title: Lactone radical cyclizations and cyclization cascades mediated by SmI2-H2O.
abstract: Unsaturated lactones undergo reductive radical cyclizations upon treatment with SmI(2)-H(2)O to give decorated cycloheptanes in a single highly selective operation during which up to three contiguous stereocenters are generated. Furthermore, cascade processes involving lactones bearing two alkenes, an alkene and an alkyne, or an allene and an alkene allow "one-pot" access to biologically significant molecular scaffolds with the construction of up to four contiguous stereocenters. The cyclizations proceed by the trapping of radical anions formed by electron transfer reduction of the lactone carbonyl.
authors: School of Chemistry, University of Manchester, Manchester, United Kingdom.
authors: Dixit
authors: D
authors: Parmar
authors: Hiroshi
authors: H
authors: Matsubara
authors: Kieran
authors: K
authors: Price
authors: Malcolm
authors: M
authors: Spain
authors: David J
authors: DJ
authors: Procter
mesh_terms: D000475:Alkenes / Q000737:chemistry; D000480:Alkynes / Q000737:chemistry; D003500:Cyclization; D007454:Iodides / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry*; D010084:Oxidation-Reduction; D012493:Samarium / Q000737:chemistry*; D013237:Stereoisomerism; D014867:Water / Q000737:chemistry*
chemical_list: D000475:Alkenes; D000480:Alkynes; D007454:Iodides; D007783:Lactones; D014867:Water; D012493:Samarium; C409809:samarium diiodide