Radical formation using hypervalent

The use of the hypervalent iodine reagent [bis(trifluoroacetoxy)iodo]benzene has been reported to be effective in the synthesis of C-nucleoside-like compounds. Radical decarboxylation of a suitably protected uronic acid, initiated photochem-ically, followed by addition of a heterocyclic base provided the C-nucleoside in high yield.154 The mode of action involves initial radical formation of 122 (Scheme 33), followed by introduction of the base and radical coupling.155 The anomeric selectivity was high in some examples, and low in others—lepidine gave the highest proportion of the ( anomer. Isolated yields were poor to moderate. 

V. V. Zhdankin, in his chapter, summarizes the use of hypervalent iodine reagents for carbon-carbon bond formations. The generation of radicals with hypervalent iodine compounds is used in decarboxylative alkylations of organic substrates, whereas phenols and phenol ethers seem to be ideal substrates for... 

In addition, the reaction between hypervalent iodine reagents such as iodosyl-benzene or its diacetate derivative with molecular iodine has been employed frequently in aliphatic amination reactions. These processes start from an initial formation of an alkyl hypoiodite derivative, which can promote subsequent radical amination pathways. An excellent use of this concept is the Suarez methodology for the generation of diversified aminated carbohydrate structures [80-86]. Although the hypervalent iodine reagent is not directly involved in the amination reaction, the efficiency of the method deserves mentioning within the present chapter. It was recently extended to catalytic transformations [87],... 

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