A series of gold(I) isonitrile complexes were prepared and converted to the corresponding diaminocarbene gold(I) complexes by reactions with primary and symmetrical secondary amines. Twelve crystal structure analyses of the gold(I) complexes could be obtained, in addition NMR studies allowed an analysis of the different diastereomers present in solution. In the gold-catalyzed phenol synthesis these complexes were very successful as pre-catalysts, reaching an unprecedented 3050 turnovers with a problematic substrate. Good conversions in the hydration of phenylacetylene could also be achieved.

The substrate scope, the mechanistic aspects of the gold-catalyzed oxazole synthesis, and substrates with different aliphatic, aromatic, and functional groups in the side chain were investigated. Even molecules with several propargyl amide groups could easily be converted, delivering di- and trioxazoles with interesting optical properties. Furthermore, the scope of the gold(I)-catalyzed alkylidene synthesis was investigated. Further functionalizations of these isolable intermediates of the oxazole synthesis were developed and chelate ligands can be obtained. The use of Barluenga's reagent offers a new and mild access to the synthetically valuable iodoalkylideneoxazoles from propargylic amides, this reagent being superior to other sources of halogens.

From palladium(II) or platinum(II) bis(isonitrile) complexes and from gold(I) isonitrile complexes, both easily available from simple precursors, the corresponding mono-N-heterocyclic carbene (NHC) complexes could be obtained selectively in good yields under very mild conditions. The reagents are simple b-chloroammonium salts in the presence of a weak base. Unsymmetric NHC complexes are accessible. Thus over only two steps from simple metal precursors a broad variety of NHC complexes is available, the method is ideal to quickly assemble catalyst libraries. The palladium complexes are active pre-catalysts in Suzuki cross-coupling even with the additional isonitrile ligand on palladium.