Oxidation hypofluorous acid — acetonitrile

The hypofluorous acid/acetonitrile complex has also been used for the oxidation of secondary alcohols and for the Baeyer Villiger oxidation of ketones.24-25... 

The reactivity of a terminal 1,13-diene with an interstitial deca(difluoromethylene) chain 1 is lower towards expoxidation with hypofluorous acid/acetonitrile complex21 due to the electron-withdrawing effect of the perfluoroalkyl chain attached directly to the C = C bond. The diepoxide 2 is obtained by repeated reaction with a very large excess of the oxidizing agent.21... 

It is possible that the iodine and base could be generated in the way cited earlier for the oxidation of 2-methylnaphtho-quinone. Fluorine forms a hypofluorous acid-acetonitrile complex when it is passed into wet acetonitrile. This complex has been used to convert olefins, such as undecylenic acid, oleic, and cinnamic acid to the corresponding epoxides in 90% yields.294 The disadvantages of the process are the need to handle the very reactive fluorine and the need to recycle the by-product hydrogen fluoride. 

Though it requires vigorous conditions and is less common than nucleophilic epoxidation, electrophilic epoxidation of aperfluoroalkene is possible with the potent combination of chromic oxide and fluorosulfonic acid, providing another route to hexafluoropropylene oxide (1). As a further example of electrophilic attack, hexa-fluoro Dewar benzene (3) is transformed into either a mono- or a diepoxide by the powerful hypofluorous acid-acetonitrile complex.The fact that the much weaker electrophile MCPBA readily epoxides such electron-deficient alkenes as ethyl pentafiuoromethacrylate (4) suggests that it actually reacts via nucleophilic attack at the [3-carbon. 

Disulfides are generally oxidized with cleavage of the S —S bond. Hypofluorous acid in acetonitrile solution oxidizes sulfur atoms in bis(trifluoromethyl) disulfide to the highest oxidation state and, in addition, inserts an oxygen bridge between the sulfur atoms (Table 19).304 A sulfonyl chloride 18 is similarly obtained by the reaction of a substituted diphenyl disulfide with hypochlorous acid generated from chlorine and aqueous acetic acid.305... 

Trifluoromethaneseleninyl chloride (3) can be prepared by the reaction of trifluoromethane-sclcnenyl chloride with ozone whereas nitrogen dioxide transforms the initially formed acid choride to the anhydride (CF3Se0)20.316 Trifluoromethaneselenenic acid chloride and bromide are oxidized with hypofluorous acid in acetonitrile to the corresponding seleninyl halides 3 and 4, respectively.204 When an excess of hypofluorous acid is employed, the selenenyl halides and trifluoromethaneseleninic acid (5) are oxidized to the anhydride 6.304... 

An easily prepared acetonitrile complex of hypofluorous acid (HOF-CH3CN) serves an excellent reagent for the oxidation of alkenes with pendant alcohol or carboxylic acid functionalities <1996TL531>. 

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