Allyl Complexes of Tungsten from the Rearrangement of Transient Cyclopropyl Precursors

Kyle Parker (1) , Stephane Labat (2) , Jean-Marc Sotiropoulos (2) , Karinne Miqueu (2) , Véronique Pimienta (3, 4) , Laure Vendier (1) , Michel Etienne (1)

1 LCC - Laboratoire de chimie de coordination
2 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux
3 IMRCP - Interactions moléculaires et réactivité chimique et photochimique
4 IMRCP - IDeAS - IMRCP - Interfaces Dynamiques et Assemblages Stimulables

This article explores the contrasting reactivity of cyclopropyl complexes of early transition metals. [Cp*W(NO)(CH2R)(c‐C3H5)] (R = SiMe3, Ph, t‐Bu) generated in THF solution from [Cp*W(NO)(CH2R)Cl] and [Mg(c‐C3H5)2(dioxane)x] readily rearrange to η3‐allyl derivatives [Cp*W(NO)(CH2R)(η3‐C3H5)] by an intramolecular ring opening reaction. Both direct and catalyzed pathways are revealed by kinetic studies. Computational modeling indicates the ring opening reaction is preferred on thermodynamic grounds for tungsten whereas kinetic products arising from β‐H abstraction reactions of cyclopropane are observed for related zirconium and niobium complexes reported previously. The energetic accessibility and the nature of the LUMO in the tungsten complexes promote distal CC bond cleavage in the cyclopropyl ring.

Keywords: Allyl ligands; Cyclopropyl ligands; Tungsten; Density functional calculations; Ring opening

Domains: Chemical Sciences

Kyle Parker, Stephane Labat, Jean-Marc Sotiropoulos, Karinne Miqueu, Véronique Pimienta, et al.. Allyl Complexes of Tungsten from the Rearrangement of Transient Cyclopropyl Precursors. European Journal of Inorganic Chemistry, 2019, 2019 (42), pp.4555-4563. ⟨10.1002/ejic.201900816⟩. ⟨hal-02309138⟩