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Updated: Apr 28, 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
Functionalization of a cyclo-P₅ ligand by main-group element nucleophiles
Eric Mädl1, Mikhail V Butovskii, Gábor Balázs
1University of Regensburg, Institut für Anorganische Chemie, 93040 Regensburg (Germany).
Abstract:
Unprecedented functionalized products with an η(4)-P5 ring are obtained by the reaction of [Cp*Fe(η(5)-P5)] (1; Cp*=η(5)-C5Me5) with different nucleophiles. With LiCH2SiMe3 and LiNMe2, the monoanionic products [Cp*Fe(η(4)-P5CH2SiMe3)](-) and [Cp*Fe(η(4)-P5NMe2)](-), respectively, are formed. The reaction of 1 with NaNH2 leads to the formation of the trianionic compound [{Cp*Fe(η(4)-P5)}2N](3-), whereas the reaction with LiPH2 yields [Cp*Fe(η(4)-P5PH2)](-) as the main product, with {[Cp*Fe(η(4)-P5)]2PH}(2-) as a byproduct. The calculated energy profile of the reactions provides a rationale for the formation of the different products.
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