Samarium(II)-Iodide-Mediated Cyclizations in Natural Product Synthesis

SmI2 is a versatile reagent now widely used in organic chemistry. Despite the wealth of literature on the subject, the mechanisms of some SmI2-mediated reactions are still uncertain and the role of additives and cosolvents is poorly understood. This review covers the use of SmI2-mediated cyclization reactions in natural product synthesis. The use of the full armory of ring-forming reactions conducted by the reagent is outlined. Focus is on the most challenging targets, such as Taxol, gambierol, and diazonamide A.