363-72-4Relevant articles and documents
Deacon, G. B.,Parrott, J. C.
, p. 11 - 23 (1968)
The fluorine-pentafluorophenyl substitution reaction in anhydrous hydrogen fluoride (aHF): A new interesting methodical approach to synthesize pentafluorophenylxenonium salts
Frohn, Hermann-Josef,Schroer, Thorsten
, p. 259 - 264 (2001)
In anhydrous hydrogen fluoride (aHF) (heterogeneous reaction) B(C6F5)3 transfers all the three aryl groups to XeF2 forming [C6F5Xe]+ salts. Upon addition of KF, the [C6F5Xe] [HF2] salt was isolated in 78.7% yield. [C6F5Xe] [HF2] dissolved in MeCN exhibits significant cation-anion interactions and decomposes within 14 days at 20°C. The acidity of the aHF solvent determines the nature of the products in the reaction of XeF2 with B(C6F5)3. The reaction path of this new methodical approach of fluorine-aryl substitution in aHF is discussed.
Promotion of reductive elimination reaction of diorgano(2,2′-bipyridyl)nickel(II) complexes by electron-accepting aromatic compounds, Lewis acids, and Bronsted acids
Yamamoto, Takakazu,Abla, Mahmut,Murakami, Yasuharu
, p. 1997 - 2009 (2002)
Reductive elimination of R-R from dialkyl(2,2′-bipyridyl)nickel(II), [NiR2(bpy)] 1 (R = CH3 (1a), C2H5 (1b), n- C3H7 (1c)), caused by π-coordination of electron-accepting aromatic compounds and reductive elimination of Ar-Ar from [NiAr2(bpy)] 2 (Ar = C6F5 (2a) and pyrazolyls (2b and 2c)) promoted by electron-accepting aromatic compounds, Lewis acids, and Bronsted acids have been investigated. 1H-NMR and kinetic data indicate that π-coordination of the electron-accepting aromatic compound to [NiR2(bpy)] leads to the reductive elimination of R-R. The rate of the reductive elimination obeys the second-order rate law, -d[1]/dt = k[1][electron-accepting aromatic compound]. Plots of log k vs Σσp of the electron-accepting aromatic compound give a line with a slope of 1.8. Bronsted acids cause reductive elimination of Ar-Ar from 2 selectively under several reaction conditions (e.g., 2a with CF3COOH in air and 2b with HBr). The reductive elimination reaction of 2a caused by CF3COOH obeys the second-order rate law, -d[2a]/dt = k′[2a][CF3COOH], in air. The reaction of 2b with H2SO4 requires O2, giving the rate equation, -d[2b]/dt = k″[2b]2[O2]; k″ increases with [H2SO4], reaching a maximum value at a high [H2SO4]. UV-vis spectroscopy reveals the presence of the following equilibrium: 2b + H2SO4 ? 2b·H2SO4, and the equilibrium constant Ka is evaluated as Ka = [2b·H2SO4]/ ([2b][H2SO4]) = 47 M-1 at 300.5 K. UV-vis data give information about the electronic states of 2 and the 2b-Bronsted acid adduct. Poly(6-hexylpyridine-2,5-diyl) with a higher molecular weight has been prepared according to the basic information.
Promoting Difficult Carbon–Carbon Couplings: Which Ligand Does Best?
Gioria, Estefanía,del Pozo, Juan,Martínez-Ilarduya, Jesús M.,Espinet, Pablo
, p. 13276 - 13280 (2016)
A Pd complex, cis-[Pd(C6F5)2(THF)2] (1), is proposed as a useful touchstone for direct and simple experimental measurement of the relative ability of ancillary ligands to induce C?C coupling. Interestingly, 1 is also a good alternative to other precatalysts used to produce Pd0L. Complex 1 ranks the coupling ability of some popular ligands in the order PtBu3>o-TolPEWO-F≈tBuXPhos>P(C6F5)3≈PhPEWO-F>P(o-Tol)3≈THF≈tBuBrettPhos?Xantphos≈PhPEWO-H?PPh3according to their initial coupling rates, whereas their efficiency, depending on competitive hydrolysis, is ranked tBuXPhos≈PtBu3≈o-TolPEWO-F>PhPEWO-F>P(C6F5)3?tBuBrettPhos>THF≈P(o-Tol)3>Xantphos>PhPEWO-H?PPh3. This “meter” also detects some other possible virtues or complications of ligands such as tBuXPhos or tBuBrettPhos.
Reaction of difluoromethyl pentafluorophenyl sulfoxide with nucleophiles
Koshcheev,Maksimov,Platonov,Shelkovnikov
, (2017)
Reactions of 1-(difluoromethanesulfinyl)pentafluorobenzene with sodium methoxide, sodium phenoxide, potassium hydrosulfide, and methylamine resulted in substitution of fluorine atom in the 4-position (in the reaction with methylamine, also in the 2-positi
Deacon, G. B.,Raverty, W. D.,Vince, D. G.
, p. 103 - 114 (1977)
Grignard exchange reaction using a microflow system: From bench to pilot plant
Wakami, Hideo,Yoshida, Jun-Ichi
, p. 787 - 791 (2005)
The Grignard exchange reaction of ethylmagnesium bromide (EtMgBr) and bromopentafluorobenzene (BPFB) to give pentafluorophenylmagnesium bromide (PFPMgBr) was carried out using small- and medium-scale microflow systems consisting of a micromixer and a microheat exchanger. The results indicate that the microflow systems are quite effective. On the basis of the data obtained, a pilot that involves the Toray Hi-mixer connected to a shell and tube microheat exchanger was constructed. Continuous operation for 24 h was accomplished without any problem to obtain pentafluorobenzene (PFB) after protonation (92% yield).
Reductive elimination of C6F5-C6F 5 in the reaction of bis(pentafluorophenyl)palladium(ii) complexes with protic acids
Koizumi, Take-Aki,Yamazaki, Atsuko,Yamamoto, Takakazu
, p. 3949 - 3952 (2008)
Reductive elimination of C6F5-C6F 5 from cis-[Pd(C6F5)2L] (L = cod, bpy, and dppb) was promoted by Bronsted acids. HNO3 is a convenient acid for the formation of C6F5-C 6F5 from [Pd(C6F5) 2(cod)]. The products are controlled by the auxiliary ligand.
Photoredox catalysis on unactivated substrates with strongly reducing iridium photosensitizers
Shon, Jong-Hwa,Kim, Dooyoung,Rathnayake, Manjula D.,Sittel, Steven,Weaver, Jimmie,Teets, Thomas S.
, p. 4069 - 4078 (2021/04/06)
Photoredox catalysis has emerged as a powerful strategy in synthetic organic chemistry, but substrates that are difficult to reduce either require complex reaction conditions or are not amenable at all to photoredox transformations. In this work, we show that strong bis-cyclometalated iridium photoreductants with electron-rich β-diketiminate (NacNac) ancillary ligands enable high-yielding photoredox transformations of challenging substrates with very simple reaction conditions that require only a single sacrificial reagent. Using blue or green visible-light activation we demonstrate a variety of reactions, which include hydrodehalogenation, cyclization, intramolecular radical addition, and prenylationviaradical-mediated pathways, with optimized conditions that only require the photocatalyst and a sacrificial reductant/hydrogen atom donor. Many of these reactions involve organobromide and organochloride substrates which in the past have had limited utility in photoredox catalysis. This work paves the way for the continued expansion of the substrate scope in photoredox catalysis.
Catalytic Hydrodefluorination via Oxidative Addition, Ligand Metathesis, and Reductive Elimination at Bi(I)/Bi(III) Centers
Cornella, Josep,Katzenburg, Felix,Leutzsch, Markus,N?thling, Nils,Pang, Yue
supporting information, p. 12487 - 12493 (2021/08/30)
Herein, we report a hydrodefluorination reaction of polyfluoroarenes catalyzed by bismuthinidenes, Phebox-Bi(I) and OMe-Phebox-Bi(I). Mechanistic studies on the elementary steps support a Bi(I)/Bi(III) redox cycle that comprises C(sp2)-F oxidative addition, F/H ligand metathesis, and C(sp2)-H reductive elimination. Isolation and characterization of a cationic Phebox-Bi(III)(4-tetrafluoropyridyl) triflate manifests the feasible oxidative addition of Phebox-Bi(I) into the C(sp2)-F bond. Spectroscopic evidence was provided for the formation of a transient Phebox-Bi(III)(4-tetrafluoropyridyl) hydride during catalysis, which decomposes at low temperature to afford the corresponding C(sp2)-H bond while regenerating the propagating Phebox-Bi(I). This protocol represents a distinct catalytic example where a main-group center performs three elementary organometallic steps in a low-valent redox manifold.