Electrophilic selenium, selenocyclizations

The most important progress made in the last ten years in the production of new electrophilic selenium reagents as well as in their reactivity towards unsaturated compounds are presented and discussed. Several new selenium-pr omoted, ring-closure reactions are illustrated and the factors controlling the selectivity of the cyclization process are discussed. One-pot selenenyl ation-deselenenylation sequences, which occur using only catalytic amounts of the organoselenium reagents, are presented. Finally, the efficient asymm etric syntheses, which are carried out with the recently described chiral n on-racemic electrophilic selenenylating agents, are also surveyed.