Fluoroboric acid-acetic anhydride

Fluoroboric acid, sodium salt, preparation of, 54, 30 Fluoroboric acid-acetic anhydride, 54, 99... 

Tetrathiafulvalenes.—Preparations of ever more elaborate compounds of this class have been announced. Coupling of the dithiolethiones (293 n = 2 or 3) by means of triethyl phosphite affords the tetracyclic derivatives (294) °° mixtures of the dithioleselones (295) and (296) give good yields of the crossed product (297) in this reaction.The tetraselenafulvalene (299) is obtained by photolysis of 3,4-diphenyl-l,3-diselenole-2-thione (298). Even cyclophanes containing the tetrathiafulvalene structure have been reported thus compound (300), on sequential treatment with methyl iodide, sodium borohydride, and fluoroboric acid-acetic anhydride, affords a mixture of the tetrathiafulvalenophanes (301) and (302), ° and the paracyclophanes (304) and (305) result from the para-substituted benzene (303). 

Acetic acid Acetic anhydride Acid mixtures Battery fluids Chloroacetic acid Chlorosulphonic acid Chromic acid Dichloroacetic acid Fluoroboric acid Fluorosilicic acid... 

Burgstahler et al. diazotized the sparingly soluble hydrochloride of 3,4-di-r-butylaniline at O-S", treated the filtered solution with sodium fluoroborate, and obtained the diazonium fluond>orate. This salt underwent slow solvolysis in a mixture of acetic acid — acetic anhydride with formation of the corresponding acetate. 

The water of hydration of these complexes can be replaced with other coordinating solvents. For example, the ethanol and methanol solvates were made by dissolving the hydrates in triethyl and trimethyl orthoformate, respectively (81,82). The acetic acid solvates are made by treating the hydrates with acetic anhydride (83). Conductivity and visible spectra, where appHcable, of the Co, Ni, Zn, and Cu fluoroborates in A/A/-dimethylacetamide (L) showed that all metal ions were present as the MLg cations (84). Solvated fluoroborate complexes of, Fe +, Co +, , Cu +, and in diethyl... 

Caution The reaction of ftuoroboric acid vrith acetic anhydride is exothermic and should be conducted with caution. Under an atmosphere of nitrogen, 102 g. (1.0 mole) of acetic anhydride (J. T. Baker Chemical Company) is cooled to —40° in a dry ice—acetone bath. Then, with magnetic stirring, 20.4 g. (0.12 mole) of 50% fluoroboric acid (J. T. Baker Chemical Company) is added over 10 minutes. After carefully warming to 0°, the freshly prepared solution is used immediately. 

Quaternary oxazolium and benzoxazolium salts are prepared by alkylation (see Section 4.18.3.1.2.2) they are also produced by the action of acetic anhydride and an inorganic acid (perchloric or fluoroboric) on the appropriate acylamino ketone (equation 98). iV-Aryl derivatives are obtained in this way. 

Stirring with a freshly prepared 10% solution of fluoroboric acid in acetic anhydride (prepared under nitrogen at —40°). After the resulting suspension has been stirred for 20 min. the white precipitate is collected on a sintered glass funnel (medium porosity) under vacuum and washed thoroughly with three 75-ml. portions of ether. The product is then dissolved in a minimal amount of boiling acetone (ro., 300 ml.) and cooled in a... 

Whereas pyrazoles are quite readily iV-nitrated by nitric acid in acetic anhydride or with nitronium fluoroborate, imidazoles are usually far too basic, and give the nitrate salts instead. A nitro substituent, however, decreases the basicity sufficiently to allow iV-nitration to occur. The A -nitro compounds are subject to thermal rearrangement to the 2- and 4-nitro isomers, pointing to an alternative route to such compounds [63]. 

They react with trityl tetrafluoroborate in acetonitrile or tetra-fluoroboric acid in acetic anhydride giving the 2-unsubstituted... 

Alkoxy- or 2-alkylthio-l,3-dithioles (119) are easily prepared. 264,26 5 They react with trityl tetrafluoroborate in acetonitrile or tetra-fluoroboric acid in acetic anhydride giving the 2-unsubstituted... 

A soln. of di- er -butylcyclopropenone in pentane added during 0.5 hr. at 0° under Ng to a soln. of er butyllithium in the same solvent, stirred 0.5 hr. without cooling, the ethereal soln. of the resulting intermediate rapidly stirred and treated at 0° with a 10%-soln. of fluoroboric acid in acetic anhydride, and stirring continued 20 min. tri- cr -butylcyclopropenyl fluoroborate. Y 68-79%. J. Cia-battoni et al., Org. Synth. 54, 97 (1974). 

Carboxylic acids can be prepared in moderate-to-high yields by treatment of diazonium fluoroborates with carbon monoxide and palladium acetate or copper(II) chloride. The mixed anhydride ArCOOCOMe is an intermediate that can be isolated. Other mixed anhydrides can be prepared by the use of other salts instead of sodium acetate." An arylpalladium compound is probably an intermediate." ... 

LEAD FLUOROBORATE (13814-96-5) Pb (BF4)2 Decomposes in water or acids, forming ionic lead and fluoboric acid solution. Aqueous solution incompatible with sulfuric acid, alkalis, ammonia, aliphatic amines, alkanolamines, alkylene oxides, amides, epichlorohydrin, organic anhydrides, isocyanates, nitromethane, vinyl acetate. Corrodes aluminum and most other metals. Thermal decomposition releases lead fumes and hydrogen fluoride gas. On small fires. 

Nitro compounds, ar. Nitrobenzene, m-Dinitrobenzene o-Nitrophenol N-Nitramines Oxonium fluoroborate Trialkyloxonium salt T rialkyloxonium fluoroborate Pyrylium fluoroborate Carboxylic acid esters HCOOC H, p-Nitro-phenyl formate Isopropenyl acetate Salicylic acid esters Ethyl cyanoacetate Chloroformic acid esters Ethyl chloroformate, ClCOOCJi A Methyl trichloroacetate Diethyl oxalate Ethyl malonate Orthoformic acid esters. Ethyl orthoformate (RCOj O (CH,C0)20, (Cfi COj O, (CF,C0)20 n-Octanoic anhydride (C,H,C0)20 R-OOH, Cflg-OOH Cumene hydroperoxide Peroxides... 

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