Radical Carboxylation with Methyl Oxalyl Chloride

5 Radical Carboxylation with Methyl Oxalyl Chloride 

Kim and Jon recently reported a unique method for the synthesis of esters via a radical reaction of alkyl iodides with methyl oxalyl chloride under in-adiation con- 

4 Modem Free Radical Methods for the Synthesis of Carbonyl Compounds 

It should be noted that Kim and Jon also reported the synthesis of thioesters by the reaction of alkyl iodides with 5-phenyl chlorothioformate under similar irradiation conditions [79]. 

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Methyl oxalyl chloride was also employed as a radical trap for the same purpose (Scheme 18) [40c], Radical reaction of an alkyl iodide with methyl oxalyl chloride in the presence of hexabutylditin under photochemically initiated conditions affords an acid chloride along with a small amount of the corresponding methyl ester. Sequential radical reaction involving cyclization and carboxylation can be performed using methyl oxalyl chloride. 

ChlorocarbonyUition. The reaction of adamantane (1) with one equivalent of oxalyl chloride under free-radical conditions (benzoyl peroxide) followed by methanolysis gives a mixture of methyl adamantane-1- and -2-carboxylate, (2 and 3) easily separable by fractional distillation. Chlorocarbonylation with a fivefold excess of reagent followed by methanolysis gives a mixture of methyl adamantane-... 

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