4-Isobutoxyphenylboronic acid (contains varying amounts of anhydride) is primarily used in organic synthesis, particularly in Suzuki-Miyaura cross-coupling reactions, where it acts as a key reagent for forming carbon-carbon bonds. Its boronic acid group enables efficient coupling with aryl halides, making it valuable in the production of pharmaceuticals, agrochemicals, and advanced materials. Additionally, it is utilized in the development of sensors and diagnostic tools due to its ability to interact with diols and other biologically relevant molecules. The presence of the isobutoxy group enhances its solubility and stability in various reaction conditions, broadening its applicability in industrial and research settings, including the development of polymers and fluorescent compounds.