Three-Different-Component -Annulation Reactions: Ionic and Radical Cyclizations

Article abstract of DOI:10.1021/jo00294a029

One-carbon-atom Michael donors are used to initiate convergent and flexible <1+2+3>-hexannulations and <1+2+2>-pentannulations in which the initial nucleophilic carbon atom terminates the reaction sequence in an ionic fashion as an electrophilic center or in a carbon-centered radical fashion as a nucleophilic center.This protocol is used to prepare regiospecifically substituted bicyclic ketones and lactones and a cis-bicyclic tetrahydrofuran.