Facile synthesis of unsaturated lactones via intramolecular Wittig reaction
作者:Pradeep Kumar、K. Saravanan
DOI:10.1016/s0040-4020(97)10428-8
日期:1998.3
The phosphoranes 3 formed from the reaction of a variety of keto alcohols 1 and (triphenylphosphoranylidene)ethenone 2 undergo intramolecular Wittig cyclization to afford the unsaturated lactones in moderate yields.
Functionalized phosphine ligands in transition metal-catalysed organic synthesis. Nickel(0)-catalysed cycloaddition of terminally unsubstituted diynes and carbon dioxide to bicyclic 2-pyrones
作者:Tetsuo Tsuda、Shohei Morikawa、Takeo Saegusa
DOI:10.1039/c39890000009
日期:——
A functionalized trialkylphosphine ligand (1a) containing a pyridyl group has effected the Ni(0)-catalysed cycloaddition of terminally unsubstituted diynes with CO2 to give bicyclic 2-pyrones, for which ordinary trialkylphosphine ligands are not effective.