Gold-Catalyzed Synthesis of Furans and Furanones from Sulfur Ylides
作者:Xueliang Huang、Bo Peng、Marco Luparia、Luis F. R. Gomes、Luís F. Veiros、Nuno Maulide
DOI:10.1002/anie.201203637
日期:2012.8.27
A golden switch: Doubly stabilized sulfonium ylides can be coupled with alkynes in a gold‐catalyzed synthesis of heterocycles. This method hinges on a switch in the reactivity of the sulfur ylide resulting from the simple modification of the electron‐withdrawing moieties and leads to either furans or furanones bearing a quaternary center (see scheme).
Catalyst-Controlled Ring-Opening Cycloisomerization Reactions of Cyclopropenyl Carboxylates for Highly Regioselective Synthesis of Different 2-Alkoxyfurans
作者:Jie Chen、Shengming Ma
DOI:10.1002/asia.201000324
日期:2010.11.2
Differently substituted 2‐alkoxyfurans (2,3,4‐ or 2,3,5‐trisubstituted furans) were highlyregioselectively synthesized by means of the ring‐opening cycloisomerization of the same cyclopropenylcarboxylates with good yields in different solvents and excellent regioselectivity by using [Cu(acac)2] (acac=acetylacetonate) or [RuCl2(PPh3)3] as the catalyst, respectively. The structures of these two different