In contrast to selenenyl chlorides (RSeCl) or bromides (RSeBr), which are widely used in organic synthesis, the reactivity of selenenyl iodides (RSeI) remains largely unelucidated due to their instability. The thermodynamics of the reaction of RSeI with an olefin were investigated utilizing an isolable selenenyl iodide, BpqSeI, and the ΔH° value of its reaction with cyclohexene suggested analogous features of RSeI and I2 as electrophiles for their addition to olefins. Based on such characteristic thermodynamics, the efficient selenofunctionalization of olefins with external oxygen or nitrogen nucleophiles using BpqSeI was developed. In the presence of an appropriate additive, such as N-iodosuccinimide, various alcohols, a carboxylic acid, and aromatic amines were smoothly introduced into olefins to give the corresponding β-oxyselenides and β-aminoselenides in moderate to high yields.
