Antimony pentachloride catalyst

Chlorofluorocarbons (CFCs) are manufactured by reacting hydrogen fluoride and carbon tetrachloride in the presence of a partially fluorinated antimony pentachloride catalyst in a continuous, liquid-phase process. 

In the process (Fig. 1), anhydrous hydrogen fluoride and carbon tetrachloride (or chloroform) are bubbled through molten antimony pentachloride catalyst in a steam-jacketed atmospheric pressure reactor at 65 to 95°C. The gaseous mixture of fluorocarbon and unreacted chlorocarbon is distilled to separate and recycle the chlorocarbon to the reaction. Waste hydrogen chloride is recycled by use of water absorption and the last traces of hydrogen chloride and chlorine are removed in a caustic scrubbing tower. 

Another example is a copolymer of allylglycidyl ether with tetrahydrofuran formed with antimony pentachloride catalyst. ... 

Other catalysts which may be used in the Friedel - Crafts alkylation reaction include ferric chloride, antimony pentachloride, zirconium tetrachloride, boron trifluoride, zinc chloride and hydrogen fluoride but these are generally not so effective in academic laboratories. The alkylating agents include alkyl halides, alcohols and olefines. 

Ben2enesulfonic anhydride has been claimed to be superior to ben2enesulfonyl chloride (140). Catalysts used besides aluminum chloride are ferric chloride, antimony pentachloride, aluminum bromide, and boron trifluoride (141). 

Dichloroethane is produced by the vapor- (28) or Hquid-phase chlorination of ethylene. Most Hquid-phase processes use small amounts of ferric chloride as the catalyst. Other catalysts claimed in the patent Hterature include aluminum chloride, antimony pentachloride, and cupric chloride and an ammonium, alkaU, or alkaline-earth tetrachloroferrate (29). The chlorination is carried out at 40—50°C with 5% air or other free-radical inhibitors (30) added to prevent substitution chlorination of the product. Selectivities under these conditions are nearly stoichiometric to the desired product. The exothermic heat of reaction vapori2es the 1,2-dichloroethane product, which is purified by distillation. 

Carbon tetrachloride is used to produce chlorofluorocarbons by the reaction with hydrogen fluoride using an antimony pentachloride (SbCls) catalyst ... 

With gallium chloride, ferric chloride and antimony pentachloride the rate coefficients were dependent upon the concentration of chlorobenzene and the square of the concentration of the catalyst, but the third-order coefficients varied with the initial concentration of the catalyst (Table 103)394. The overall kinetic equation was, therefore,... 

Antimony pentachloride is used as a catalyst in organic synthesis. 

Carbon tetrachloride is made by the reaction of carbon disulfide and chlorine in the presence of a catalyst, such as iron or antimony pentachloride ... 

The UDRI synthesis began by reacting benzocyclobutene with 4-nitroben-zoyl chloride 108 in the presence of a stoichiometric amount of the Lewis Acid, antimony pentachloride, at low temperature. The route pursued by Dow researchers utilized higher temperatures and 1 mole % of ferric oxide as the catalyst (Fig. 45) [46, 47, 102],... 

Cationic mechanisms are much more characteristic of the polymerization of oxygen heterocycles, both ethers and acetals. A wide variety of catalysts has been used, including protonic acids, such Lewis acids as boron trifluoride, phosphorus pentafluoride, stannic chloride, antimony pentachloride, titanium tetrachloride, zinc chloride, and ferric chloride, and salts of carbocations or tri-alkyloxonium ions having anions derived from Lewis acids. Some complex, coordination catalysts that appear to operate by a mechanism... 

Several catalysts and initiator systems have been tested for the polymerization of GlcAnBzl3, including the following Lewis acids boron trifluoride and its etherate, phosphorus pentafluoride, titanium tetrachloride, and antimony pentachloride and pentafluoride. Several cationic initiators have also been used, including (triphenylmethyl) antimony hexachloride, 2,3,4,6-tetra-O-acetyl-D-glucopyranosyl hexa-fluorophosphate, acetyl hexafluorophosphate, pentamethylbenzyl hexa-fluorophosphate (most of which were generated in situ), and triethyl-... 

The oxidation of propane into acrylic acid in the presence of heteropoly catalysts prepared from H3PM012O40 and antimony pentachloride gave rather low conversion and selectivity [10 and 19%, respectively (2% yield)] (352). Recently, a yield of ca. 9% was obtained with H5PV2M010O40 (353). The addition of Cr ion also enhanced the catalytic performance (354). 

Meerwein applied the oxonium salts to the polymerization of the tetrahydrofurans and found them effective catalysts (6, 7,8). The boron fluoride and antimony pentachloride derivatives gave significantly faster rates than did those from ferric and aluminum chlorides but all produced polymer at low temperature (—10° to + 40°) and at low catalyst concentration (0.1 to 2 mol percent of the monomer). On the... 

The importance of acyl cations in acetylation is indicated in several studies (Gore, 1955). Friedel-Crafts catalysts alter the rate of acylation but do not modify the selectivity of the reaction. For example, the antimony pentachloride-catalyzed benzoylation of toluene proceeds 1.3 x 103 more rapidly than the aluminum chloride-catalyzed reaction. 

Fluorocarbons are made from chlorinated hydrocarbons by reacting them with anhydrous hydrogen fluoride, using an antimony pentachloride (SbCl5) catalyst. 

Depending on the substituents in (61) and on the concentration of the catalyst, however, other products may also subsequently be formed. In some cases, SbCl5-complexed primary intermediates of type (65) could even be isolated and characterized by NMR spectroscopy as well as by well-defined chemical reactions (81JA1789). Treatment of tetraphenyl-1,2,4-trioxolane (67) with antimony pentachloride or liquid sulfur dioxide, a mild Lewis acid, gave benzophenone and phenyl benzoate in a molar ratio of 1 1 (80JA288). The formation of the ester corresponds to that of the carboxylic acid from (61) via path A or path B. 

The catalyst for the first set of reactions (3.2) was a mixture of antimony pentachloride and titanium tetrachloride. These sequences may involve addition-elimination reactions, as well as nucleophilic substitution. 

Initiation of polyalkene cyclization by an acid chloride and termination by an alkenylsilane have been combined in a synthesis of an octahydronaphthalene as part of studies towaids the synthesis of dihydro-compactin, where the silane can be viewed as controlling the Friedel-Crafts acylation of the disubstituted double bond (equation 10). In this case, antimony pentachloride gave superior yields compared to a wide variety of commonly used Lewis acid catalysts. 

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