Copper(I) diphenylphosphinate is primarily used as a catalyst in various organic synthesis reactions. It is particularly effective in facilitating cross-coupling reactions, which are essential for forming carbon-carbon bonds in the production of pharmaceuticals, agrochemicals, and advanced materials. The compound is also employed in the synthesis of complex organic molecules, where its ability to stabilize intermediates and enhance reaction selectivity is highly valued. Additionally, it finds application in the development of luminescent materials and coordination polymers, contributing to advancements in optoelectronics and material science. Its role in catalysis and material synthesis makes it a versatile and important chemical in both industrial and research settings.