E-Phenylethenylboronic acid, also known as (E)-1-phenyl-1-ethenylboronic acid, is an organic compound with the chemical formula C8H9BO2. It is a colorless solid that is soluble in water and is commonly used as an intermediate in the synthesis of various organic compounds, particularly in the field of pharmaceuticals and agrochemicals. E-PHENYLETHENYLBORONIC ACID is a valuable building block for the construction of complex molecules due to its ability to undergo Suzuki-Miyaura cross-coupling reactions, which facilitate the formation of carbon-carbon bonds. Its structure features a phenyl group attached to a vinyl group, with a boronic acid functionality that can participate in various chemical transformations. E-Phenylethenylboronic acid is also known for its stability and reactivity, making it a popular choice in organic synthesis.