Carbohydrates reactions with hypochlorite

Carbohydrates have a wide range of structural variations and these can be used to evaluate steric and stereoelectronic effects. This feature has been utilized in hetero-Diels-Alder cycloadditions. Thus, 2,3 5,6-di-0-isopropylidene-D-mannonolactone oxime, on reaction with tert-butyl hypochlorite, gives the corresponding 1-chloro-l-nitroso derivative 1 which is stable at 20°C for several days the configuration was assigned by X-ray analysis92-93. 

Primary alcohol groups can also be mildly and selectively oxidized to carboxyl groups by reaction with 2,2,6,6-tetramethyl-l-piperidine oxoanunonium ion (TEMPO) in the presence of hypochlorite and bromide [129,130]. The specificity for the oxidation of primary alcohols in the presence of secondary alcohols in carbohydrates occurs because of the bulky nature of the TEMPO reagent, similar to the specificity obtained with the bulky trityl chloride. The mechanism for the oxidation of primary alcohols with TEMPO is given in reaction 4.140. 

It has been assumed that the reactions of chlorine and hypochlorite with carbohydrates proceed mainly by the radical mechanism because they are retarded in the presence of radical scavengers, such as chlorine dioxide ... 

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