Iodocyclization Reactions for the Desymmetrization of Cyclohexa-1,4-dienes
作者:M. Butters、M. C. Elliott、J. Hill-Cousins、J. S. Paine、J. K. E. Walker
DOI:10.1021/ol701492g
日期:2007.8.1
Fifteen examples are presented showing that various modes of cyclization (5-endo, 5-exo, 6-endo, 6-exo, and 7-endo) can be used for the desymmetrization of cyclohexa-1,4-dienes. All take place with complete diastereocontrol and good yield.
Nickel-Catalyzed Asymmetric Kumada Cross-Coupling of Symmetric Cyclic Sulfates
作者:Meredith S. Eno、Alexander Lu、James P. Morken
DOI:10.1021/jacs.6b03384
日期:2016.6.29
Nickel-catalyzed enantioselective cross-couplings between symmetric cyclic sulfates and aromatic Grignard reagents are described. These reactions are effective with a broad range of substituted cyclic sulfates and deliver products with asymmetric tertiary carbon centers. Mechanistic experiments point to a stereoinvertive SN2-like oxidative addition of a nickel complex to the electrophilic substrate