Details

Autor(en) / Beteiligte

• Nguyen, Tuan‐Anh
• Daiann Sosa Carrizo, E.
• Cattey, Hélène
• Fleurat‐Lessard, Paul
• Roger, Julien
• Hierso, Jean‐Cyrille

Titel

Tetranuclear Dicationic Aurophilic Gold(I) Catalysts in Enyne Cycloisomerization: Cooperativity for a Dramatic Shift in Selectivity

Ist Teil von

• Chemistry : a European journal, 2022-05, Vol.28 (27), p.e202200769-n/a

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2022

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• In comparison to mononuclear gold Lewis acid catalysts, digold complexes and dual‐gold catalysis have illustrated a distinct and powerful potential for the activation of carbon‐carbon multiple bonds. Herein, this concept is pushed further by designing novel tetranuclear gold(I) dicationic complexes structurally supported by strongly stabilizing constraint diphosphinoferrocenyl ligands and attractive closed‐shell Au⋅⋅⋅Au aurophilic interactions. The use of a molecularly‐defined tetranuclear dicationic aurophilic gold(I) precatalyst for the selectivity‐challenging cycloisomerization of low‐substituted 1,6‐enynes favors the formation with high selectivity of strained azabicyclo[4.1.0]hept‐4‐enes – even in the complete absence of activating/orienting substituents on alkyne and olefin reactive functions. This selectivity is not achieved by the reported phosphine‐ and carbene‐stabilized mono‐ and dinuclear cationic gold(I) complexes, including the ones formed from the same ligands. More importantly this selectivity differs also from nanoparticles and heterogeneous gold catalysts reported to date. DFT studies correlated to experimental mechanistic investigations support an unprecedented “cluster‐like” reactivity from polynuclear cooperation at the origin of this peculiar selectivity where the aurophilic interactions preexist, and pre‐organize, gold cluster reactive intermediates. Towards specific “cluster‐like” reactivity? Ligands pre‐organizing gold centers in a constrained environment, assisted by aurophilic interactions, push further the selectivity not achieved by mono‐ and digold complexes from previously unseen cooperative tetragold catalysis.