Perchloryl fluoride

Perchloryl fluoride, C103 F, has been prepared by the action of elemental fluorine on potassium perchlorate,1 by the electrolysis of sodium perchlorate in anhydrous hydrogen fluoride,2 and by reactions of various metal perchlorates with fluorosulfuric acid3 or antimony(V) fluoride.4 Although the latest methods (with HS03 F or SbFs or both) are more convenient than the first ones, they suffer the disadvantages that elevated temperatures are 

5 Virginia Polytechnic Institute and State University, Blacksburg, Va. 24061. 

The new compound perbromyl fluoride, Br03 F, was recently successfully synthesized in high yield by an adaptation of this procedure with potassium perbromate used in place of the perchlorate.6 

The apparatus consists of a simple vacuum manifold similar to that shown in Fig. 4. The vacuum manifold should be fabricated from nickel or Monel metal, with silver-soldered or Swagelok connections. Valves should be of Monel metal, and the traps and scrubber, the function of which is to remove hydrogen fluoride vapor from the C103 F product, may be constructed conveniently of poly(chlorotrifluoroethylene) (Kel-F) tubing. A nickel cylinder of 500-ml. or 1-1. capacity serves as a reaction vessel, and a 500-ml. Monel bulb or similar vessel may be used as a product receiver. The scrubber (about 1-in. o.d.) is charged with pellets of sodium fluoride prepared in a separate operation by heating sodium 

The product yield may be established by pressure measurements on the receiver of known volume or by weighing. The purity of the product may be confirmed by infrared spectrophotometry7 or mass spectrometry. The only significant impurity found was hydrogen fluoride in trace amounts. This may be determined acidimetrically by passing a measured quantity of the product through water. 

Tetrachloroethylene, 278pp. US Department of Health and Human Services, Public Health Service, 1997 

The 2003 ACGIH threshold limit value-time-weighted average (TLV-TWA) for perchloromethyl mercaptan is 0.1 ppm (0.76 mg/m ). 

Production of fungicides vulcanizing accelerator in rubber industry 

Toxicology. Perchloromethyl mercaptan is a severe pulmonary irritant and lacrimating agent fatal exposure has also caused liver and kidney injury. 

Humans can withstand exposures to 70mg/m (8.8 ppm) eye irritation begins at lOmg/m (1.3 ppm). Acute exposure to higher concentrations may cause coughing, dyspnea, lacrimation, nausea, cyanosis, convulsions, and death due to lung edema.  

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An alternative route to 6a- uorosteroids was developed by treating the enol acetate (93) of a A -3-one with perchloryl fluoride ia aqueous dioxane to obtain a mixture of the 6-fluoro-epimers (94) which were converted iato the 6a-fluoro-A -3-ones (95) on treatment with. ... 

Perchlorylation. The stabiUty of perchloryl fluoride [7616-94-6] FCIO, makes possible perchlorylation of aromatics, a reaction closely related to the Friedel-Crafts acylation (159) ... 

The perchloryl fluoride [7616-94-6] FCIO, the acyl fluoride of perchloric acid, is a stable compound. Normally a gas having a melting poiat of —147.7° C and a boiling poiat of —46.7°C, it can be prepared by electrolysis of a saturated solution of sodium perchlorate ia anhydrous hydrofluoric acid. Some of its uses are as an effective fluorinating agent, as an oxidant ia rocket fuels, and as a gaseous dielectric for transformers (69). 

Synthetic procedures are available for the preparation of fluoro, chloro, bromo and iodo compounds from the corresponding lithio derivatives. Perchloryl fluoride (FCIO3), N-chlorosuccinimide, bromine and iodine are examples of reagents which can be used to introduce fluorine, chlorine, bromine and iodine, respectively. 

Cobalt Perchloryl fluoride Chloroacetophenone Potassium cyanide... 

Perchloromethyl mercaptan Perchloryl fluoride Petroleum distillates (naphtha)... 

Enol ethers are readily attacked in buffered medium by electrophilic reagents such as halogens, A -haloamides, perchloryl fluoride and organic peracids to give a-substituted ketones. Similarly, electrophilic attack on... 

The enamines, enol ethers and enol acetates of A -3-keto steroids provide important substrates for fluorination with FCIO3. Reaction of such A -enol ethers and acetates (6) with perchloryl fluoride results in 6a- and 6jff-fluoro-A -3-ketones (7) and (8), the latter representing the more abundant isomer. Tetrahydrofuran or dioxane-water mixtures appear to be particu-... 

In contrast to the above behaviour, the corresponding A -pyrrolidyl enamines (9) react with perchloryl fluoride in ether to furnish the 4,4-difluoro-A -3-ketones (10) contaminated with some of the 4-fluoro-A -3-ketones (11). Similar results are obtained with the corresponding 19-norsteroids... 

The reaction with the jff,y-unsaturated A °k3 ketone (20) in pyridine proceeds in 25% yield to the 10j -fluoro ketone (21). a,yS-Unsaturated ketones do not react with perchloryl fluoride. 

A novel reaction of perchloryl fluoride with aromatic substrates was discovered by Neeman and Osawa, the oxofluorination reaction. These authors found that reaction of indene with perchloryl fluoride in dioxane-water yields five products, the major product being, 2-fluoroindanone. When applied to 6-dehydroestradiol diacetate (24) there is obtained as the major product the 7a-fluoro-6-ketone (25). Borohydride reduction of the... 

C—O bonding and Cl—F fission of the intermediate cw-fluoro chlorate (29a), which in turn undergoes oxidation to the fluoro ketone (25) by a concerted elimination of chlorous acid. A similar transition state (30) approximating an allylic carbonium ion could be involved in the reaction of the dienol derivatives (6) with perchloryl fluoride, which would be expected to give rise to the c/5-adduct (30a). Reaction of the latter with water leads to product and chlorate ion. 

It is more reactive than perchloryl fluoride and therefore not without danger. It forms, for instance, a highly explosive product with pyridine. Like perchloryl fluoride it reacts with enol ethers, esters and enamines, but at lower temperature (—78°) to yield the fluorinated ketones as well as addition... 

Perchloryl fluoride, well known for its ability to fluonnate organic substrates, has become a reagent with limited appeal. Its loss of popularity stems from difficult... 

Aromatic substrates react well with perchloryl fluoride after conversion into organohthium intermediates [104, 105] (equations 58 and 59). 

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