title: Enantioselective synthesis of (-)-dihydrocodeinone: a short formal synthesis of (-)-morphine.
abstract: [reaction: see text] The radical cyclization approach to the morphine alkaloids has been applied in an asymmetric synthesis of (-)-dihydrocodeinone. A chiral cyclohexenol (R-32), from the CBS reduction of the enone, is the source of chirality. The first key step, tandem closure in which stereochemistry is controlled by geometric constraints, (-)-15b --> (+)-16, was followed by an unprecedented reductive hydroamination, completing the synthesis of (-)-dihydroisocodeine ((-)-17) in 13 steps from commercially available materials.
authors.affiliation: Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA.
authors.forename: Kathlyn A
authors.initials: KA
authors.lastname: Parker
authors.forename: Demosthenes
authors.initials: D
authors.lastname: Fokas
mesh_terms: D006853:Hydrocodone / Q000138:chemical synthesis* / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D009020:Morphine / Q000737:chemistry*; D009022:Morphine Derivatives / Q000138:chemical synthesis / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D009022:Morphine Derivatives; D006853:Hydrocodone; D009020:Morphine