16524-41-7Relevant academic research and scientific papers
Cyclic analogues of the Hendrickson 'POP' reagent
Elson, Kathryn E.,Jenkins, Ian D.,Loughlin, Wendy A.
, p. 371 - 376 (2004)
The Hendrickson reagent, triphenylphosphonium anhydride trifluoromethanesulfonate, 'POP' 1, is a powerful dehydrating agent. Five-, six-, and seven-membered cyclic analogues of the 'POP' reagent 2-4 have been prepared and their use for ester and amide synthesis investigated. A kinetic comparison of the cyclic analogues 2-4 revealed that a considerable increase in the rate of esterification could be achieved when the five-membered ring analogue 2 was used, presumably due to the ease of formation of the putative phosphorane intermediate. The rate of ester formation from a primary alcohol using the Hendrickson reagent 1 was shown to be significantly faster when non-polar solvents were employed.
31P NMR spectroscopic analysis on photooxidation of 1,n-bis(diphenylphosphino)alkanes with the aid of DFT calculations
Yasui, Shinro,Yamazaki, Shoko
, (2020)
The chloroform-d solution of diphosphine, 1,n-bis(diphenylphosphino)alkane (Ph2P(CH2)nPPh2; n = 1-6), was photolyzed with light from a xenon lamp in air. The progress of the reaction was followed by 31P NMR spectroscopy. The observed spectral change showed that the diphosphine is initially oxidized to diphosphine monoxide, Ph2P(═O)(CH2)nPPh2, which is further oxidized to diphosphine dioxide, Ph2P(═O)(CH2)nP(═O)Ph2. The oxidation of the diphosphine to the diphosphine monoxide took place according to first-order kinetics with respect to the concentration of the diphosphine, the first-order rate constant, kobs, being larger with increasing number of the methylene units in the spacer. The observation in kinetics is interpreted based on the conformation of the diphosphine radical cation intermediate initially generated by electron transfer from the photoexcited diphosphine to oxygen. Density functional theory (DFT) calculations predict that the diphosphine radical cation takes “folded” conformation where two phosphorus atoms are arranged closely to each other. The “folded” conformer of the diphosphine radical cation results from electrostatic interaction of these two phosphorus atoms. This conformer explains the observed dependency of kobs on the length of the spacer in the diphosphine.
Intramolecular stabilization of the phosphine radical cation by the second phosphorus atom during the photooxidation of diphosphines:31P NMR spectroscopic analysis
Yasui, Shinro,Yamazaki, Shoko
, p. 422 - 424 (2015)
Diphosphines, Ph2P(CH2)nPPh2 1 (n = 1, 2, 3, 4, and 6), were photolyzed by a xenon lamp in air. The 31P NMR spectroscopic analysis of the reaction showed that 1 is oxidized, according to first-order kinetics, to the monoxide, which is further oxidized to the dioxide. The dependence of the rate constants for the first oxidation on the chain-length n in 1 is interpreted in terms of the orientation of the p-orbitals on the two phosphorus atoms in the intermediate, the diphosphine radical cation.
Synthesis of novel phosphonium betaines and bis-betaines derived from hexafluoro-1,4-naphthoquinone
Zhivetyeva,Tretyakov,Bagryanskaya, I.Yu.
, p. 19 - 28 (2018)
Reactions of hexafluoro-1,4-naphthoquinone with phosphorus-centered bis-phenylphosphanes with structure Ph2P(CH2)nPPh2 (where n = 1–5) and Et2P(CH2)2PEt2 in various solvents (anhydrous C6H6, aq. C6H6, aq. dioxane, aq. DMSO, or MeOH) were investigated. It was shown that the use of aqueous dioxane and DMSO leads to target products of phosphanodefluorination (i.e., phosphorus-containing betaines and bis-betaines) with high yields. We found that the betaines upon purification by thin-layer chromatography underwent various transformations such as a ring contraction (thus yielding novel polyfluorinated indenones) or addition of an acetone molecule at the C[dbnd]O bond of the fluorinated 1,4-naphthoquinone. According to X-ray diffraction analysis, there were intermolecular F?π interactions in the crystal packing of all the obtained betaines. The interactions are characterized by short distances F?Cg from 3.151(5) to 3.831(2) ? (where Cg is a centroid of π-system).
Selective synthesis and stabilization of peroxides: Via phosphine oxides
Arp, Fabian F.,Ahn, Shin Hye,Bhuvanesh, Nattamai,Blümel, Janet
, p. 17174 - 17181 (2019)
Reaction of bis(dicyclohexylphosphino)ethane dioxide with hydrogen peroxide leads to an extended crystalline network based on the formation of hydrogen bonds with the PO groups of the diphosphine dioxide. The structural motif of the network is characterized by X-ray diffraction. A new selective synthesis for an industrially important MEKPO (methyl ethyl ketone peroxide) dimer is described. The dimer is created by reaction of dppe dioxide (bis(diphenylphosphino)ethane dioxide) with butanone and hydrogen peroxide. This peroxide is stabilized by forming strong hydrogen bonds to the phosphine oxide groups within an extended network, which has been characterized by single crystal X-ray diffraction. Reaction of acetylacetone with hydrogen peroxide, irrespective of the presence of phosphine oxide, leads to the stereoselective formation of two dioxolanes. Both cyclic peroxides have been obtained in crystalline forms suitable for single crystal X-ray diffractions.
Compound containing bis-diphenyl phosphinic oxygen structure and preparation method thereof
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Paragraph 0039-0040, (2021/04/21)
The invention discloses a compound containing a bis-diphenyl phosphinic oxygen structure and a preparation method of the compound, and belongs to the technical field of organic synthesis. In a polar solvent, diphenyl phosphorus chloride or diphenyl phosph
Evaluation of bifunctional chiral phosphine oxide catalysts for the asymmetric hydrosilylation of ketimines
Warner, Christopher J.A.,Berry, Sian S.,Jones, Simon
, (2019/11/11)
A series of bifunctional phosphine oxides have been prepared and evaluated as catalysts for the trichlorosilane mediated asymmetric hydrosilylation of ketimines. bis-Phosphine oxides, hydroxy-phosphine oxides, and biaryl phosphine oxides all demonstrated good catalytic activity, but poor to moderate enantioselectivity. A bis-P-chiral phosphine oxide displayed the highest enantioselectivity of 60%.
Dearylation of arylphosphine oxides using a sodium hydride-iodide composite
Tejo, Ciputra,Pang, Jia Hao,Ong, Derek Yiren,Oi, Miku,Uchiyama, Masanobu,Takita, Ryo,Chiba, Shunsuke
supporting information, p. 1782 - 1785 (2018/02/21)
A new protocol for the dearylation of arylphosphine oxides was developed using sodium hydride (NaH) in the presence of lithium iodide (LiI). The transient sodium phosphinite could be functionalized with a range of electrophiles in a one-pot fashion.
Bidentate Phosphine-Assisted Synthesis of an All-Alkynyl-Protected Ag74 Nanocluster
Qu, Mei,Li, Huan,Xie, Lin-Hua,Yan, Shuai-Ting,Li, Jian-Rong,Wang, Jun-Hao,Wei, Cai-Yun,Wu, Yu-Wei,Zhang, Xian-Ming
supporting information, p. 12346 - 12349 (2017/09/23)
Determining the total structure of metal nanoparticles is vital to understand their properties. In this work, the first all-alkynyl-protected Ag nanocluster, Ag74(C≡CPh)44, was synthesized and structurally characterized by single cry
Direct conversion of phosphonates to phosphine oxides: An improved synthetic route to phosphines including the first synthesis of methyl JohnPhos
Kendall, Alexander J.,Salazar, Chase A.,Martino, Patrick F.,Tyler, David R.
supporting information, p. 6171 - 6178 (2015/02/19)
The synthesis of tertiary phosphine oxides from phosphonates was achieved reliably and in good to excellent yields using stoichiometric amounts of alkyl or aryl Grignard reagents and sodium trifluoromethanesulfonate (NaOTf). In the absence of the NaOTf additive, covalent coordination oligomers of magnesium and phosphorus species dominate the reaction, producing very low yields of phosphine oxide, but high conversions of the phosphonate starting material. Mechanistic studies revealed that a five-coordinate phosphorus species - not a phosphinate - is the reaction intermediate. A diverse array of phosphonates was converted to phosphine oxides using a variety of Grignard reagents for direct carbon-phosphorus functionalization. This new methodology especially simplifies the synthesis of dimethylphosphino (RPMe2)-type phosphines by using air-, water-, and silica-stable intermediates. To highlight this reaction, a new Buchwald-type ligand ([1,1′-biphenyl]-2-yldimethylphosphine, or methyl JohnPhos) and a classic bidentate phosphine, bis(diphenylphosphino)propane (dppp), were synthesized in excellent yields.
