Synthetic Potentialities of Alkyl and Aryl Cyclopropylidenealkyl Sulfides: Access to 1-(Arylthio)vinylcyclopropanes by a 1,3-Shift of an Arylthio Group
[EN] ASYMMETRIC ELECTROPHILIC FLUORINATION USING AN ANIONIC CHIRAL PHASE-TRANSFER CATALYST<br/>[FR] FLUORATION ÉLECTROPHILE ASYMÉTRIQUE UTILISANT UN CATALYSEUR DE TRANSFERT DE PHASE CHIRAL ANIONIQUE
申请人:UNIV CALIFORNIA
公开号:WO2013096971A1
公开(公告)日:2013-06-27
The discovery of distinct modes of asymmetric catalysis has the potential to rapidly advance chemists' ability to build enantioenriched molecules. As an example, the use of chiral cation salts as phase-transfer catalysts for anionic reagents has enabled a vast set of enantioselective transformations. A largely overlooked analogous mechanism wherein a chiral anionic catalyst brings a cationic species into solution is itself a powerful method. The concept is broadly applicable to a number of different reaction pathways, including to the enantioselective fluorocyclization of olefins, and dearomatization of aromatic systems with a cationic electrophile-transferring (e.g., fluorinating) agent and a chiral phosphate catalyst. The reactions proceed in high yield and stereoselectivity. The compounds and methods of the invention are of particular value, especially considering the scarcity of alternative approaches.
Electronic and Steric Control of Regioselectivities in Rh(I)-Catalyzed (5 + 2) Cycloadditions: Experiment and Theory
作者:Peng Liu、Lauren E. Sirois、Paul Ha-Yeon Cheong、Zhi-Xiang Yu、Ingo V. Hartung、Heiko Rieck、Paul A. Wender、K. N. Houk
DOI:10.1021/ja103253d
日期:2010.7.28
The first studies on the regioselectivity of Rh(I)-catalyzed (5 + 2) cycloadditions between vinylcyclopropanes (VCPs) and alkynes have been conducted experimentally and analyzed using density functional theory (DFT). The previously unexplored regiochemical consequences for this catalytic, intermolecular cycloaddition were determined by studying the reactions of several substituted VCPs with a range