Facile Synthesis of Z-Alkenes via Uphill Catalysis
摘要:
Catalytic access to thermodynamically less stable Z-alkenes has recently received considerable attention. These approaches have relied upon kinetic control of the reaction to arrive at the thermodynamically less stable geometrical isomer. Herein, we present an orthogonal approach which proceeds via photochemically catalyzed isomerization of the thermodynamic E-alkene to the less stable Z-isomer which occurs via a photochemical pumping mechanism. We consider two potential mechanisms. Importantly, the reaction conditions are mild, tolerant, and operationally simple and will be easily implemented.
Process for the production of chiral unsaturated alcohols in high
申请人:Eastman Chemical Company
公开号:US05886214A1
公开(公告)日:1999-03-23
The catalytic asymmetric hydrogenation of enol esters with a vinyllic or acetylenic substituent proceeds with extremely high enantioselectivity using a Rhodium-chiral bisphosphine catalyst. This is at variance with the hydrogenation of enol esters bearing a saturated substituent, which are hydrogenated with only marginal enantioselectivity under the same conditions.
Regiocontrolled allylsilane synthesis from secondary allylic alcohol derivatives
作者:Ian Fleming、Andrew P. Thomas
DOI:10.1039/c39850000411
日期:——
Unsymmetrical secondaryallylic acetates and urethanes react with the dimethyl(phenyl)silylcuprate reagent to give allylsilanes with fair to good regioselectivity.
Process for the production of chiral unsaturated alcohols in high optical purity
申请人:EASTMAN CHEMICAL COMPANY
公开号:EP0872467A1
公开(公告)日:1998-10-21
The catalytic asymmetric hydrogenation of enol esters with a vinyllic or acetylenic substituent proceeds with extremely high enantioselectivity using a Rhodium-chiral bisphosphine catalyst. This is at variance with the hydrogenation of enol esters bearing a saturated substituent, which are hydrogenated with only marginal enantioselectivity under the same conditions.