Diphenylamino Groups Research Articles

Selective detection of cyanide ion using mechno-chemical synthesized fluorophore: 3-(4-(diphenylamino)phenyl)-1-(phenyl)prop‑2-en-1-one

A novel probe has been developed to find the cyanide ion pollutant in our environment. A new chalcone analog (E)-3-(4- (diphenyl amino) phenyl)-1-(phenyl) prop‑2-en-1-one was synthesized by solvents free mechano-chemical method. To detect numerous anions (CN−, F−, Cl−, Br−, NO3−, SO42−, PO43−, OH−, OAc−) in the DMSO medium, the probe's sensing capabilities were tested using UV–Vis absorption and fluorescence spectroscopy methods. The probe exhibited selectivity and sensitivity towards cyanide ions (CN−) in the presence of the various analytes. The interaction energies with the same anions and their sensing behavior through density functional theory (DFT) calculations were reported. The chalcone derivatives' higher electron affinity accelerates, which can also boost the compound's reactivity to cyanide anions following the intramolecular charge transfer (ICT) mechanism.

A Theoretical Investigation for Exploring the Potential Performance of Non-Fullerene Organic Solar Cells Through Side-Chain Engineering Having Diphenylamino Groups to Enhance Photovoltaic Properties.

The development of ecofriendly fabrication phenomenon is essential requirement for commercialization of non-fullerene acceptors. Recently, end-capped modeling is employed for computational design of five non-fullerene acceptors to elevate various photovoltaic properties. All new molecules are formulated by altering the peripheral acceptors of CH3-2F and DFT methodology is employed to explore the opto-electronic, morphological and charge transfer analysis. From the computational investigation, all reported molecules manifested red shifted absorption with remarkable reduced band gap. Among investigated molecules, FA1-FA3 evinced effectively decreased value of band gaps and designed molecules have low excitation energy justifying proficient charge transference. The lower values of binding energy of FA1 and FA2 suggest their facile exciton dissociation leading to improved charge mobility. By blending with J61 donor, FA4 have sufficiently enhanced value of VOC (1.72eV) and fill factor (0.9228). Energy loss of the model (R) is 0.57eV and statistical calculation demonstrate that all our modified molecules except FA3 has profoundly reduced energy loss compelling in its pivotal utilization. From accessible supportive outcomes of recent investigation, it is recommended that our modified chromophore exhibit remarkable noteworthy applications in solar cells for forthcoming innovations.

Effects of carbazolyl and diphenylamino substituents bearing methoxy groups on the performance of hole-transporting materials in OLEDs

Newly designed and synthesized derivatives of pentaphenylbenzene with methoxy-substituted carbazolyl or diphenylamino moieties were investigated to estimate their applicability as hole transport materials. Both the compounds exhibit high thermal stability. The intramolecular charge transfer is blocked for the film of the compound containing diphenylamino groups. The intermolecular charge transfer is induced in the film of carbazolyl-containing compound. The derivative of pentaphenylbenzene and diphenylamine exhibits higher hole drift mobility (2.4·10−3 cm2/V·s at the electric field of 5.5·105 V/cm) and by 0.1 eV lower ionization potential than the carbazolyl-containing compound. Both the compounds were utilized as hole-transporting materials in a series of organic light emitting diodes (OLEDs) based on of thermally activated delayed fluorescence. With the maximum values of external quantum efficiency of 25.9 % and power efficiency of 43.4 lm/W, OLEDs containing the layers of the synthesized compounds outperformed the device based on TCTA by 4 %, without the change in spectral properties. Variable angle spectroscopic ellipsometry revealed the moderate average roughness of the films of the compound deposited by the thermal vacuum evaporation technique with an arithmetic mean deviation of not more than 0.8 nm. The prominent hole transport characteristics of the compounds make them good candidates for utilization in optoelectronic devices.

Chemical, electrochemical, and quantum investigation into the use of an organophosphorus derivative to inhibit copper corrosion in acidic environments

In order to protect the copper against corrosion, a novel corrosion inhibitor known as diphenyl ((2-aminoethyl) amino) (4-methoxyphenyl) methyl) phosphonate (DAMP) was developed. Acid solutions of HCl and H2SO4 were the aggressive solutions employed in this study. Analysis using the FT-IR, 1H-NMR, 31P-NMR, 13C-NMR and BET confirmed that the DAMP was successfully synthesized. The anti-corrosion capabilities of DAMP are evaluated using a combination of chemical, electrochemical and quantum studies. The DAMP has been found to be crucial in preventing the corrosion of copper in both HCl and H2SO4 acid. This was obviously implied by the observation that the corrosion rate of copper in acid solutions decreased when DAMP was added. It is significant to note that 180 ppm produced the highest levels of inhibiting efficiency (96.6% for HCl and 95.2% for H2SO4). The tendency of DAMP to adsorb on the surface of copper through its hetero-atoms (O, N, and P) is the main factor for the anti-corrosion capabilities of DAMP. Results from SEM/EDX tests supported this. The actual adsorption takes place via various active centers, physical and chemical mechanisms that are coordinated with the estimated quantum parameters. Additionally, the adsorption of DAMP adheres to the Langmuir isotherm.

Multifunctional polyphosphazene grafted with triphenylamine and aminostilbene chromophore for electrochromic and sensor application

In this paper, a sequence of polyphosphazenes (PPZs) as electrochromic (EC) and sensor materials have been designed and synthesized by introducing chromophores, (4-(diphenyl amino)phenyl) methanol (CH1) for PPZ1, 3-(4-(dimethyl amino) phenyl)-2-(4hydroxyphenyl) acrylonitrile (CH2) for PPZ2, and CH1 and CH2 for PPZ3 into the main chain. In terms of EC performance, PPZ1 shows the best EC performance among the three PPZs which can achieve 60 % optical contrast at 690 nm with good cyclic stability within 1000 s and fast switching response time (tcolor/tbleach = 1.2 s/0.6 s). Compared to PPZ1, the oxidation potential of PPZ3 is reduced compared to PPZ1. PPZ2 and PPZ3 as sensors are more sensitive for the detection of 2,4,6-trinitrophenol (TNP) and trifluoroacetic acid (TFA) compared to PPZ1. What's more, PPZs can be used in memory devices with non-volatile flash memory performance and switching current ratios of 103:102.4:1, 104.7:101.3:1 and 103.5.:100.6:1 respectively. Therefore, PPZs have the promising prospect in optoelectronic field.

A Reversible Mechanochromic AIEgen Based on Triphenylamine for the Selective Detection of Vitamin B2 (Riboflavin) in Aqueous Media and Histotoxicity.

(E)-Ethyl 2-cyano-3-(4'-(diphenyl amino)-[1,1'-biphenyl]-4-yl) acrylate (RSJ) is a novel luminogen based on triphenylamine. It has been fully synthesized and characterized, exhibiting an incredible photophysical phenomenon known as aggregation-induced emission (AIE). This work describes a fluorescent sensor that detects vitamin B2 in mixed aqueous media with high selectivity and a low limit of detection as well as a mechanism for reversible mechanochromic luminescence. Moreover, the molecule was validated for its nontoxicity in water using a histotoxicological study. Fish subjected to two different concentrations of the "novel luminogen" that displayed photophysical phenomena during sensing of vitamin B2 (riboflavin) in mixed aqueous media did not exhibit any significant differences in the structural makeup of their liver, kidney, gills, brain, and muscle tissues when compared with the control group.

Synthesis and Optical Properties of Anion‐Responsive X‐shaped π‐Electronic System

AbstractThe properties of donor‐π‐acceptor molecules are strongly influenced by the electron density and configuration of both donor and acceptor moieties. In particular, X‐shaped molecules, where two linear π‐conjugation systems ended by donors and/or acceptors are crossed in their middle, are well‐known to separate frontier molecular orbitals, and the donor and acceptor strongly influence the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), respectively. A novel X‐shaped molecule, containing a diphenylamino group as the donor and a dimesitylboryl group as the acceptor, was synthesized to modulate the optical properties via anion complex formation. The X‐shaped molecule formed [1+1]‐ and [1+2]‐type anion complexes in solution, and a negative cooperative effect for the formation of the [1+2]‐type anion complex was observed. UV‐vis and fluorescence spectroscopy reveled the changes in the optical properties by the formation of anion complexes, with the spectral changes upon anion addition were consistent with the theoretical spectra obtained from time‐dependent density functional theory calculations. Furthermore, the X‐shaped molecule, which exhibits remarkable luminescence properties even in the solid state, demonstrated electroluminescent behavior.

Environment-sensitive indolenine-based hemisquaraine dyes: Synthesis, molecular structure, and spectral properties

Environment-sensitive fluorescent dyes are widely used in biomedical research, clinical diagnostics, molecular and cellular biology, analytical and bioanalytical chemistry. Many sensing dyes in the series of cyanines, styryls, BODIPY, squaraines, fluoresceins, and rhodamines among others have been developed and employed for these applications. Meanwhile, push-pull hemisquaraine dyes have been only moderately explored as the environment sensors. Herein, we developed a series of hemisquaraine dyes containing methylamino (MeH), dimethylamino (MeMe), phenylamino (PhH), phenylmethylamino (PhMe), and diphenylamino (PhPh) groups. These substituents were found to strongly affect sensitivity of the dyes towards H-bond formation, polarity, pH, viscosity, and the presence of bovine serum albumin (BSA), which aids the development of sensors for particular applications.

Nanographene Coupled with Interfacial Pyrene Derivatives for Thermally Stable Perovskite Solar Cells

Although high-efficiency perovskite solar cells (PSCs) have been achieved using a hole-extracting material, spiro-MeOTAD, thermal stability has been unattainable due to the low glass transition temperature of spiro-MeOTAD and additives therein. Here, we report on the use of nanographene-based hole-transporting materials coupled with a pyrene derivative as an interface modifier for thermally stable and high efficiency PSCs. Asymmetric methyl and methoxy groups are introduced in the diphenylamino group that is attached to the hexa-peri-hexabenzocoronene (HBC) nanographene core, coded HBC-DPAMeOMe. 1-Pyrenemethylammonium iodide is coupled to enhance the chemical interaction between perovskite and HBC-DPAMeOMe, which leads to a power conversion efficiency over 23%. A thermal stability test at 85 °C for 1000 h reveals that 83.6% of the initial efficiency (23.04% → 19.25%) is maintained for the device with HBC-DPAMeOMe, while a significant degradation from 20.69% to 5.08% is observed for the device with spiro-MeOTAD. Nanographene-based hole conductors shed light on the thermal stability issue in PSCs.

Solvent-Controlled Photoswitching of Azobenzene: An Excited State Shuttle.

Light controlled excited state trans-cis isomerization process is a key to the development of conversion of light energy to mechanical motion at the molecular level. Considerable efforts have been made in tuning the isomerization process with electron donor and acceptor substituents by altering the excited state reaction coordinate. Here, we report a two novel push-pull series of para-diethylamino (DEA) and diphenylamino (DPA) substituted (E)-4'-((4-(diethylamino)phenyl)diazenyl)-N,N-diphenyl-[1,1'-biphenyl]-4-amine (1) and (E)-4'-((4-(diphenylamino)phenyl)diazenyl)-N,N-diphenyl-[1,1'-biphenyl]-4-amine (2). Compound 1 and 2 undergoes both photochemical and photophysical excited state deactivation pathways which can be controlled by varying the solvent polarity. These structural motifs of 1 and 2 would undergo torsional motions upon excitation to exhibit either trans → cis photoisomerization or to form a twisted intramolecular charge transfer state and both the process originates from the same excited state and competes with each other. Thus, alternations in the surrounding environment such as solvent polarity, solution viscosity, and protonation were employed to understand the preferential excited state deactivation pathway and thereby these systems could be employed as a new class of azobenzene-based luminescent photochromic molecules. For instance, in nonpolar solvent, toluene photoisomerization is preferred over TICT, but polar solvent, ethanol preferentially stabilizes the TICT state by virtue of N-C rotation which renders the energy barrier unfavourable for photoisomerization. The photostationary state of 1 in toluene is predominantly the Z isomer, whereas in ethanol E isomer is nearly two-fold higher than the Z isomer. These feature sets up a new approach towards the construction of multinary molecular switches and subsequent development in diverse fields.

Novel pH-activatable NIR fluorogenic spray mediated near-instant and precise tumor margins identification in human cancer tissues for surgical resection.

Rationale: Challenges such as developing a universal tumor-specific probe for tumor margin identification in diverse tumors with an easy-operative and fast-imaging pattern still exist. Hence, in the present study, a rapidly "off-on" near-infrared (NIR) fluorescent probe NBD with pH-activatable fluorescence and a large Stokes shift was constructed for spray mediated near-instant and precise clinical tumor margins identification. Methods: NBD was designed and synthesized by introducing both diphenyl amino group and benzo[e]indolium to β-carboline at C-6 and C-3 positions respectively. The optical properties of NBD was characterized by absorption spectra, fluorescence spectra. Subsequently, we investigated its pH-dependent mechanism by 1H NMR and density functional theory (DFT) calculation. NBD was further under deeper investigation into its imaging performance in nude mice models (subcutaneous, orthotopic, metastatic tumor), and clinical tissues from patients with three clinically representative tumors (liver cancer, colon cancer, and lung cancer). Results: It was found that NBD had NIR fluorescence (742 nm), a large Stokes shift (160 nm), and two-photon absorbance (1040 nm). Fluorescence quantum yield (ФF) increased by 5.5-fold when pH decreased from 7.4 to 4.0, to show pH-dependent property. Furthermore, NBD could not only selectively light up all four cancer cell lines, but also delineate xenograft tumor and orthotopic microtumor to guide surgical tumor resection, and track metastatic tissues. Particularly, after simple topical spray (three minutes later), NBD could rapidly and precisely distinguish the boundary ranges of three kinds of clinical cancer specimens including liver, colon, and lung cancers, with high tumor-to-normal tissue signal ratios (6.48~9.80). Conclusions: Therefore, the proposed fluorescent probe NBD may serve as a versatile NIR fluorogenic spray for the near-instant visualization of tumor margins and assisting surgeons in surgerical resection of clinical cancers.

Tuning the Charge Transfer in λ5-Phosphinines with Amino Substituents.

We report the substitution of λ5-phosphinines (2,6-dicarbonitrile diphenyl-1-λ5-phosphinine) with an amino group. The impact of these modifications on both the optical and redox properties is investigated using a joint experimental/theoretical approach. In particular, we show that the choice of the donor diphenylamino group dramatically impacts the nature of the charge transfer. The use of di(methoxyphenyl)amine redshifts the optical properties and allows thermally activated delayed fluorescence in the solid state. Finally, we demonstrated that λ5-phosphinines with an amino group can be used as active emitters in an electroluminescent device.

Design, Regioselective Synthesis, and Photophysical Properties of Perfluoronaphthalene-Based Donor-Acceptor-Donor Fluorescent Dyes.

A one-step route to a series of perfluoronaphthalene-based donor (D)-acceptor (A)-D fluorescent dyes with various electron-donating groups was developed. The perfluoronaphthalene moiety in the D-A-D dyes served as a good electron-accepting aromatic ring with excellent intramolecular charge transfer properties, as determined by density functional theory calculations and measurements of the fluorescence properties in solution, in poly(methyl methacrylate) (PMMA) films, and in crystal form. Notably, replacing the naphthalene ring with perfluoronaphthalene in the D-A-D dyes carrying the phenothiazine moiety not only stabilized the highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels but also reduced the energy band gap to change the emission color from blue to yellow. Among the four synthesized perfluoronaphthalene D-A-D dyes, those bearing diphenylamino groups afforded the best fluorescence quantum yields in Et2O solution (0.60) and in PMMA film (0.65) because the propeller structure of the diphenylamino group that acts as a donor substituent effectively suppresses radiation-free deactivation. In contrast, in the crystalline state, the carbazoyl-bearing D-A-D dye provided the best fluorescence quantum yield (0.35) because the radiation-free inactivation was suppressed by π-πF stacking at the donor site, which was confirmed by single-crystal X-ray analysis.

Near‐Infrared and Dual Emissions of Diphenylamino Group‐Substituted Malachite Green Derivatives

AbstractNovel triarylmethanols and triarylmethyl cations with diphenylamino groups were designed and synthesized. The triarylmethyl cations exhibited near‐infrared (NIR) emission in toluene solution, solid film state, and polystyrene (PS) film. The emission intensities of the triarylmethyl cations were strongest in the PS film. The relative quantum yield of the PS film increased as the number of diphenylamino groups increased. In addition, triarylmethanols exhibit dual emission in their aggregated state owing to the intermolecular interactions between triphenyl amine moieties and/or hydroxy groups. These findings are interesting because NIR and dual emissions are not observed in the dimethylamino group‐substituted triarylmethyl cation, which is referred to as the “malachite green,” and the corresponding triarylmethanol, respectively.

Coumarin-based two-photon AIE fluorophores: Photophysical properties and biological application

Based on the coumarin skeleton, we deliberately designed two groups of fluorophores, termed as Coum-R and Naph-Coum-R, using the diphenylamino group as the electron donor, which displayed long-wavelength emissions (red spectral region), large Stokes shift (up to 204 nm), superior AIE performance, and large two-photon absorbance cross-sections (as high as 365 GM). The electron-withdrawing substituents at the 3-position of these dyes could induce a significant red-shift in their emission spectra. Preliminary imaging experiments demonstrated the capability of these dyes as two-photon fluorophores for specifically staining lipid droplets in living cells.

9‐(Diphenylphosphoryl)‐10‐(phenylethynyl)anthracene Derivatives: Synthesis and Implications for the Substituent and Solvent Effects on the Light‐Emitting Properties

AbstractHerein, we report a series of 9‐(diphenylphosphoryl)‐10‐(phenylethynyl)anthracenes (DPPPEAs) as novel fluorescent 9,10‐disubstituted anthracene derivatives. The DPPPEAs were prepared by Sonogashira coupling of (10‐bromoanthracen‐9‐yl)diphenylphosphine oxide with terminal arylacetylenes, and their structures were fully characterized. UV/Vis fluorescence spectroscopy and theoretical calculations were used to evaluate substituent effects on fluorescence properties of DPPPEAs. The nature of emissive excited state of DPPPEAs was found to vary greatly depending on the substituent, solvent, and temperature. Unsubstituted DPPPEA emitted intense fluorescence from locally excited (LE) state, whereas donor‐acceptor (D‐A) type DPPPEAs substituted with diphenylamino groups showed strong solvatofluorochromism derived from the charge‐transfer (CT) state. Notably, carbazolyl derivatives exhibited fluorescence from LE hybridized with CT state. The disappearance of CT emission in rigid media suggests that solvent reorganization plays a crucial role in producing large Stokes shifts of D‐A type derivatives. The DPPPEAs have also been found to function as annihilators in porphyrin‐sensitized triplet–triplet annihilation processes.

D–π–A-type fluorinated tolanes with a diphenylamino group: crystal polymorphism formation and photophysical behavior

Ph2N-Substituted fluorinated tolanes produced two polymorphisms, which display a distinct photoluminescence behavior; one polymorphism showed green PL and the other exhibited yellow PL.

Sonosensitized Aggregation-Induced Emission Dots with Capacities of Immunogenic Cell Death Induction and Multivalent Blocking of Programmed Cell Death-Ligand 1 for Amplified Antitumor Immunotherapy

Sonosensitized Aggregation-Induced Emission Dots with Capacities of Immunogenic Cell Death Induction and Multivalent Blocking of Programmed Cell Death-Ligand 1 for Amplified Antitumor Immunotherapy

Phosphine-based push-pull AIE fluorophores: Synthesis, photophysical properties, and TD-DFT studies

Herein, we report the design and characterization of a novel series of four push-pull fluorophores using diphenylphosphino as an electron-donating terminal group (P-chromophores). The spectroscopic properties in solution, the aggregation-induced emission (AIE) properties, as well as the emission properties in the solid state were studied and compared with those of the diphenylamino-analogues (N-chromophores). Comparative analysis of the crystalline structures coupled with density functional theory calculations revealed that the diphenylphosphino group adopts a pyramidal geometry, whereas a trigonal planar configuration around the N-center is observed for the diphenylamino group. Consequently, the phosphorous lone pair is localized on the upper side of the average chromophore plan and considerable geometrical change of the P-center can occur between the ground state and the first excited state, explaining the much larger Stokes shift observed (10 000 cm−1) for the P-chromophores compared to the N-analogues.

Substituent effect on emission of flavonolate-boron difluoride complexes: The role of π-system for dual-state (solution and solid) emission

In a quest for the still elusive dual-state emission (DSE), i.e., intense emissions both in solution and in the solid state, the luminescence properties of novel boron difluoride complexes with flavonolates bearing substituent(s) at the B ring (R: 4-Ph (2b); 4-OPh (2c); 4-NPh2 (2d); 2,6-Me2 (2e)) have been investigated. The emission intensity and maximum wavelength are strongly influenced by the electronic and steric factors of the substituents, which are responsible for the character of the π-conjugated system over the ligand. Complexes 2b and 2c with a rigid flat π-skeleton exhibited DSE (emission quantum yield (Φ) ≥ 0.34). Complex 2d bearing a rotatable diphenylamino group showed an aggregation-induced enhanced emission (AIEE), that is strong (Φ = 0.38) in the solid state but weak (Φ = 0.13) in CH2Cl2. Thus, 2b–2d exhibited intense solid-state emissions, although the corresponding ligands presented quenched solid-state emissions. Conversely, complex 2e, in which the B ring adopted a twisted position from the fused AC ring, that is, a twisted π-system, exhibited an aggregation-caused quenching (ACQ) resulting in an intense (Φ = 0.50) and a weak (Φ = 0.02) emission in CH2Cl2 and the solid state, respectively. This work provides important insights into the role of the π-system in the changeover of emission features in dual-state.