Methyl esters (RCO2CH3) undergo a cleavage reaction to yieldcarboxylate ions plus iodomethane on heating with LiI indimethylformamide, shown below.
The following evidence has been obtained: (1) The reaction occursmuch faster in DMF than in ethanol. (2) The corresponding ethylester (RCO2CH2CH3) cleaves approximately 10 times more slowly than the methyl ester.
(a) Propose a mechanism for the reaction.
(b) What other kinds of experimental evidence could you gather to support your hypothesis?