Oxygen glycol cleavage

While anodic oxidation of simple alcohols is of limited utility, direct oxidation of vicinal diols and related compounds is an excellent method for achieving oxidative cleavage to the corresponding carbonyl or carbonyl-acetal products, as in Eqs. (53) and (54). Unlike certain chemical glycol cleavage reactions, the anodic method is not limited by the stereochemistry of the substrate oxygens [132]. 

The key-step in the synthesis of 5-(7-methyl-D-mannose from L-quebrachitol was the glycol cleavage of the isopropyUdene derivative 15 (Scheme 6). L-Tagatose was prepared by a similar, but extended reaction sequence incorporating a Mitsunobu inversion at the future C-4. L-Olucose has been synthesized in many steps from cycloheptatriene (Scheme 7) via the meso-intermediate 16 which was desymmetrizized by enzymic monoacetylation. Transformation to the allylic alcohol 17 involved inter alia stereoselective oxygenation and cis-hydroxylation. Ozonolysis, followed by... 

Xing G, Barr EW, Diao YH, Hoffart LM, Prabhu KS, Amer RJ, Reddy CC, Krebs C, Bollinger Jr JM. 2006. Oxygen activation by a mixed-valent, diiron(II/III) cluster in the glycol cleavage reaction catalyzed by myo-inositol oxygenase. Biochemistry 45 5402-5412. 

In contrast to phosphorus esters, sulfur esters are usually cleaved at the carbon-oxygen bond with carbon-fluorine bond formation Cleavage of esteri nf methanesulfonic acid, p-toluenesidfonic acid, and especially trifluoromethane-sulfonic acid (tnflic acid) by fluoride ion is the most widely used method for the conversion of hydroxy compounds to fluoro derivatives Potassium fluoride, triethylamine trihydrofluoride, and tetrabutylammonium fluoride are common sources of the fluoride ion For the cleavage of a variety of alkyl mesylates and tosylates with potassium fluoride, polyethylene glycol 400 is a solvent of choice, the yields are limited by solvolysis of the leaving group by the solvent, but this phenomenon is controlled by bulky substituents, either in the sulfonic acid part or in the alcohol part of the ester [42] (equation 29)... 

The initiation step of this anodic oxidation of glycols may be the electron transfer from the lone pah-electrons of the oxygen atom to the anode. This anodic cleavage of 1,2-glycols has beat utilized for a variety of organic syntheses. ... 

Oxidative cleavage of l -deols. The reagent catalyzes the cleavage of 1,2-glycols by oxygen in an aprotic, polar solvent (benzonitrile, DMF, sulfolane). Yields of aldehydes tre 60-81 %. Further oxidation to carboxylic acids is possible.1... 

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