Deuteration of α,β-acetylenic esters, amides, or carboxylic acids without using deuterium gas: synthesis of 2,2,3,3-tetradeuterioesters, amides, or acids

An easy, simple, rapid, and nonhazardous deuteration of the C-C triple bond of α,β-acetylenic esters, amides, or acids by means of samarium diiodide in the presence of D₂O, provides an efficient method for synthesizing 2,2,3,3-tetradeuterioesters, amides, or carboxylic acids, respectively. When H₂O is used instead of D₂O, saturated carboxylic esters, amides, or acids were isolated. A mechanism to explain these reduction reactions has been proposed.