Hydrogen fluoride-Boron trifluoride

The cr-complexes (iv) are thus the intermediates corresponding to the substitution process of hydrogen exchange. Those for some other substitutions have also been isolated in particular, benzylidyne trifluoride reacts with nitryl fluoride and boron trifluoride at — ioo°C to give a yellow complex. Above — 50 °C the latter decomposes to hydrogen fluoride, boron trifluoride, and an almost quantitative yield of tn-nitrobenzylidyne trifluoride. The latter is the normal product of nitrating benzylidyne trifluoride, and the complex is formulated as... 

Continuous-Flow Stirred-Tank Reactors. The synthesis of j )-tolualdehyde from toluene and carbon monoxide has been carried out using CSTR equipment (81). -Tolualdehyde (PTAL) is an intermediate in the manufacture of terephthabc acid. Hydrogen fluoride—boron trifluoride catalyzes the carbonylation of toluene to PTAL. In the industrial process, separate stirred tanks are used for each process step. Toluene and recycle HF and BF ... 

McCaulay, D., Shoemaker, B., and lien, A. (1950) Hydrogen fluoride-boron trifluoride extraction of xylene isomers. Ind. Eng. Chem., 42 (10), 2103-2107. 

Numerous Lewis acids promote the formation of nitronium ions when in the presence of nitric acid. Nitric acid-boron trifluoride, and the nitric acid-hydrogen fluoride-boron trifluoride reagents described by Olah are practical nitrating agents the latter provides a convenient preparation of nitronium tetrafluoroborate. Olah reports that nitric acid-magic acid (FSOsH-SbFs) is extremely effective for the polynitration of aromatic substrates. 

However, it should be pointed out that the combination of iodochloride/hydrogen fluoride/ boron trifluoride is only efficient for the iodofluorination of terminal alkenes no corresponding iodide could be detected in reactions with perfluoropent-2-ene, even on prolonged heating (16 h) at 200 °C.341... 

The action of strong aprotic Lewis acids (antimony(V) fluoride, arsenic(V) fluoride etc.) provokes the ionization of xenon difluoride, leading to the formation of fluoroxenonium salts XcF + MFn or Xe2F3 MFn less strong acceptors of the fluoride ion (hydrogen fluoride, boron trifluoride, etc.) polarize the xenon difluoride molecule. 

The hydrogen fluoride catalyzed fluorination of norbornene by xenon difluoride at room temperature leads to a mixture of at least seven components,39 but under milder conditions (— 78 to 26 C, 22 hours) the reaction affords a mixture of two main products 2-e,xo-5-cxo-difluoro-norbornane and 2-c-wfo-5- Yo-difluoronorbornane, ratio 2 1, in a total yield of 51-76%. If the same reaction is carried out in a limited temperature range between — 46 and — 39 C the yield of these products decreases, their ratio becomes equal, and the main product is 2-exo-l-ff //-difluoronorbornane (42 %).40 The structure dependence of the fluorination products of norbornene with xenon difluoride was studied. Solvent, temperature, reaction duration, catalyst (hydrogen fluoride, boron trifluoride, trifluoroacetic acid, pentafluorobenzenethiol) and the routes of product isomerization were analyzed.41-42... 

The addition of chlorine monofluoridc across the C = 0 bonds in difluorophosgene, per-fluoroacyl fluorides, and perfluoroketones with the formation of hypochlorites occurs only in the presence of the catalysts potassium fluoride, rubidium fluoride, cesium fluoride80,81 or the strong Lewis acids hydrogen fluoride, boron trifluoride, or arsenic(V) fluoride.82 The cesium fluoride catalyzed reactions are carried out in an autoclave for 2-3 hours at — 20"C or left overnight.80... 

Nitrosonium tetrafluoroborate (1) is a white powder made from hydrogen fluoride, boron trifluoride and nitrogen dioxide. 

A review of formylation reactions involving methyl formate in a hydrogen fluoride-boron trifluoride medium has appeared.60 Regioselectivity and kinetic data have been reported for Gattermann-Koch formylation in superacids and provide evidence for an intra-complex reaction where the formylation electrophile HCO+ is generated by protonation of CO by the arenium ion.61 The observed selectivity results from... 

Hydrogen Fluoride-Boron Trifluoride (Tetrafluoroboric Acid). 

Hydrogen peroxide-Hydrogen fluoride/Boron trifluoride etherate. 

HYDROXYLATION, ARENES Hydrogen peroxide-Hydrogen fluoride-Boron trifluoride etherate. Potassium superoxide. 

Treatment of a, -epoxy sulfoxides with tw O equivalents of potassium hydrogen fluoride/ boron trifluoride-diethyl ether complex reagent in chloroform at room temperature gives a-fluoro ketones in moderate to good yield together with some rearranged products.There are no other examples of the use of this reagent. 

The source of chlorine is most often chlorine, hexachloromelamine, /V-chlorosuccinimide or tert-butyl hypochlorite. The fluoride source is usually hydrogen fluoride, boron trifluoride or, recently, silver(I) fluoride. Chlorine fluoride can also undergo addition to alkenes when chlorine monofluoride or chlorine trifluoride or a mixture of both is employed. ... 

We used for the further tests the system hydrogen fluoride/ boron trifluoride as catalyst and olefins as means of alkylation. 

ACIDS, INORGANIC Boric acid. Chloro-Iridic acid. Hydrobtomic acid. Hydrochloric acid. Hydrogen bromide. Hydrogen chloride. Hydrogen fluoride. Hydrogen fluoride-Boron trifluoride. ion-exchange resins. Nitric acid. Periodic acid. Phosphoric acid. Folyphosphoric acid. Sulfuric acid. 

ISOMERIZATION Potassium (-butoxlde. ACETYLENES AND ALLENES Hydrogen fluoride-Boron trifluoride. 

Hydrogen bromide, 26, 250 Hydrogen chloride, 26, 252 Hydrogen cyanide, 155, 252,334, 538 Hydrogen fluoride, 26,46,165, 252 Hydrogen fluoride-Boron trifluoride, 252-253... 

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