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Updated: Jun 9, 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
Nucleophilic scandium carbene complexes
Marie Fustier1, Xavier F Le Goff, Pascal Le Floch
1Laboratoire Hétéroéléments et Coordination, UMR CNRS 7653 (DCPH), Département de Chimie, Ecole Polytechnique, 91128 Palaiseau Cedex, France.
Abstract:
Using a geminal dianion as precursor, a nucleophilic scandium carbene complex (2) has been synthesized by salt metathesis on ScCl(3)(THF)(3) in 52% isolated yield. The X-ray structure as well as an NBO analysis points to a double interaction between the carbon and the scandium atoms. Quantification of the electron density donation from the carbon to the metal center, from both σ and π symmetry orbitals, predicts a "nucleophilic carbene" behavior. Addition of benzophenone on complex 2 results in the formation of the expected alkene derivative and the trapping of a rare, μ(3)-oxo-Sc species via a "scandia-Wittig" reaction.
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