Hydrogen fluoride with anhydrides

Derivation Reaction of anhydrous hydrogen fluoride with sulfuric acid or sulfuric acid anhydride. 

Ben zotricbl oride is hydrolyzed to benzoic acid by hot water, concentrated sulfuric acid, or dilute aqueous alkaH. Benzoyl chloride [98-88-4] is produced by the reaction of benzotrichloride with an equimolar amount of water or an equivalent of benzoic acid. The reaction is catalyzed by Lewis acids such as ferric chloride and zinc chloride (25). Reaction of benzotrichloride with other organic acids or with anhydrides yields mixtures of benzoyl chloride and the acid chloride derived from the acid or anhydride (26). Benzo triflu oride [98-08-8] is formed by the reaction of benzotrichloride with anhydrous hydrogen fluoride under both Hquid- and vapor-phase reaction conditions. 

Naphthalene-1,8-dicarboxylic add, its nitro-substituted derivatives, and naphthalene-1,4,5,8 tetracarboxylic acid, on treatment with sulfur tetrafluoride at 0 C, undergo dehydration to form quantitatively the corresponding anhydrides [218, 221] Unsubstituted and mononitrated monoanhydndes react further at 200-250 °C to give derivatives of 1,1,3,3-tetrafluoro-l// naphtho[I,8 c,d]pyran Dinitronaphthalene-l,8-di-carboxyhc acid anhydndes and naphthalene 1,4,5,8 tetracarboxylic acid dianhydnde give the respective tetra- and octafluoroethers only in the presence of an excess of anhydrous hydrogen fluoride [221] (equabons 113 and 114)... 

Benzoyl fluoride can also be prepared by the reaction of anhydrous hydrogen fluoride or potassium fluoride with benzoic anhydride and by the halogen exchange of benzoyl chloride with alkali fluorides, such as NaF/ KF/ KHF2, Na2SiFe, or various other metal fluorides. ... 

A convenient method for the preparation of nitronium tetrafluoroborate involves treating a mixture of absolute nitric acid or an alkyl nitrate " with anhydrous hydrogen fluoride and an excess of boron trifluoride. Pure nitronium triflate can be synthesized by treating triflic anhydride or triflic acid with dinitrogen pentoxide in an inert solvent. Other methods for nitronium salt synthesis are discussed by Olah. ... 

As hydrogen fluoride functions with equal ease in alkylation with olefins, alkyl halides, or alcohols, and in acylation with acids, acid anhydrides as well as acyl halides, a wide choice of reagents is possible and a separate operation of the reconversion of them is often saved. With aluminum chloride the alkyl halides and acyl halides are the preferred reagents and frequently must be made from more plentiful, cheaper, and readily available substances. 

Fluorination of tetrachlorophthalic acid with sulfur tetrafluoride alone or of tetrachlorophthalic anhydride with a sulfur tetrafluoride/hydrogen fluoride mixture provides an efficient synthesis... 

This technique is useful for monomers which are difficult to polymerize by other techniques. Thus, chlorotrifluoroethylene can be polymerized anodically with good efficiency by electrolysis in liquid hydrogen fluoride - potassium fluoride or trifluoroacetic acid - trifluoroacetic anhydride - potassium trifluoroacetate 631 ... 

For example, thermolysis of (177) in the presence of DMAD resulted in formation of the dimethyl isothiazoledicarboxylate (182) (>90% yield). Benzonitrile sulfides, generated by the rare 1,3-elimination of two equivalents of hydrogen fluoride from (179), reacted with maleic anhydride (MA) to give dihydrofuro[3,4-d]isothiazole-4,6-diones (183 X = O). 

Crystals of magnetic oxide have been obtained in a variety of ways, such as by calcination of sodium carbonate and ferrous chloride 1 by fusion of potassium sulphate and iron phosphate 2 by the action of hydrogen chloride upon heated ferrous oxide 3 and by ignition of ferrous fluoride with boric anhydride.4... 

A number of carboxylic anhydrides have been converted into trifluoromethyl compounds by treatment with sulfur tetrafluoride, usually in the presence of hydrogen fluoride. As in the case of carboxylic esters, vigorous conditions are needed. Some examples have been presented in Houbcn-Weyl, Vol. 5/3, pp 92, 93. Depending on the reaction conditions, different compounds can be isolated. In some, cyclic di- or tetrafluorinated ethers predominate. 1.253.254 Upon reaction with sulfur tetrafluoride/hydrogen fluoride, pyromellitic dianhydride, as well as pyromellitic acid (benzcnc-l,2,4,5-tetracarboxylic acid), gives a mixture of 1,2,4,5-tet-rakis(trifluoromethyl)bcnzcne, 1,1,3,3-tetrafluoro-5,6-bis( trifluoromethyl)- ,3-dihydroisoben-zofuran, and the fully fluorinated tetrahydrobenzodifuran in an 85-88 10-13.5 1-2 ratio (see formation of compounds 13-15, vide supra)d ... 

A group of reactions involving 16,17-epoxy-pregnane derivatives illustrates the facility of C(is) methyl migration to an electron deficient C(i ). The i6a,i7a-epoxypregnan-20-ones (13) react with acetic anhydride and toluene- -sulphonic acid [24], hydrogen fluoride [23], and other acidic reagents [23,26], to form i7a-acetyl-i7/5f-methyl-i8-nor-olefins (14) and (15). The preferred position of the double bond apparently... 

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