Bi(III) carboxylates as efficient reagents for preparation of esters under mild conditions. A new method for the protection of carboxylic acids

Bi(III) carboxylates have been obtained by reaction of triphenylbismuth with various monocarboxylic acids. By a ligand-exchange reaction, these Bi(III) carboxylates react with tertiary or benzylic-type bromides and afford esters. This reaction sequence constitutes a new efficient way for the temporary protection of carboxylic acids under mild conditions.