Smaller, faster, better: modular synthesis of unsymmetrical ammonium salt-tagged NHC–gold(<scp>i</scp>) complexes and their application as recyclable catalysts in water
作者:Katrin Belger、Norbert Krause
DOI:10.1039/c5ob01286d
日期:——
Facile access towards a small library of unsymmetrical ammonium salt-tagged N-heterocyclic carbene gold(I) complexes is described, and their application as recyclable catalysts in cyclization reactions of acetylenic carboxylic acids and amides to lactones and lactams, respectively, in aqueous media is demonstrated. Catalyst 1ab was applied in the synthesis of 2-epi-clausemarine A (16).
Bismuth-catalyzed Intramolecular Hydro-oxycarbonylation of Alkynes
作者:Kimihiro Komeyama、Keita Takahashi、Ken Takaki
DOI:10.1246/cl.2008.602
日期:2008.6.5
Bi(OTf)3 was found to be a good catalyst for intramolecular addition of carboxylic acids to alkynes (hydro-oxycarbonylation), which afforded the corresponding 5- and 6-membered lactones in moderate...