Brønsted Base-Catalyzed Transformation of α,β-Epoxyketones Utilizing [1,2]-Phospha-Brook Rearrangement for the Synthesis of Allylic Alcohols Having a Tetrasubstituted Alkene Moiety
stereoselective transformation of α,β-epoxyketones into alkenylphosphates having a hydroxymethyl group on the β-carbon was established by utilizing the [1,2]-phospha-Brook rearrangement under Brønsted base catalysis. The reaction involves the catalytic generation of an α-oxygenated carbanion located at the α-position of an epoxide moiety through the [1,2]-phospha-Brook rearrangement and the following
Stereospecific Construction of Chiral Tertiary and Quaternary Carbon by Nucleophilic Cyclopropanation with Bis(iodozincio)methane
作者:Kenichi Nomura、Seijiro Matsubara
DOI:10.1002/asia.200900289
日期:2010.1.4
The reaction of a ketone having a leaving group at the α‐position, such as α,β‐epoxy ketone or α‐sulfonyloxy ketone, with bis(iodozincio)methane affords a zinc alkoxide of cyclopropanol. The reaction proceeds by nucleophilic addition of the dizinc to the carbonyl group and a sequential intramolecular nucleophilic substitution of the introduced iodozinciomethyl group to the adjacent electrophilic carbon
A New Zincate-Mediated Rearrangement Reaction of 2-(1-Hydroxyalkyl)-1-alkylcyclopropanol
作者:Kenichi Nomura、Seijiro Matsubara
DOI:10.1002/chem.200901054
日期:2010.1.11
A novel rearrangement of 2‐(1‐hydroxyalkyl)‐1‐alkylcyclopropanol has been found. It proceeds in the presence of a catalytic amount of organozinc ate complex to give vic‐diols. The rearrangement can be applied to various types of 2‐(1‐hydroxyalkyl)‐1‐alkylcyclopropanol, which can be easily prepared from the corresponding α,β‐epoxyketones and bis(iodozincio)methane. When bicyclo[13.1.0]pentadecane‐1
Preparation of proximal β-hydroxy silyl enol ethers from α,β-epoxyketones using silyllithium reagents
作者:Heather K. Baker、Aaron M. Hartel
DOI:10.1016/j.tetlet.2009.04.085
日期:2009.7
stereoselective preparation of proximal β-hydroxy silyl enol ethers from α,β-epoxyketones using silyllithium reagents has been developed. The reaction is believed to proceed via Brook rearrangement assisted by opening of the adjacent epoxide. A number of α,β-epoxyketones were reacted with methyldiphenylsilyllithium to form the corresponding proximal β-hydroxy silyl enol ethers in good to excellent yield and excellent
Zincate-mediated rearrangement reaction of 2-(1-hydroxyalkyl)-1-alkylcyclopropanol
作者:Kenichi Nomura、Seijiro Matsubara
DOI:10.1039/b901043b
日期:——
A rearrangement of lithium alkoxide of 2-(1-hydroxyalkyl)-1-alkylcyclopropanol into lithium alkoxide of vic-diol was mediated with an organozincate complex.