作者:Andrew L. Kocen、Maurice Brookhart、Olafs Daugulis
DOI:10.1039/c7cc04953f
日期:——
We report a method for palladium-catalysed chain-running isomerization of terminal and internal alkenes. Using an air-stable 2,9-dimethylphenanthroline-palladium catalyst in combination with NaBAr4 promoter, olefins are converted to the most stable double bond isomer at −30 to 20 °C. Silyl enol ethers are readily formed from silylated allylic alcohols. Fluorinated substituents are compatible with the
The three‐component free‐radical carbo‐alkenylation of electron‐richolefins has been studied, varying the substitution pattern in the alkene, in the radical precursor and in the final acceptor. New vinylsulfones were also prepared and their reactivity investigated. The scope and limitations of the process was established, and the reaction mechanism clarified using selected dienes as radical clocks
Reactions and characterization of allylic and related zirconium reagents (allenic and γ-alkoxyallylic zirconiums) generated by treatment of allylic and/or propargylic ethers with a zirconocene-butene complex (“Cp2Zr”) are described.
Preparation and regio- and diastereoselective reactions of allylic zirconium reagents from allylic ether derivatives
作者:Hisanaka Ito、Takeo Taguchi、Yuji Hanzawa
DOI:10.1016/s0040-4039(00)91605-8
日期:1992.3
Allylic zirconium reagents were generated by treating allylic ether derivatives with zirconocene “Cp2Zr”. The allylic zirconium reagents reacted with aldehydes in highly regio- and diastereoselective manner to give homoallylicalcohol compounds.
The stereoselectivity of some intermolecular nitronecycloadditions to alkenes featuring heterosubstituted allylic stereocenter is discussed and rationalized.