A Rapid and Efficient Sonogashira Protocol and Improved Synthesis of Free Fatty Acid 1 (FFA1) Receptor Agonists

A protocol for rapid and efficient Pd/Cu-catalyzed coupling of aryl bromides and iodides to terminal alkynes has been developed with use of 2-(di-tert-butylphosphino)-N-phenylindole (cataCXium PIntB) as ligand in TMEDA and water. The new protocol successfully couples substrates which failed with standard Sonogashira conditions, and enables an efficient general synthetic route to free fatty acid 1 (FFA1) receptor ligands from 3-(4-bromophenyl)-propionic acid.