Hypohalite reactions

The acyl hypohalit reaction with iodine ob a halogen component is the well-known Prevost reaction,18i0 whioh has found some application during recent years in the field of natural prodwtB.. u. . w. In thiB ease the acyl hypoholite is acetyl hypoiodite, generated by reaction of iodine with silver nitrate in glacial acetic arid (Eq. 130). 

II. Functionalization of the Angular Methyl Groups / 237 General principles of substitution / 237 Lead tetraacetate oxidations / 240 Hypohalite reactions / 246 Photolysis of nitrites (Barton reaction) / 253 A-Chloroamine reactions (Hoffmann-Lofller reaction) / 257 Ketone irradiations / 260 Summary / 264... 

Diraethyldihydroresorcinol (dimedone) is converted into 3,3-di-methylglutaric acid on treatment with sodium hypochlorite or sodium hy-pobromite. As a p-diketone, it suffers alkaline hydrolysis to 3,3-dimethyl-5-ketohexanoic acid, which undergoes regular hypohalite degradation of the methyl ketone end (equation 429) [735. Both the hydrolytic opening of the ring and the hypohalite reaction are accomplished in one step [699],... 

Electrophilic fluorination by substitution of hydrogen at unactivated tertiary carbon has been achieved by use of either CF3OF or elementary fluorine (diluted with N2). Electron-attracting substituents direct the reaction to remote C—H bonds, suggesting that the reaction has electrophilic rather than free-radical character. Examples include the 9a-fluorination of 5a-androstane-3/8,17/8-diol esters (309), 14a-fluorination of various 5a,6j8-dichloro-3,17-disubstituted steroids of type (310), and 17a-fluorination of 5a-cholestan-3j8-yl esters or their 5a,6/8-dichloro-derivatives. Hypobromite and other hypohalite reactions for the functionalization of unactivated carbon atoms are reviewed. ... 

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