Pure Appl. Chem., 2011, Vol. 83, No. 3, pp. 507-518
http://dx.doi.org/10.1351/PAC-CON-10-09-06
Published online 2011-01-18
New samarium diiodide-induced cyclizations
Abstract:
Samarium diiodide (SmI2) smoothly promotes the cyclizations of suitably substituted carbonyl compounds with styrene subunits leading to benzannulated cyclooctenes. The intramolecular samarium ketyl addition to arene or hetarene moieties enables a new, efficient, and highly stereoselective entry to dearomatized products such as hexahydronaphthalenes, steroid-like tetra- or pentacyclic compounds, or dihydroindole derivatives. The usefulness of the developed SmI2-induced cyclization method was demonstrated by the shortest formal total synthesis of the alkaloid strychnine.
Keywords
alkenes; alkynes; arenes; cyclooctene derivatives; dearomatization; hetarenes; hexahydronaphthalenes; indoles; ketyls; natural products; samarium diiodide; steroid-like compounds; strychnine.