A Polysiloxide Complex with two Chromium(III) η2‐Superoxo Moieties. Issue 10 (12th November 2019)

• Record Type: Journal Article
• Authors: Wind, Marie‐Louise; Braun‐Cula, Beatrice; Schax, Fabian; Herwig, Christian; Limberg, Christian
• Is Part Of: Israel journal of chemistry. Volume 60:Issue 10/11(2020)
• Page Start: 1057
• Page End: 1060
• Publication Date: 2019-11-12
• Subjects: Chromium -- O−O activation -- siloxide -- superoxo; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/ijch.201900119
• Languages: English
• ISSNs: 0021-2148

Abstract

Abstract: The isolation and identification of intermediates formed in the course of the activation of dioxygen at transition metal centers reveals important mechanistic insights concerning such processes. We previously reported the reaction of the dinuclear Cr II complex [L2 Cr2 (MeCN)2 ][Li(MeCN)]2 (L=PhSi(OSiPh2 O − )3 ) (5 ) with dioxygen, which resulted in the formation of the Cr IV oxo complex [L2 Cr2 O2 ][Li(THF)2 ]2 (6 ), as the final room temperature stable product. Here we now report the isolation and characterization of an intermediate en route to 6, namely the dinuclear Cr III superoxo complex [L2 Cr2 (O2 )2 ][Li(MeCN)]2 (7 ). 7 is the first example of a structurally characterized dinuclear Cr III superoxo complex with two independent side‐on bound superoxo ligands. Reactivity studies outline the capability of this superoxo complex to activate weak O−H bonds. Abstract : A unique example of a dinuclear Cr III superoxo complex with two independent side‐on bound superoxo ligands is reported. This complex was identified as an intermediate in the reaction of a Cr II polysiloxide complex with dioxygen. Reactivity studies outline the capability of this superoxo complex to activate weak O−H bonds.