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Updated: Aug 6, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
A convenient and genuine equivalent to HZrCp2Cl generated in situ from ZrCp2Cl2-DIBAL-H
Zhihong Huang1, Ei-ichi Negishi
1Herbert C. Brown Laboratories of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084, USA.
Abstract:
[reaction: see text] Slow addition of 1 equiv of (i)Bu2AlH to ZrCp2Cl2 in THF provides a convenient route to either HZrCp2Cl-(i)Bu2AlCl (Reagent I) or HZrCp2Cl (Reagents II and III). The latter represents a highly convenient route to genuine HZrCp2Cl, while Reagent I is useful for regio- and stereoselective conversion of 1- and 2-alkynes into (E)-1-iodo-1-alkenes and (E)-2-iodo-2-alkenes, respectively.
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