Syntheses of selectively fluorinated cyclodecenones: the first deployment of the neutral oxy-Cope rearrangement in organofluorine chemistry.
Metallated haloalkenes were used to open epoxides in moderate to good yield. The homoallylic alcohols obtained underwent Swern oxidation to afford three gamma,gamma-difluorinated beta,gamma-enones, which reacted with either vinyllithium,2-lithio-2H-dihydropyran or another metallated haloalkene to afford substituted trans-1,2-divinylcyclohexanols of different degrees of stability. These intermediates underwent neutral thermal oxy-Cope rearrangements when heated in xylene in Ace tubes. The first-formed enols ketonised without loss of HF to afford a range of cyclodecenones in moderate to good yield; X-ray crystallography was used extensively for product characterisation. All substrates rearranged more rapidly than a cis/trans mixture of 1,2-divinylcyclohexanols.
DiMartino
Gianluca
G
School of Chemical Sciences, University of Birmingham, Edgbaston, UK.
Hursthouse
Michael B
MB
Light
Mark E
ME
Percy
Jonathan M
JM
Spencer
Neil S
NS
Tolley
Malcolm
M
D018360:Crystallography, X-Ray; D004852:Epoxy Compounds / Q000138:chemical synthesis / Q000737:chemistry; D005461:Fluorine / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism
D004852:Epoxy Compounds; D006571:Heterocyclic Compounds; D006845:Hydrocarbons, Fluorinated; D005461:Fluorine