55818-45-6Relevant academic research and scientific papers
Aluminum triflate as a highly active and efficient nonprotic cocatalyst in the palladium-catalyzed methoxycarbonylation reaction
Williams, D. Bradley G.,Shaw, Megan L.,Green, Michael J.,Holzapfel, Cedric W.
, p. 560 - 563 (2008)
(Chemical Equation Presented) Lewis does it better: Aluminum triflate readily replaces Bronsted acid cocatalysts in the palladium-catalyzed methoxycarbonylation reaction of styrene and 1-pentene, producing catalysts that are stable and more active than those using traditional acids. Catalyst loadings of 0.02% allow conversions of up to 100% to be achieved within three hours with no loss of linear/branched ester selectivity.
Quaternary phosphonium salt flame retardant and synthesis method and application thereof
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Paragraph 0061-0072, (2020/06/20)
The invention provides a quaternary phosphonium salt flame retardant and a synthesis method and application thereof, and the method comprises the following steps: by taking an acidic compound, ortho-formic acid trisubstituted ester and an organic phosphine compound III or IV as raw materials, carrying out a one-step reaction process to prepare the quaternary phosphonium salt flame retardant I or II. The flame retardant disclosed by the invention has good thermal stability and has an excellent flame-retardant effect when being applied to various polymers. The method is simple and convenient insynthesis operation, low in raw material price, mild in synthesis condition and high in yield. According to the synthesis method, introduction of halogen ions is avoided, and dozens of anions are successfully introduced. By adding a small amount of the flame retardant, the obtained PC flame-retardant composite material UL-94 can reach the V-0 grade.
Practical synthesis of phosphonium salts with orthoformates and their application as flame retardants in polycarbonate
Jiang, Pingkai,Li, Tao,Xu, Chencong,Zhang, Yong Jian
, (2020/03/23)
An efficient and practical approach to phosphonium salts has been developed. By the reaction of phosphines and different acid sources with orthoformates in one-step operation, the process allowed rapid access to phosphonium salts with diverse counterions in high yield after the purification by recrystallization. The flame retardant performance in PC has also been examined by blending several phosphonium salts to PC respectively. Phosphonium phosphates showed excellent flame retardancy in PC with only 2 phr blending.
Methyltriarylphosphonium Arenesulfonates. Preparation and Characterization by 1H, 31P, and 17O FTNMR, Cyclic Voltammetry, and Molecular Orbital Calculations
Bugner, D. E.
, p. 2580 - 2586 (2007/10/02)
Two series of methyltriarylphosphonium arenesulfonates (1a-i, 2a-g) were prepared in which either the anion or the cation is systematically varied.The frontier molecular orbitals of these salts were evaluated by a combination of spectroscopic, electrochemical, and theoretical techniques.For the cation variations, irreversible reductions are observed by cyclic voltammetry, which correlate well with substituent electronegativities. 1H NMR (for the P-methyl group) and 31P NMR (for the phosphorus itself) data also correlate well with substituent constants.For the anion variations, irreversible oxidations are observed which correlate better with ? than with ?0, implying that the aromatic ?-system is involved in the oxidation. 17O NMR chemical shifts for the sulfonate group, on the other hand, yield a better correlation with ?0, as would be expected for a purely inductive effect.Semiempirical molecular orbital calculations at the AM1 level were also performed on both series of ions.The calculations are consistent with the expectation that, for a given phosphonium sulfonate salt, the LUMO is on the cation and the HOMO is on the anion.Both HOMO and LUMO energies exhibit very good linear correlations with substituent constants.While the LUMO energies also correlate well with the cathodic peak potentials, the HOMO energies give a substantially poorer correlation with the anodic peak potentials.However, by using the energies calculated for the highest occupied ?-orbitals (HOPO's) for the anions, a much improved correlation is observed.This is also consistent with the removal of an electron from the aromatic ?-system rather than the charge-bearing sulfonate group.
