain a photostationary state (PSS) upon irradiation with ultraviolet light (UV, 365 nm) in an aqueous environment. UV–visible absorption spectra were recorded to confirm the isomerization properties. The ability of the synthesized compounds to induce growth inhibition of HeLa cervical cancer cells was assessed via the MTT assay after incubation with either the SP or their PSS. The IC 50 values of two PSS ( PSS-2 , 4 ), were observed to be around 14 ± 4 fold lower (26 ± 3 μM) than their corresponding SPs. The most cytotoxic compounds SP-7 and PSS-7 showed the lowest IC 50 values (12 μM). An in vitro tubulin polymerization assay showed that SP - 7 and PSS-7 exhibited the greatest difference in tubulin inhibition relative to unirradiated SP-1 and SP-4 .

A novel colorimetric and fluorescent probe for simultaneous detection of SO32-/HSO3- and HSO4- by different emission channels and its bioimaging in living cells

A novel fluorescent probe (E)-3-ethyl-2-(4-hydroxystyryl)-1,1-di-methyl-1H-benzo-[e]indolium iodide (probe EDB) based on benzo[e]indolium was synthesized, which provided the simultaneous detection of SO32-/HSO3- and HSO4- ion with different emission channels. Based on the principle of ion-induced rotation-displaced H-aggregates, when treated with NaHSO4, a fluorescence enhancement at 580nm was observed with the excitation wavelength at 420nm. While, in the advantage of the nucleophilic addition of SO32- to the vinyl group, strong fluorescence was obtained at 455nm when treated with Na2SO3 with the excitation wavelength at 320nm, along with obvious color change by naked eyes. So the probe could be applied to sense SO32-/HSO3- and HSO4- ion via different excited and emission channels simultaneously. The probe was also applicable for fluorescence imagings of bisulfite and hydrosulfate in HeLa cells.

An iridium complex-based phosphorescent probe for recognition to bisulfite and cyanide in neutral aqueous system

A newly designed cyclometalated iridium complex Ir(mepi)(ppy)2 (2, Hppy=2-phenylpyridine, Hmepi=3,3-dimethyl-1-ethyl-2-(4-(pyridin-2-yl)styryl)indolium iodide (1)) was successfully synthesized for the rapid detection of HSO3− and CN−. For complex 2, it is interesting that the selective 1,4-addition reaction with HSO3− in aerated DMSO/PBS buffer can be visualized by intense turn-on green emission. However, the 1,2-addition reaction with CN− resulted in an emission color change from colorless to orange-yellow. Furthermore, the limits of detection for HSO3− and CN− were calculated as low as 0.049 and 0.15μM, respectively. The results indicate that the two anions can be detected selectively and separately by naked-eyes in neutral aqueous system. As the typical interfering anion for detecting HSO3−, HS− led to the almost similar emission change that was caused by HSO3−. As a result, the reaction between 2 and HS− could be assigned as 1,4-addition rather than 1,2-addition reaction, which was further confirmed by the 1H NMR spectra changes of the ligand with these representative anions (HSO3−, HS− and CN−).

Ratiometric fluorescent probes for ClO− and in vivo applications

Newly synthesized 1,8-naphthalimide derivatives, 1 and 2, are found to detect specifically ClO− in presence of large excess of other competing ions with associated changes in their optical and fluorescence spectral behavior. These spectral changes are significant enough in the visible region of the spectrum and thus, allow the visual detection. The detection limit is low as 10−8 M. 1 and 2 could be used as ratiometric sensors for detection of ClO− based on the intramolecular charge transfer (ICT) process involving the donor 1,8-naphthalimide and the acceptor indolium iodide. Further, confocal laser microscopic studies confirmed that the probe 1 could also be used as imaging probe for detection of ClO− in HepG2 cells.

A ratiometric fluorescence probe for monitoring cyanide ion in live cells

A ratiometric emission fluorescent probe 1,1-dimethyl-3-ethyl-2-(2-(N-ethyl-carbazol-3-yl)-vinyl)-1H-benzo[e]indolium iodide (Probe) is facilely synthesized via the ethylene bridging of N-ethylcarbazole-3-formaldehyde and 1,1,2-trimethyl-3-ethyl-1H-benz[e]indolium iodide, which is a useful fluorescent probe for monitoring cyanide ion at extremely low concentrations, quantitatively. The detection of cyanide is performed via the nucleophilic attack of cyanide toward the benzo[e]indolium group of the probe, resulting in a prominent fluorescence ratiometric change and a color change. The titration experiments for CN− show that it exhibits a large Stokes shift (92nm), high selectivity, excellent sensitivity and good stability for CN− sensing in DMSO system. The detection limit of Probe for CN− is found to be 0.23μM. Furthermore, the probe has excellent cell membrane permeability and is applied successfully to rapidly detect CN− in living cells.

Recent progress in acentric core structures for highly efficient nonlinear optical crystals and their supramolecular interactions and terahertz applications

During the past decade, various new types of organic nonlinear optical crystals have been developed to overcome the benchmark stilbazolium DAST (4-(4-(N,N-dimethylamino)styryl)-1-methylpyridinium 4-methylbenzenesulfonate) crystal. Here, we review the acentric core structures used in recently developed organic nonlinear optical crystals exhibiting high macroscopic second-order optical nonlinearity, along with their supramolecular interactions and THz applications. The nonlinear optical acentric core structures such as neutral CLP (configurationally locked polyene based on phenyltriene), ionic pyridinium-based N-alkyl DAS (4-(4-(N,N-dimethylamino)styryl)-1-alkylpyridinium benzenesulfonate) and N-phenyl DAP ((4-(N,N-dimethylamino)styryl)-1-phenylpyridinium hexafluorophosphate), ionic quinolinium-based HMQ (2-(4-hydroxy-3-methoxystyryl)-1-methylquinolinium benzenesulfonate) and OHQ (2-(4-hydroxystyryl)-1-methylquinolinium benzenesulfonate) and benzoindolium-based DBI (2-(4-(dimethylamino)styryl)-1,3,3-trimethyl-3H-benzo[g]indolium iodide) exhibit comparable or enhanced physical properties compared to DAST crystals. Organic crystals introducing an identical acentric core structure often exhibit similar molecular alignment features with analogous supramolecular interactions. We also discuss the nonlinear optical properties and potential applications of these materials, in particular their very promising THz photonic applications.

Hydrophilic Indolium Cycloruthenated Complex System for Visual Detection of Bisulfite with a Large Red Shift in Absorption

Bisulfite, as an important additive in foodstuffs, is one of the most widely distributed environmental pollutants. The excessive intake of bisulfite may cause asthmatic attacks and allergic reactions. Therefore, the determination and visual detection of bisulfite are very important. Herein, a newly designed hydrophilic indolium cycloruthenated complex, [Ru(mepbi)(bpy)2](+) [1; bpy = 2,2'-bipyridine and Hmepbi = 3,3-dimethyl-1-ethyl-2-[4-(pyridin-2-yl)styryl]benzo[e]indolium iodide (3)], was successfully synthesized and used as a bisulfite probe. The bisulfite underwent a 1,4-addition reaction with complex 1 in PBS buffer (10 mM, pH 7.40), resulting in a dramatic change in absorption spectra with a red shift of over 100 nm and a remarkable change in solution color from yellow to pink. It is worth noting that this obvious bathochromic shift is rarely observed in the detection of bisulfite through an addition reaction. The detection limit was calculated to be as low as 0.12 μM by UV-vis absorption spectroscopy. Moreover, complex 1 was also used to detect bisulfite in sugar samples (granulated and crystal sugar) with good recovery.

Inverse Analysis of near Infrared Transmission Spectra for Triarylamine, Tetraaryldiamine, Nickel Dithiolene and Indolium-Iodide Dyes

An inverse analysis of transmission spectra for triarylamine, tetraaryldiamine, nickel dithiolene and indolium iodide dyes in solution is presented. This analysis employs a parametric model of transmission through a sample of finite thickness, where the permittivity function is represented parametrically by a linear combination of Lorentzian functions. The results of this analysis provide estimates of permittivity functions, which can be adopted as input data to other types of models, such as those for prediction of transmission and reflectivity spectra for composites containing mixtures of dyes and other materials.

Co-sensitization with near-IR absorbing cyanine dye to improve photoelectric conversion of dye-sensitized solar cells

Two carboxylated cyanine dyes, 3-butyl-2-[3-(1-butyl-5-carboxy-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)-1-propen-1-yl]-1,1-dimethyl-7-[1-[2-[6-(4-morpholinyl)-1,3-dioxo-1H-benz[ de]isoquinolin-2(3H)-yl]ethyl]-1H-1,2,3-triazol-4-yl]-1H-Benz[ e]indolium iodide (A), 2-[5-(1-butyl-5-carboxy-1,3-dihydro-3,3-dimethyl-2H-indol-2-ylidene)-1,3-pentadienyl]-3-ethyl-1,1-dimethyl-1H-Benz[ e]indolium iodide (B), have been prepared and their photophysical and electrochemical properties have been investigated. A, B and their mixtures (AB) were used as sensitizers in nanocrystalline TiO 2 solar cells to improve photoelectric conversion efficiency. It was found that the solar cell sensitized with A3B1 (molar ratio: A:B = 3:1) generated a high power conversion efficiency of 3.0% under AM1.5G illumination (100 mW cm −2), indicating that co-sensitization is a promising method to improve the photoelectrical properties of dye-sensitized solar cells.

A new study on solid-state cyanine dye-sensitized solar cells

A new cyanine dye, 7-{1-[2-(4-morpholine-1,8-naphthalimide)ethyl]-1H-1,2,3-triazol-4-}-2-[3-(5-carboxyl-1,3-dihydro-3,3-dimethyl-1-butyl-indolin-2-methylene)-propenyl]-1,1-dimethyl-3-buty-1H-benzo[e]indolium iodide (BIDC), has been synthesized and identified with regard to its structure and photoelectrochemical properties used as a sensitizer on dye-sensitized solar cells. A novel solid-state electrolyte with polyaniline-loaded carbon black (PACB)-1-methyl-3-propylimidazolium iodide (MPII) composite was investigated on these dye-sensitized solar cells (DSCs). The short-circuit photocurrent density (Jsc), open-circuit photovoltage (Voc) and fill factor (ff) under 200 W/m2 white light from a xenon lamp are 0.44 mA/cm2, 550 mV and 0.58, respectively, yielding an overall conversion efficiency (η) of 0.7%. The most merit of the solid-sate electrolyte was free of volatile and flammable fluid components and easy of encapsulation for DSCs.

Photovoltaic properties of three new cyanine dyes for dye-sensitized solar cells

Three carboxylated cyanine dyes, 2-[(1-butyl-3,3-dimethyl-5-carboxylindoline-2-ylidene)propenyl]-[1-butyl-3,3-dimethyl-7-(1-ethyl-1H-1,2,3-triazole-4-yl]-1H-benz[e]indolium iodide (), 2-[(1-butyl-3,3-dimethyl-5-carboxyl-indoline-2-ylidene)propenyl]-{1-butyl-3,3-dimethyl-7-[(4-piperidine-N-ethyl-1,8-naphthalimide)-1H-1,2,3-triazole-4-yl]}-1H-benz[e]indolium iodide (Cy2) and 2-[(1-butyl-3,3-dimethyl-5-carboxyl-indoline-2-ylidene)propenyl)-[1-butyl-3,3-dimethyl-7-{(4-piperidine-N-butyl-1,8-naphthalimide)-1H-1,2,3-triazole-4-yl}]-1H-benz[e]indolium iodide (Cy3), have been synthesized and characterized with regard to their structures and electrochemical properties. Upon adsorption onto a TiO(2) electrode, the absorption spectra of the three cyanine dyes are all broadened to both red and blue sides compared with their respective spectra in an acetonitrile and ethanol mixture. Cy2 and Cy3, containing a naphthalimide group, have stronger absorption intensities and broader absorption spectra than , which consequently leads to better light-to-electricity conversion properties. Among the three cyanine dyes, generated the highest photoelectric conversion yield of 4.80% (J(sc) = 14.5 mA cm(-2), V(oc) = 500 mV, FF = 0.49) under illumination with 75 mW cm(-2) white light from a Xe lamp.

Photoelectric conversion properties of four novel carboxylated hemicyanine dyes on TiO2 electrode

Four hemicyanine derivatives, 2-[4-(N-ethyl-N-carboxyethyl)amino]phenylethenyl-1,3,3-trimethyl-3H-indolium iodide (BIDC1), 2-[4-(N,N-dicarboxyethyl)amino]phenylethenyl-1,3,3-trimethyl-3H-indolium iodide (BIDC2), 2-[4-(N-ethyl-N-carboxyethyl)amino]phenylethenyl-1,1,3-trimethyl-1H-benz[e]indolium iodide (BIDC3) and 2-[4-(N,N-dicarboxyethyl)amino]phenylethenyl-1,1,3-trimethyl-1H-benz[e]indolium iodide (BIDC4), have been synthesized and identified with regard to their structures and electrochemical properties. It is found that the absorption spectra of BIDC3 and BIDC4 are broader than that of BIDC1 and BIDC2 because the former two have one more benzene ring on the electron acceptor side. Upon adsorption on a TiO2 electrode, the absorption spectra of the four BIDC dyes are all broadened forward to both red and blue sides compared with their respective spectra in ethanol solution. BIDC2 (or BIDC4), bearing two carboxyl groups, has about two (or three) times more adsorption and a broader absorption spectrum on TiO2 film compared with BIDC1 (or BIDC3), which consequently leads to a better light-to-electricity conversion property. Among the four hemicyanine dyes, BIDC4 generated the highest photoelectric conversion yield of 4.9%, with a short-circuit photocurrent of 21.4 mA cm−2, an open-circuit voltage of 424 mV, and a fill factor of 0.49 under irradiation with 90.0 mW cm−2 white light from a Xe lamp.