Abstract The chemo-and regioselectivity of the radical cyclization induced by titanocene chloride of a series of epoxyalkenes and another of unsaturated epoxyketones are investigated. 5-Exo and 6-exo cyclizations are the main processes with epoxyalkenes. 3-Exo and 4-exo cyclizations onto the carbonyl group and 6-exo and 8-endo onto the carbon- carbon double bond are the preferred processes with epoxyenones. A tandem reaction, 6- ...