Carboxymethylation/lactonization, acetic

Acetic acid can be used in carboxymethylation/lactonization reactions of arylalkenes 184 catalyzed by electrochemically generated Mn(OAc)3 and Cu(OAc)2... 

The stoichiometric oxidation of alkenes by Mn(OAc)3 in acetic acid at 120 °C affords 7-lactones n good yield, via the homolytic addition of carboxymethyl radical to the double bond (equations 104 and 205).504-506... 

Exposure of longifolene to manganic acetate in refluxing acetic acid-acetic anhydride furnished in poor yield (9%) the product (66), the stereochemistry of which remains unresolved. Under the same conditions, camphene gave in 30% yield y-lactone mixture (67), in which one isomer predominated 49). A carboxymethyl radical arising from the thermolysis of Mn (III) acetate is considered to be the reactive species in such reactions (50). 

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