(Pentamethylcyclopentadienyl)Iridium Dichloride Dimer {[IrCp*Cl2]2}: A Novel Efficient Catalyst for the Cycloisomerizations of Homopropargylic Diols and N-Tethered Enynes
iridium dichloride dimer [IrCp*Cl2]2}-catalyzed hydroalkoxylation of bis-homopropargylicalcohols provides an efficient access to dioxabicyclo[2.2.1]ketals. The cycloisomerizations proceed under mild conditions, with low catalytic loadings and short reaction times. This new protocol involving an Ir(III) catalyst also promoted the cycloisomerization of nitrogen-tethered 1,6-enynes to give azabicyclo[4