Synthesis of triarylborane-centered N-heterocyclic carbene cages with tunable photophysical properties.

Triarylborane-based discrete metal-carbene supramolecular cages [M 3 (1) 2 ](PF 6 ) 3 (M = Ag, Au) were synthesized and characterized. The new hexacarbene assemblies show a significant solvatochromic effect in solvents of different polarity. Furthermore, the reversible fluoride binding property of [Au 3 (1) 2 ](PF 6 ) 3 was investigated by UV-vis absorption and fluorescence titrations. This work holds promise for future developments in the area of highly emissive and stimulus-responsive NHC-metal assemblies.