In the past few decades, mechanistic studies and various trials have been performed to achieve new designs for the Sonogashira reaction that do not involve the use of a copper cocatalyst. Researchers are working to develop new designs to allow the reaction to be performed in aerobic conditions, which cause homocoupling when used with the current reaction procedure. These new procedures are called Copper-free Sonogashira reactions and are being produced through the use of many different modifications to the original procedure. One example of a modification for these Copper-free reactions is the use of Pyrrolidine as a base with a Platinum catalyst (PdCl2 was used). This procedure was performed in water in an aerobic environment at 50° C and produced only trace amounts of the undesired homocoupling product; therefore, it did not react as drastically to the aerobic conditions. The reaction can be seen below: