Oxidative addition of carbon-carbon bonds to gold
Résumé
The oxidative addition of strained C-C bonds (biphenylene, benzocyclobutenone) to DPCb (diphosphino-carborane) gold(I) complexes is reported. The resulting cationic organogold(III) complexes have been isolated and fully characterized. Experimental conditions can be adjusted to obtain selectively acyl gold(III) complexes resulting from oxidative addition of either the C(aryl)-C(O) or C(alkyl)-C(O) bond of benzocyclobutenone. DFT calculations provide mechanistic insight into this unprecedented transformation. Gold(I) complexes ([(DPCb)Au]+) readily insert into the four-membered rings of biphenylene and benzocyclobutenone. These transformations afforded well-defined cationic organogold(III) complexes that were isolated and fully characterized. [(DPCb)Au]+ is the only complex to cleave selectively either the C(aryl)-C(O) or the C(alkyl)-C(O) bond of benzocyclobutenone under kinetic/thermodynamic control. DPCb=diphosphinocarborane. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.