Bromination of Binor‐S

Abstract Bromination of binor‐S resulted in a mixture of products containing several pairs of isomers. Three major processes were found to be involved in the reaction mechanism, i.e., bromination, hydrobromination, and dehydrobromination. The structures of nine compounds derived from dibromide 6 were identified by spectroscopic methods. Yields between isomers were rationalized by comparison of their relative strain energies calculated by force field model (MM2). The crystal structures of a tribromide (9) and a pentabromide (15) were solved by X‐ray diffraction analyses. Their crystal packing patterns indicated the existence of attractive interactions among the bromine atoms.