Oxidation cleavage of diol

In general, tertiary alcohols are unaffected by chromic acid, but tertiary 1,2-diols are cleaved readily to give ketones, provided they are capable of forming cyclic chromate esters. For oxidative cleavage of diols, see Section 5.4. 

C2 symmetry is compatible with chirality. For the oxidative cleavage of diols to aldehydes, see p. 443. 

In summary. Oxidative cleavage of diols by Ru(PPh3)3Cl2/H202 is a further but not final step in the development of a catalytic alternative to ozonolysis. As in the case of epoxidation, the use of alkyl hydroperoxides instead of hydrogen peroxide may bring additional benefits however, this field has scarcely been explored (77). 

Oxidative cleavage is a process that cleaves covalently bound carbon atoms to give two functionalized carbon atoms. Reactions of this type include oxidative cleavage of a C=C unit, as in the ozonolysis reaction of Chapter 10 (Section 10.7.2) to give carbonyl derivatives. The C-C bond of 1,2-diols may also be oxidatively cleaved to give carbonyl derivatives. This section will revisit ozonolysis and then introduce the oxidative cleavage of diols. 

Lead tetraacetate (abbreviated LTA) reacts with diols to give the same kind of oxidative cleavage. When 69 is treated with LTA, the initial cyclic product is cyclic intermediate 73, which fragments to butanal and acetaldehyde. Periodic acid gives the same cleavage reaction. Both periodic acid and lead tetraacetate are mild and effective reagents for the oxidative cleavage of diols. 

Figure 10.45 Alternative bishydroxylation methods for the use in the oxidative cleavage of diols in the reconstitution strategy...

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