Phosphonium Iodide Research Articles

Phosphonium Iodide Featuring Blue Thermally Activated Delayed Fluorescence for Highly Efficient X‐Ray Scintillator

AbstractOrganic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X‐ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I−) serve as the electron donor. The prepared butyl(2‐[2‐(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4‐I) exhibits bright blue emission and an ultra‐high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n‐π and anion‐π stacking in solid‐state C4‐I. Photophysical studies of C4‐I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near‐pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X‐ray attenuation ability endowed by I, C4‐I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s−1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X‐ray attenuation ability, and excellent scintillator performance.

Phosphonium Iodide Featuring Blue Thermally Activated Delayed Fluorescence for Highly Efficient X-Ray Scintillator.

Organic scintillators are praised for their abundant element reserves, facile preparation procedures, and rich structures. However, the weak X-ray attenuation ability and low exciton utilization efficiency result in unsatisfactory scintillation performance. Herein, a new family of highly efficient organic phosphonium halide salts with thermally activated delayed fluorescence (TADF) are designed by innovatively adopting quaternary phosphonium as the electron acceptor, while dimethylamine group and halide anions (I-) serve as the electron donor. The prepared butyl(2-[2-(dimethylamino)phenyl]phenyl)diphenylphosphonium iodide (C4-I) exhibits bright blue emission and an ultra-high photoluminescence quantum yield (PLQY) of 100 %. Efficient charge transfer is realized through the unique n-π and anion-π stacking in solid-state C4-I. Photophysical studies of C4-I suggest that the incorporation of I accounts for high intersystem crossing rate (kISC) and reverse intersystem crossing rate (kRISC), suppressing the intrinsic prompt fluorescence and enabling near-pure TADF emission at room temperature. Benefitting from the large Stokes shift, high PLQY, efficient exciton utilization, and remarkable X-ray attenuation ability endowed by I, C4-I delivers an outstanding light yield of 80721 photons/MeV and a low limit of detection (LoD) of 22.79 nGy ⋅ s-1. This work would provide a rational design concept and open up an appealing road for developing efficient organic scintillators with tunable emission, strong X-ray attenuation ability, and excellent scintillator performance.

Phosphine chalcogenides and their derivatives from red phosphorus and functionalized pyridines, imidazoles, pyrazoles and their antimicrobial and cytostatic activity

Tertiary phosphine oxides, phosphine sulfides, and phosphine selenides containing pyridine, imidazole, and pyrazole groups have been synthesized via the reaction of elemental phosphorus or secondary phosphine oxides with functional pyridines, imidazoles, and pyrazoles. Alkyl tris(2-pyridylethyl)phosphonium iodide and bromide are also obtained by quaternization of the corresponding phosphine. Antimicrobial activity of the synthesized compounds, including nitrogen-containing heterocycles, phosphorus, selenium, and sulfur, with respect to Enterococcus durans, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa microorganisms is evaluated. It is found that phosphine chalcogenides bearing imidazole (14, 19), pyrazole (13), and pyridine fragments (5, 9) and phosphonium salts (11, 12) can be considered as new promising antibacterial agents. For some synthesized compounds, LC50 is determined. Phosphine oxide with methylpyrazole fragments (13) and phosphonium salts (11, 12) show strong profile of antimicrobial activity, and cytotoxic effect of phosphonium bromide having a long chain radical (12) is by order of magnitude higher than that of cisplatin. We believe that the results obtained may contribute to the development of highly effective agents for the treatment and prevention of bacterial infections and cancers.

Perovskite grain wrapping by converting interfaces and grain boundaries into robust and water-insoluble low-dimensional perovskites.

Stabilizing perovskite solar cells requires consideration of all defective sites in the devices. Substantial efforts have been devoted to interfaces, while stabilization of grain boundaries received less attention. Here, we report on a molecule tributyl(methyl)phosphonium iodide (TPI), which can convert perovskite into a wide bandgap one-dimensional (1D) perovskite that is mechanically robust and water insoluble. Mixing TPI with perovskite precursor results in a wrapping of perovskite grains with both grain surfaces and grain boundaries converted into several nanometer-thick 1D perovskites during the grain formation process as observed by direct mapping. The grain wrapping passivates the grain boundaries, enhances their resistance to moisture, and reduces the iodine released during light soaking. The perovskite films with wrapped grains are more stable under heat and light. The best device with wrapped grains maintained 92.2% of its highest efficiency after light soaking under 1-sun illumination for 1900 hours at 55°C open-circuit condition.

Visible-Light-Induced Selective Photolysis of Phosphonium Iodide Salts for Monofluoromethylations.

The sigma (σ)-hole effect has emerged as a promising tool to construct novel architectures endowed with new properties. A simple yet effective strategy for the generation of monofluoromethyl radicals is a continuing challenge within the synthetic community. Fluoromethylphosphonium salts are easily available, air- and thermally stable, as well as simple-to-handle. Herein, we report the ability of the σ-hole effect to facilitate the visible-light-triggered photolysis of phosphonium iodide salts, a charge-transfer complex, selectively giving fluoromethyl radicals. The usefulness and versatility of this new protocol are demonstrated through the mono-, di-, and trifluoromethylation of a variety of alkenes.

Visible‐Light‐Induced Selective Photolysis of Phosphonium Iodide Salts for Monofluoromethylations

AbstractThe sigma (σ)‐hole effect has emerged as a promising tool to construct novel architectures endowed with new properties. A simple yet effective strategy for the generation of monofluoromethyl radicals is a continuing challenge within the synthetic community. Fluoromethylphosphonium salts are easily available, air‐ and thermally stable, as well as simple‐to‐handle. Herein, we report the ability of the σ‐hole effect to facilitate the visible‐light‐triggered photolysis of phosphonium iodide salts, a charge‐transfer complex, selectively giving fluoromethyl radicals. The usefulness and versatility of this new protocol are demonstrated through the mono‐, di‐, and trifluoromethylation of a variety of alkenes.

Catalytic, Kinetic, and Mechanistic Insights into the Fixation of CO2 with Epoxides Catalyzed by Phenol-Functionalized Phosphonium Salts.

A series of hydroxy‐functionalized phosphonium salts were studied as bifunctional catalysts for the conversion of CO2 with epoxides under mild and solvent‐free conditions. The reaction in the presence of a phenol‐based phosphonium iodide proceeded via a first order rection kinetic with respect to the substrate. Notably, in contrast to the aliphatic analogue, the phenol‐based catalyst showed no product inhibition. The temperature dependence of the reaction rate was investigated, and the activation energy for the model reaction was determined from an Arrhenius‐plot (E a=39.6 kJ mol−1). The substrate scope was also evaluated. Under the optimized reaction conditions, 20 terminal epoxides were converted at room temperature to the corresponding cyclic carbonates, which were isolated in yields up to 99 %. The reaction is easily scalable and was performed on a scale up to 50 g substrate. Moreover, this method was applied in the synthesis of the antitussive agent dropropizine starting from epichlorohydrin and phenylpiperazine. Furthermore, DFT calculations were performed to rationalize the mechanism and the high efficiency of the phenol‐based phosphonium iodide catalyst. The calculation confirmed the activation of the epoxide via hydrogen bonding for the iodide salt, which facilitates the ring‐opening step. Notably, the effective Gibbs energy barrier regarding this step is 97 kJ mol−1 for the bromide and 72 kJ mol−1 for the iodide salt, which explains the difference in activity.

Synthesis of Alkyl Sulfones from Alkenes and Tosylmethylphosphonium Iodide through Photo-promoted C–C Bond Formation

A new synthetic method for alkyl sulfones through C–C bond formation between alkenes and tosylmethylphosphonium iodide is reported. A tosylmethyl radical is generated from the phosphonium iodide un...

Study on photovoltaic stability and performance by incorporating tetrabutyl phosphonium iodide into the active layer of a perovskite type photovoltaic cell.

A simple synthesis of an ionic liquid is carried out using a trialkylphosphine and an alkyl halide. The results showed that the quality of perovskite crystals is enhanced by the incorporation of B4PI, when the percentage is 1.5% the PCE of champion PSCs MA98.5(B4PI)1.5PbI3 increases significantly from 15.5%, with a VOC of 0.957 mV, JSC of 23.6 mA cm−2, and an FF of 68.4%. Stability tests show that excess B4PI by 20% has a protective effect against humidity, MA80(B4PI)20PbI3 was more stable towards humidity, losing only 20% efficiency for 200 h.

Synthesis and Properties of the Fluoromethylating Agent (Fluoromethyl)triphenylphosphonium Iodide

(Fluoromethyl)triphenylphosphonium iodide has been prepared in a simple and high yield synthesis. The salt was characterized by vibrational, NMR spectroscopy and a single‐crystal X‐ray structure analysis. The salt crystallizes in an orthorhombic space group Pna21 with four formula units in the unit cell. The experimental data are discussed together with quantum chemically calculated values. The title compound is the first example of a phosphonium salt containing a P‐CH2F moiety. Hydrogen bonding in the crystal of the fluoromethyl phosphonium iodide is discussed.

Promotional effect of CH3I on hydroxycarbonylation of cycloalkene using homogeneous rhodium catalysts with PPh3 ligand

The reaction mechanism of the hydroxycarbonylation of cyclohexene with formic acid to form cyclohexanecarboxylic acid using organorhodium complexes was investigated both experimentally and computationally. It was found that excess CH3I and PPh3 promote this reaction. The active catalyst species was determined to be a five-coordinated rhodium hydride 16-electron complex derived from a mononuclear rhodium 16-electron complex (Vaska-type complex). PPh3 and CH3I played the following roles: i) to promote the formation of the Vaska-type Rh complex from Rh2Cl2(CO)4 (1), ii) to aid the elimination of the PPh3 ligand from the Vaska-type complex by stabilizing the free energy of formation of a mononuclear three-coordinated rhodium 14-electron complex through the formation of phosphonium iodide ([Ph3P(CH3)]I), and iii) to generate the active rhodium hydride species.

Синтез и строение гидрата иодида этилтрифенилфосфония [Ph3PEt]I * 0,5H2O

Андреев Павел Валерьевич - ассистент кафедры кристаллографии и экспериментальной физики, Нижегородский государственный университет им. Н.И. Лобачевского. 603950, г. Н. Новгород, пр. Гагарина, 23А. E-mail: andreev@phys.unn.ru Шарутин Владимир Викторович - доктор химических наук, профессор, старший научный сотрудник УНИД, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mai: vvsharutin@rambler.ru. P.V. Andreev1, Andreev@phys.unn.ru V.V. Sharutin2, vvsharutin@rambler.ru O.K. Sharutina2, sharutinao@mail.ru 1 Lobachevsky State University of Nizhni Novgorod, Nizhny Novgorod, Russian Federation 2 South Ural State University, Chelyabinsk, Russian Federation Шарутина Ольга Константиновна - доктор химических наук, профессор, заведующий кфедрой теоретической и прикладной химии, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mai: sharutinao@mail.ru.

Synthesis and identification of copper (II) complexes using phosphonium salt resulting from the combination of trinylphosphine and ethyl bromoacetate, using stereoscopic methods

Phosphonium salts have the general formula and are derived from the sub-ion phosphonium tetrahedral , such as phosphonium iodide . Generally, phosphonium is attributed to an organic derivative, such as tetra-phenyl phosphonium chloride and tetra tetra-methylphosphonium iodide. In this project, the phosphonium compounds [C 2 H 5 COO (CH 2 PPh 3 Br)] and its copper (II) complex [C 2 H 5 COO (CH 2 PP 3 Br)] [Cu 2 Cl 6 ] were prepared and identified. Phosphonium species were prepared from the reaction of ethyl bromoacetate with terphenylphosphine. Then the final compounds were prepared using the reaction between the phosphonium compound with Na 2 [Cu 2 Cl 6 ]. Then, using spectroscopic methods, preparation of these compounds was investigated.

Synthesis and characterization of palladium complexes in combination with Phosphonium salts of 1,3-bis (chloro-methyl)-benzene and benzyl bromide by using stereoscopy methods

Phosphonium salts have the general formula R 4 P + X - and are derived from the sub-ion phosphonium tetrahedral (pH + 4 ) , such as phosphonium iodide[p(CH 3 ) + 4 ] - . Generally, phosphonium is attributed to an organic derivative, such as tetra-phenyl phosphonium chloride and tetra tetra-methyl phosphonium iodide. In this project, phosphonium compounds [C 6 H 5 (CH 2 pph 3 Br)], {C 6 H 4 -1- (CH 2 Cl) -3- (CH 2 pph 3 Cl)} and palladium complexes, [ C 6 H 5 (CH 2 pph 3 )] 2 [pd 2 cl 2 Br 2 ], [C 6 H 4 -1- CH 2 Cl) -3-(CH 2 pph 3 )] 2 [pd 2 Cl 6 ] were prepared and characterized. Phosphonium salts was prepared from the reaction of 1,3-bis (chloro-methyl)- benzene and tri-phenyl phosphine. Then, through the reaction between phosphonium compounds andNa 2 [pd 2 Cl 6 ] final complexes were prepared. Next phosphonium salt was prepared from the reaction between benzyl bromide and tri-phenyl phosphine. Then, final complexes were prepared through a reaction between phosphonium compounds and Na 2 [pd 2 Cl 6 ].

ChemInform Abstract: Design of Bifunctional Quaternary Phosphonium Salt Catalysts for CO2 Fixation Reaction with Epoxides under Mild Conditions.

An efficient synthesis of cyclic carbonates from epoxides and CO2 under mild reaction conditions was achieved via the use of a newly designed bifunctional quaternary phosphonium iodide catalyst. The importance of the bifunctional design of the catalysts was clearly demonstrated in the present work by control experiments. Furthermore, a chiral version of the bifunctional phosphonium salt could be applied to the kinetic resolution of this reaction.

Synthesis and structure of silver complexes [Ph3(i-Pr)P]+ 2[Ag2I4]2− and [Ph3MeP]+ n[Ag3I4]– n

Complexes [Ph3(i-Pr)P]+2[Ag2I4]2- and [Ph3MeP]+n[Ag3I4]–n were synthesized by the reaction of alkyl (triphenyl)phosphonium iodides with silver iodide in dimethyl sulfoxide. Triphenylalkylphosphonium cations have a tetrahedral configuration. Silver atoms in binuclear anions [Ag2I4]2- are characterized by trigonal coordination, the iodine coordination number being 2 or 1. In the polymeric anions [Ag3I4]–n the silver coordination number is 4 and that of iodine, 2, 3, or 4.

Design of bifunctional quaternary phosphonium salt catalysts for CO2 fixation reaction with epoxides under mild conditions

An efficient synthesis of cyclic carbonates from epoxides and CO2 under mild reaction conditions was achieved via the use of a designed bifunctional quaternary phosphonium iodide catalyst.

Fabrication and Properties of Hybrid Thin Film with Epoxy Resin and Methyltrimethoxy Silane-modified ZrO2

The ZrO2-sol was prepared with zirconium acetate and water below 60°C followed by the modification with 0, 0.5 and 5 mol of methyltrimethoxysilane(MTMS) via sol-gel method. The epoxy system was consisted of 1,1,1-(triglycidyl-oxyphenyl) methane, (3-4-epoxycyclohexane) methyl-3-4-epoxycyclohexyl carboxylate, methyl-2,3-norbornanedicarboxylic anhybride, ethyl triphenyl phosphonium iodide and N,N-dimethylacetamide (DMAc). The epoxy system and MTMS-modified ZrO2-sols were mixed to be solid contents of 90 : 10 weight percentages. ZrO2 particles synthesized from sol-gel method were amorphous phase in XRD patterns. FE-SEM images showed MTMS-modified ZrO2 particles were dispersed with excellent homogeneity in hybrid system. The FT-IR spectra of MTMS-modified ZrO2 particle identified the methyl and silica groups formed from MTMS on the surface of ZrO2 particle. It is considered that epoxy-ZrO2 hybrid materials have the potential to be used as the hybrid thin film due to their high refractive index and excellent hybridization stability.

Black-Dye-Based Dye-Sensitized Solar Cells using the Electrolyte Solutions Containing a Quaternary Phosphonium Iodide with a Various Alkyl Chain Length

Solar cell performances of the cosensitized dye-sensitized solar cells (DSCs) with Black dye and D131 using the electrolyte solution containing a quaternary phosphonium iodide with a various alkyl chain length have been evaluated by the photoelectrochemical and the electrochemical impedance spectroscopic measurements. Effects of the difference of the central atom between the quaternary phosphonium iodide and the quaternary ammonium iodide on the solar cell performances have been clarified. The DSC using the electrolyte solution containing tetrabutylphosphonium iodide showed higher Jsc. value and lower Voc and FF values compared to those of the DSC using the electrolyte solution containing tetrabutylammonium iodide. In addition, effects of the alkyl chain length of the quaternary phosphonium iodide on the solar cell performances have been also investigated. The blocking effect of the quaternary phosphonium cation for the access of I3− to the TiO2 surface was found to be improved with increasing the alkyl chain length. The highest conversion efficiency (11.3%) could be obtained in the cosensitized DSC with Black dye and D131 using the electrolyte solution containing a moderate concentration of tetraoctylphosphonium iodide under AM 1.5 (100mW/cm2) irradiation. This study demonstrated that the quaternary phosphonium iodide with a longer alkyl chain is also effective for the improvement of the conversion efficiency of the DSCs due to both the improvement of the electron lifetime in the TiO2 photoelectrode and the slight increment of the conduction band energy of the TiO2.

2-Pyridyl-phosphine and -diphosphine complexes of nickel(0), their reactivity (including aqueous solution chemistry), and some related, incidental methylphosphonium iodides

The chemistry of Ni0-dicarbonyl(pyridylphosphine) complexes of the type Ni(CO)2L2, where L is either P-bonded PPh3−npyn (n=1–3, py=2-pyridyl; abbreviated PNx, x=1–3, species 1a–c), or L2 is (P–P)-chelated py2P(CH2)2Ppy2 or ▪, is further developed from earlier studies by our group [the P–P ligands are abbreviated, respectively, as d(py)pe and d(py)pcp]. The complexes are synthesized from C6H6 solutions of Ni(CO)2(PPh3)2, and the Ni(CO)2(PPh3)(PNx) intermediates (1a∗–c∗) are detected; Ni(CO)2[d(py)pcp] (2b) is shown by X-ray analysis to have a distorted tetrahedral structure; and the NiII species [Ni2(CO)4(μ-PN2)2]Cl4 is isolated from a light-induced reaction in CDCl3 solution. Complex 2b dissolves in water at ambient conditions via a net double protonation of pyridyl N-atoms, the {Ni(CO)2[2H-d(py)pcp]}2+ being isolated as the bis(triflate) salt; the dication decomposes in minutes with formation of [Ni(H2O)6]2+, CO, the phosphine dioxide, and deprotonated d(py)pcp. Some twenty-two Ni0 complexes, exemplified by Ni(P–P)2, Ni(PNx)2(P–P), Ni(PNx)4, and related PPh3- and Ph2P(CH2)2PPh2 (dppe)-containing species, are synthesized from Ni(1,5-COD)2 and their reactivity studied; for example, oxidative addition of MeI generates trans-Ni(Me)(I)(PN3)2 and trans-Ni(Me)(I)(P–P)2 but, with non-pyridyl containing reactants such as Ni(PPh3)4 and Ni(dppe)2, only (monomethyl)phosphonium iodides are formed. Such iodides, and the bis(methyl) analogues [(CH3)2(diphosphine)]I2, are then studied for clarification of some observed Ni chemistry. The NMR trends (a)–(d) are noted within the series of Ni0 complexes, and are rationalized: (a) the 2JPP values in 1a∗–c∗, and the separation between the two doublets, parallel the number of N-atoms present; (b) the 31P{1H} signals in the Ni(PNx)4 and Ni(PNx)2(P–P) complexes shift downfield in the order PN1<PN2<PN3 within linear dependences; (c) the 2JPP values for the Ni(PR3)2(P–P) complexes (R=Ph and PNx) decrease in the order R=Ph>PN1>PN2>PN3; (d) and the separation between the two 31P{1H} triplets of the Ni(PNx)2(P–P) complexes generally depends on the relative numbers of phenyl and pyridyl groups.