Halogenation-oxidation-reduction route

Research has focused on improving the efficiency of the halogenation-oxidation-reduction route by using reagents that perform the halogenation-oxidation in one step. Hypochlorous acid-hypochlorite and hypobromous acid-hypobromite " systems have also been explored for the direct conversion of oximes to a-bromonitroalkanes and a-chloronitroalkanes respectively. Some A-haloheterocycles have been reported to affect direct oxime to a-halonitroalkane conversion, and on some occasions, the use of NBS or the free halogens also leads to a-halonitroalkanes. A mixture of oxone and sodium chloride as a suspension in chloroform is reported as a one-pot method for the direct conversion of oximes to a-chloronitroalkanes. ... 

The last two of these reactions also feature a reduction in oxidation state. A closely related route is halogen exchange usually in the presence of an excess of the halogenating reagent , e.g. ... 

Section III,G,2. Sequential oxidative addition, halogenation at Si, and reductive elimination provide an elegant route to pure R2SiHX derivatives (cf. Section III,C,1 and Table XII, entry 14) (453) ... 

Oxidative-addition reactions (see Section 10) play a widespread role in catalytic processes and constitute one of the principal routes for the activation and dissociation of saturated bonds, including H—H, C—(X = halogen), strained C—C bonds, and in certain cases, C—H bonds. Correspondingly, the reverse process, i.e., reductive elimination, constitutes a widespread route for the formation of such bonds. The latter process frequently is the product-forming step in catalytic reactions such as hydrogenation, car-bonylation and hydroformylation ". ... 

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