Metaperiodic acid, oxidant

The method is based on the fact that periodic acid or the reagent more commonly used, sodium metaperiodate, will oxidize a-glycols and cleave the carbon-carbon bond, with the formation of dialdehydes.166166 A pentofuranosylpyrimidine (XVIII, R = a pyrimidyl group) would be expected to consume one mole of metaperiodate per mole of nucleoside. The dialdehyde (XIX) resulting from this oxidation would... 

In the oxidation of mandelic acid by metaperiodic acid, ° a complex is formed which is considered to be the reactive intermediate. 

Desilylation of the major jjw-isomer, followed by oxidative cleavage with sodium metaperiodate, liberates the 3-hydroxy-2-methyl carboxylic acids. The immolative character of this method, i.e., the destruction of the chiral auxiliary reagent in the final glycol cleavage, is a drawback. 

The method of choice for preparing thietane oxides is the oxidation of thietanes. This can be conducted using hydrogen peroxide, sodium hypochloride -, sodium metaperiodate , NaI04 and m-chloroperbenzoic acid . 

The selenides prepared by any of these methods can be converted to selenoxides by such oxidants as hydrogen peroxide, sodium metaperiodate, peroxycarboxylic acids, 1-butyl hydroperoxide, or ozone. 

Another factor to be considered in the use of periodate ion as oxidizing agent is the desired pH. Potassium metaperiodate in solution gives29 a pH value of about 4. For values of pH below 3 to 4, pure periodic acid or acid-salt solutions must be used. For values of pH above 5, solutions containing potassium hydroxide and potassium metaperiodate must be employed.246... 

In a study of the oxidation of 2-amino-2-deoxy-D-glucose (D-glucosamine) derivatives, Neuberger12 obtained better results using sodium metaperiodate (at its accompanying pH of 3 to 4) than with periodic acid at lower pH values and a pH of 4.5 was found by Jeanloz and Forchielli78a to be optimal for these derivatives. 

Mild allylic oxidation of the A-2-crotyl-substituted thiadiazolidinone 1,1-dioxide 140 by sodium metaperiodate/ ruthenium trichloride hydrate (RuC13) gave the aldehyde 141. Excess oxidizing agent afforded the carboxylic acid 142 (Equation 26) <1999EJ02275>. 

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