Osmium complexes isocyanide

This proton transfer reaction is not fast, and it is suggested that this may be a more complicated reaction than was anticipated, perhaps occurring by initial addition of OH or OR to the metal followed by H2O or ROH expulsion. In support of this is the isolation of a complex Os(CO)-(CNC6H4CH3)(PPh3)2(H)OR from an analogous reaction sequence. (This is the only reference yet to any osmium carbonyl-isocyanide chemistry.)... 

An additional report on an osmium isocyanide complex is found in conference abstracts 78). 

Some interesting chemistry has appeared relating to the ability of the isocyanide ligand to stabilize unusual oxidation states. A series of palladium metal - metal bonded complexes has been synthesized by redox reactions involving two metal complexes in different formal oxidation states (33 -35). Similar ruthenium(I) and osmium(I) dimers have been prepared by an unusual homolytic fission of a ruthenium-carbon bond (36) or by singleelectron oxidation of Os(CNXylyl)5 (18). 

There are several other methods for the synthesis of carbene complexes of osmium. The reaction of a nucleophile with isocyanide complexes can result in the formation of osmium carbene complexes. Certain electron-rich alkenes add to osmium to form carbene complexes. For example. 

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