Re catalysis in one‐pot reactions: An atom‐economical, one‐pot strategy that involves alkyne deprotonation and a subsequent rhenium(V)‐catalysed Meyer–Schuster rearrangement of the alkynol to provide α,ß‐unsaturated enones in high yield has been developed (see scheme). Subsequent in situ hydride reduction or Diels–Alder reaction of the enones provided products in good‐to‐high overall yields.
[(NHC)AuCl]-catalyzed Meyer–Schuster rearrangement: scope and limitations
作者:Rubén S. Ramón、Nicolas Marion、Steven P. Nolan
DOI:10.1016/j.tet.2008.10.111
日期:2009.2
system allowing for the synthesis of a variety of α,β-unsaturated ketones has been developed. [(NHC)AuCl] (NHCN-heterocyclic carbene) in the presence of a silver(I) salt was found to catalyze the Meyer–Schuster rearrangement, leading to α,β-unsaturated ketones from easily accessible propargylic alcohols in high yields. Catalysis was performed in a 2:1 mixture of methanol and water at 60 °C and afforded