Facile Preparation of Functionalized 1-Substituted Cycloalkenes via an Iodine Atom Transfer Radical Addition–Elimination Process

An efficient and scalable two-step one-pot procedure for the preparation of cycloalkenes substituted with a functionalized alkyl side chain is reported. This method is based on a triethylborane-mediated iodine atom transfer radical addition (ATRA) of 1-iodoesters and related compounds to methylenecycloalkanes followed by treatment of the intermediate tertiary iodide with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to promote a selective endo elimination.