Diols, vicinal with sodium periodate

The preparation of an aldehyde-SAM was achieved by treating the vicinal diol-SAM with sodium periodate. The preparation of an activated tripodal structure on a hydroxyl terminated SAM has been published by Ichimura and coworkers.64 These authors reported the reaction of SAMs formed by mercapto-alkanols such as 2-mercaptoethanol, 6-mercaptohexanol, and 16-mercaptohexadecanol with SiCl4, with the formation of a tripodal derivative bearing a terminal Si—Cl bond amenable to react with methanol or water. 

This last compound was selectively oxidised at the vicinal diol function with sodium periodate and successively with Jones s reagent, affording the desired acid 8. Direct esterification of compound 8 with dioxy-phenyl-ethanol 14, having phenolic functions protected with benzyl moieties, gave the key intermediate secoiridoid 9. The last step of the synthesis is the stereoselective reduction of 9 that afforded the alcohol 10... 

Moreover, 2,3-dialdehyde xylan may be obtained in the well-known glycol cleavage oxidation of vicinal diol units with sodium periodate, which can be further oxidized to give 2,3-dicarboxyl xylan. Figure 3 summarizes the structures of the possible oxidized repeating units. 

Periodate oxidation. Aldehyde groups can be easily introduced in most polysaccharides by reaction with sodium periodate. Vicinal diol structures give rise to dialdehydes. For dextran (I) having three adjacent hydroxyl groups in each non-branched anhydro glucopyranoside repeat unit the oxidation is a two step reaction ... 

Canadensolide (6.18) is an antifungal metabolite of Penicillium canadense that was reported in 1968. Its dilactone structure was established by a combination of spectroscopic and chemical methods. Thus the presence of the exocyclic methylene was suggested by the IR data and established by ozonolysis to give formaldehyde whilst the presence of the vicinal diol as part of the dilactone was indicated by the coupling pattern in the NMR spectrum and confirmed by hydrolysis and cleavage of the resultant diol with sodium periodate to give valeraldehyde (pentan-l-al). There is a similarity between these metabolites and avenaciolide (6.19), a metabolite of Aspergillus avenaceus. 

Alternatively, the carbonyl group may be reduced, the silyl group hydrolyzed, and the resulting vicinal diol cleaved with buffered sodium periodate to obtain the S-hydroxy aldehyde (e.g., eq 3). ... 

Osmium tetroxide reacts with double bonds to form cyclic osmate(VI) diesters (10), which can then be hydrolyzed to provide vicinal diols in good yields. - iK however, sodium periodate is also present, the diol is cleaved, as in Scheme 2, and carbonyl compounds are the final products. Periodate serves the additional purpose of regenerating osmium tetroxide, thus permitting the use of this expensive and toxic reagent in minimum amounts. 

Periodate Oxidation mainly of polysaccharide supports has become a popular activation technique for protein immobilization [149]. Sodium periodate (Nal04) can react with vicinal cw-hydroxyl groups on cellulose, dextran, or any other diols to produce aldehyde groups. These aldehyde groups can easily be transformed into secondary amines by reductive oxidation or to hydrazides by reaction with dihydrazine. Further attachment of ligands or spacer molecules can be performed via primary amino groups. 

Sodium periodate (sodium metaperiodate), NaI04 (mp 300 °C dec), which is commercially available, is applied mainly in aqueous or aqueous-alcoholic solutions. Like the free periodic acid, sodium periodate cleaves vicinal diols to carbonyl compounds [762], This reaction is especially useful in connection with potassium permanganate [763, 764] or osmium tetroxide [765], Such mixed oxidants oxidize alkenes to carbonyl compounds or carboxylic acids, evidently by way of vicinal diols as intermediates. Sulfides are transformed by sodium periodate into sulfoxides [322, 323, 766, 767, 768, 769, 770, 771, 772], and selenides are converted into selenoxides [773]. Sodium periodate is also a reoxidant of lower valency ruthenium in oxidations with ruthenium tetroxide [567, 774],... 

The results of some oxidations with potassium permanganate differ depending on the pH of the reaction. For example, stearolic acid gives 9,10-diketostearic acid at pH 7-7.5 (achieved with carbon dioxide) and azelaic acid on treatment at pH 12 [864]. In some reactions, potassium permanganate is used as a catalyst for oxidation with other oxidants, such as sodium periodate. Thus alkenes are cleaved to carbonyl compounds or acids via vicinal diols obtained by hydroxylation with potassium permanganate, followed by cleavage by sodium periodate [763, 552]. 

The resulting intermediate (—)-107 underwent cyclization to the piperidine (—)-108 after mesylation and base treatment. Acidic hydrolysis of the acetal and reduction of the resulting cycHc hemiacetal with sodium borohydride produced the triol (—)-109, the vicinal diol component of which was cleaved with periodate before reductive amination with hydrogen and palladium on carbon completed the synthesis of (+)-88. 

Two oxidants essentially dominate these oxidations lead tetraacetate in organic solvents and periodic acid in aqueous media. On occasion, other oxidation reagents cause the cleavage of vicinal diols ceric ammonium nitrate [424], sodium bismuthate [482, 483], chromium trioxide [482, 555], potassium dichromate with perchloric acid [949], manganese dioxide [817], and trivalent [779, 789] or pentavalent [798] iodine compounds. 

Electrochemistry427 can be used to regenerate an expensive or toxic reagent in situ. An example is the electrical regeneration of periodate that is used for the oxidation of vicinal diols such as sugars. When used with osmium oxidations, it can keep the level of the toxic metal reagent quite low. In Chap. 4, an example of the conversion of a naphthoquinone to its epoxide by electrolysis of aqueous sodium iodide was given. The sodium hydroxide and iodine produced by electrolysis react to form hypoiodite that adds to the double bond to form the hydroxyiodide, which then eliminates sodium iodide by the action of the sodium hydroxide to re-form the sodium iodide.428 Electricity can be used in oxidations and... 

Oxidative cleavage of vicinal diol functions in carbohydrates occurs with periodic acid (HIO4) or sodium metaperiodate (NaI04). The reaction proceeds through a cyclic intermediate and is similar to what we encountered with diols in Section 15.11. 

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