(Pentamethylcyclopentadienyl)Iridium Dichloride Dimer {[IrCp*Cl2]2}: A Novel Efficient Catalyst
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under investigation in our laboratory and will be re-
ported in due course.
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Experimental Section
Representative Procedure for [IrCp*Cl2]2-Catalyzed
Cycloisomerization of Bis-homopropargylic Alcohols
ACHTUNGTRENNUNG[IrCp*Cl2]2 (0.002 mmol) was dissolved in dry DCE (1 mL)
under an argon atmosphere. A solution of bis-homopropar-
gylic alcohol 1a (0.2 mmol) in dry DCE (1 mL) was added.
The mixture was stirred at room temperature for 30 min
then filtered through a short pad of celite. Removal of the
solvent under reduced pressure afforded product 2a in quan-
titative yield.
Representative Procedure for [IrCp*Cl2]2-Catalyzed
Cycloisomerization of Nitrogen-Tethered 1,6-Enynes
ACHTUNGTRENNUNG[IrCp*Cl2]2 (0.01 mmol) was dissolved in dry DCE (1 mL) at
room temperature under an argon atmosphere. A solution
of nitrogen-tethered 1,6-enyne 3a (0.2 mmol) in dry DCE
(1 mL) was added. The mixture was stirred at reflux for 3 h.
After cooling to room temperature, the solution was filtered
through a short pad of silica gel. The solvent was removed
under vacuum and the residue was purified by flash chroma-
tography over silica gel (AcOEt:pentane 5:95) affording
product 4a in 55% yield.
Acknowledgements
Authors thank the MRES, the CNRS, the IUF, the ANR Blan
0302 “Allꢀnes” and Rꢁgion IDF for financial support of this
project.
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