title: Divergent Reactivity via Cobalt Catalysis: An Epoxide Olefination.
abstract: Cobalt salts exert an unexpected and profound influence on the reactivity of epoxides with dimethylsulfoxonium methylide. In the presence of a cobalt catalyst, conditions for epoxide to an oxetane ring expansion instead deliver homoallylic alcohol products, corresponding to a two-carbon epoxide homologation/ring-opening tandem process. The observed reactivity change appears to be specifically due to cobalt salts and is broadly applicable to a variety of epoxides, retaining the initial stereochemistry. This transformation also provides operationally simple access to enantiopure homoallylic alcohols from chiral epoxides without use of organometallic reagents. Tandem epoxidation-homologation of aldehydes in a single step is also demonstrated.
authors.affiliation: School of Chemical Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland , 23 Symonds Street, Auckland 1142, New Zealand.
authors.forename: Megan L
authors.initials: ML
authors.lastname: Jamieson
authors.affiliation: School of Chemical Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland , 23 Symonds Street, Auckland 1142, New Zealand.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Hume
authors.affiliation: School of Chemical Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland , 23 Symonds Street, Auckland 1142, New Zealand.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Furkert
authors.affiliation: School of Chemical Sciences and Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland , 23 Symonds Street, Auckland 1142, New Zealand.
authors.forename: Margaret A
authors.initials: MA
authors.lastname: Brimble