oiodophenol

Iodophenol refers to any monoiodinated derivative of phenol, in which a single iodine atom substitutes a hydrogen on the benzene ring. The three common isomers are 2-iodophenol (ortho), 3-iodophenol (meta), and 4-iodophenol (para). The general formula is C6H5IO. The hydroxyl group in phenol directs electrophilic iodination to the ortho and para positions, with the meta isomer typically arising under specific conditions or from alternative synthetic routes.

Synthesis of iodophenols is usually accomplished by electrophilic iodination of phenol or its derivatives. Iodine in combination with an oxidant (such as iodic acid or hydrogen peroxide) generates the active iodine species that substitutes a ring hydrogen. The ortho and para isomers are generally favored; achieving the meta isomer often requires indirect routes, such as iodination of a prefunctionalized substrate or subsequent rearrangement. Protective group strategies and modern palladium- or copper-catalyzed C–H iodination methods can also be employed to access specific isomers.

Properties of iodophenols vary with isomer and substitution pattern. They are typically solid at room temperature, with limited water solubility and relatively high molecular weight due to the iodine atom. The aryl–iodine bond is a reactive handle in further transformations, making iodophenols valuable intermediates in organic synthesis.

Applications include use as intermediates in pharmaceutical and agrochemical synthesis, as well as dyes and specialty materials. The C–I bond readily participates in cross-coupling reactions (such as Suzuki and Sonogashira), enabling construction of more complex molecules. Safety considerations include irritation of skin and eyes and the need for proper handling and disposal of iodine-containing compounds.