Oxidation using hypochlorite and chlorite anions

Selected examples of the oxidation of primary and secondary alcohols 

Alcohol Reaction conditions % recovered alcohol % yield carbonyl compound 

Oxidation of primary alcohols by hypochlorite moderated by TEMPO 

Method A Aqueous NaOCl (10%, 50 ml, 0.079 mol) is added to the alcohol (0.01 mol) and TBA-HSO4 or TBA-Br (0.5 mmol) in CH2CI2 or EtOAc (25 ml) at room temperature and the reaction is monitored by GLC. On completion, the aqueous phase is separated and extracted with CH2C12 or EtOAc (2 x 75 ml). The combined organic solutions are dried (MgS04) and evaporated to yield the aldehyde or ketone. 

Method B with added TEMPO The alcohol (3 mmol) in CH2C12 (8 ml) is mixed with KBr (30 mg), TBA-C1 (39 mg, 14 mmol) and TEMPO (4.5 g, 28 mmol) in aqueous NaHC03 (sat. soln, 5 ml). The mixture is cooled to 0°C and a mixture of aqueous NaOCl (1.95M, 

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Hypochlorites, chlorites, chlorates and perchlorates all represent the same dangers, which are linked to the fact that they are strong oxidants. The danger is not directly linked to the importance of the oxidation state of chlorine atom and this is partly for kinetic reasons. The main factors of the accidents described in the technical literature are not the intrinsic properties of each anion, but rather the frequency with which they are used. So chlorates and perchlorates are more often involved in accidents than hypochlorites and especially chlorites, which are hardly used. Thus the classification below does not provide positive indications about the dangerous properties of each substance mention. ... 

Immobilized TEMPO has been used for the one-pot oxidation of alcohols to carboxylic acids as well.26 For this purpose TEMPO resin 1 was combined with two ion-exchange resins loaded with chlorite anions and hydrogen phosphate in the presence of catalytic amounts of potassium bromide and sodium hypochlorite in solution. The reaction required work-up for the removal of salts, but tolerated several protecting schemes and afforded pure products in good to excellent yields. The reaction is initiated by catalytic TEMPO oxidation of alcohols to aldehydes driven by dissolved hypochlorite followed by oxidation to the carboxylic acids effected by chlorite. 

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