Microbiological synthesis of optically active 3-deuterio-cycloalkanones
作者:Gerard Dauphin、Jean-Claude Gramain、Alain Kergomard、Michel F. Renard、Henri Veschambre
DOI:10.1039/c39800000318
日期:——
Optically active 3-deuterio-cyclopentanone and 3-deuterio-cyclohexanone have been prepared by microbiologicalreduction of 3-deuterio αβ-unsaturated cyclic ketones by Beauveriasulfurescens.
Scalable Total Synthesis of (−)-Triptonide: Serendipitous Discovery of a Visible-Light-Promoted Olefin Coupling Initiated by Metal-Catalyzed Hydrogen Atom Transfer (MHAT)
作者:Xianhe Fang、Nan Zhang、Si-Cong Chen、Tuoping Luo
DOI:10.1021/jacs.1c12525
日期:2022.2.9
An efficient and scalable total synthesis of (−)-triptonide is accomplished based on a metal-catalyzed hydrogenatom transfer (MHAT)-initiated radical cyclization. During the optimization of the key step, we discovered that blue LEDs significantly promoted the efficiency of reaction initiated by Co(TPP)-catalyzed MHAT. Further exploration and optimization of this catalytic system led to development
Origins of regio- and stereoselectivity in additions of phenylselenenyl chloride to allylic alcohols and the applicability of these additions to a simple 1,3-enone transposition sequence
作者:Dennis Liotta、George Zima、Manohar Saindane
DOI:10.1021/jo00346a022
日期:1982.3
Synthesis of 2-Quinuclidonium by Eliminating Water: Experimental Quantification of the High Basicity of Extremely Twisted Amides
作者:Tony Ly、Michael Krout、Don K. Pham、Kousuke Tani、Brian M. Stoltz、Ryan R. Julian
DOI:10.1021/ja067703m
日期:2007.2.1
The chemical properties of an extremely twisted amide are examined quantitatively for the first time. The predicted high basicity of 2-quinuclidonium is confirmed experimentally by measuring the gas-phase proton affinity using the extended kinetic method. Fragmentation of this molecule further reveals that the lack of resonance stabilization weakens the amide bond. Furthermore, a new route for synthesizing 2-quinuclidonium by eliminating water is demonstrated in the gas phase.
Base-catalyzed fragmentation of 2,3-dioxabicyclo[2.2.1]heptane, the bicyclic peroxide nucleus of prostaglandin endoperoxides: large secondary deuterium kinetic isotope effects