Electrolysis of ethyl propiolate (1) and an excew of methyl iodide at a platinum cathode in hexamethylphosphoric triamide (HMPA) or Nfl-dimethylformamide (DMF) solution containing tetra-n-butylammonium salt gave the acetylenic esters 2, 3, and 4. Similar electrochemical reactions of a,@-acetylenic esters 2, 5, and 9 with methyl iodide took place in good yields to give the corresponding a, a-dimethyl@, y-acetylenic esters 3 and 4, 4, and 10, ...
