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The use of metal acetates has allowed the synthesis of NHC complexes without isolation of the free carbene. This route is very useful in cases where the metal acetates are readily available and has been used, for example, for the synthesis of bis(N-heterocyclic carbene) complexes of palladium(II). In the case of platinum, however, the corresponding acetate is not commercially available and is difficult to synthesize. Previously published syntheses require either an external base (e.g. NaOAc or KOtBu) or a transmetalation step. Here we present a new general synthetic pathway for platinum–bis(carbene) complexes using platinum(II) acetylacetonate as a commercially available metal precursor. Aromatic substituents greatly enhance the stability of the metal complexes against acidic media. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Reaction of in,in‐phosphite 1with thiophosphoryl azide 2affords in,in‐dithiophosphate 3, in,in‐thiophosphate–imidophosphate 4, and in,in‐phosphite–imidophosphate 5. Compounds 4and 5are the first examples of the modification of in‐bridgehead positions in macrobicyclic compounds with groups larger than methyl. The benzaldehyde arms of the in‐substituent in 4and 5jut out of the cage bars. In 4they are trapped between the macrocyclic arms to give the NMR spectra of a Cs‐symmetric solution‐state structure. In contrast, in 5the benzaldehyde arms can move between the gaps of the cage. This results in 1H and 13C NMR spectra which are consistent for a compound with C3vsymmetry. In,out‐diimidophosphate 7is obtained in moderate yield by reaction of in,out‐phosphite 6with thiophosphoryl azide 2. Its in‐benzaldehyde moieties are not fixed between the cage arms, but can freely move from one gap to the next as is indicated by NMR measurements.