A highly luminescent octanuclear gold(i) carbide cluster

Abstract

The ligand [{Me₃SiCCC(NDipp)₂}Li(thf)₃] (Dipp = 2,6-diisopropylphenyl) was used for salt metathesis reactions with [AuCl(tht)] (tht = tetrahydrothiophene) to obtain the dinuclear alkyne functionalized bisamidinate [{Me₃SiCCC(NDipp)₂}₂Au₂]. This compound serves as a building block for the polynuclear carbide bridged gold(I) amidinate complex [Au₈{μ₃-(η¹:η²-CC)}₂(Me₃SiCCC(NDipp)₂)₄(tht)₂], which is the first gold(I) complex with a μ₃-η¹:η² carbide coordination. Both gold(I) compounds show distinct aurophilic interactions and are remarkably stable at ambient conditions. Photophysical investigations revealed intense luminescence with notable high quantum yields both in the solid state and in solution.