Glycol-cleavage oxidation procedure

Some of the earliest work in the oxidation of alkenes was performed by oxidation with potassium permanganate. Under acidic and neutral conditions the intermediately formed glycols are oxidized, generally leading to cleavage of the carbon-carbon bond. Thus, such procedures have seldom been synthetically applied to diene oxidation. One notable... 

Oxidative cleavage of vfc-glycols to carbonyl compounds with NBS in the presence of a catalytic amount of triphenylbismuthine typical procedure... 

A procedure has been described for the determination of irregular head-to-head and tail-to-tail linkages in polyepichlorohydrin. This procedure involves dechlorination of the polymer with lithium aluminum hydride, cleavage of the resultant poly-(propylene oxide) with n-butyllithium, and analysis by gas chromatography to determine the relative amounts of the respective dipropylene glycols. 

The combination of A -bromoacetamidc, silver acetate, and dry acetic acid has been shown to be superior to Woodward s procedure for the rfy-hydroxylation of olefins. Work up of the reaction mixture is simply effected by hydrolysis of the dioxolenium ion, followed by cleavage of the hydroxyacetate intermediate with lithium aluminium hydride. The use of a co-oxidant, such as sodium chlorate or hydrogen peroxide, allows the addition of catalytic quantities of osmium tetroxide to prepare c/y-diols from olefins. However the reaction is often complicated by further oxidation of the glycol to the a-ketol. The use of tertiary amine A -oxides, particularly A -methylmorpholine A -oxide, prevents this oxidation and gives higher yields of the desired product (Table 6). Another variation on this theme employs... 

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