2009, Haas, Thomas

Carbene complexes of chromium and tungsten are easily accessible and the variety of the coligand sphere and the carbene offer a wide range of reaction possibilities and synthetic potential. Allenylidene complexes as higher cumuloges of carbene complexes can also be obtained and derived in various ways. The effect of the change in the substitution pattern on the properties of those complexes is yet only rarely examined.
This work is firstly about new ways to derivate pentacarbonyl(allenylidene) complexes of chrom and tungsten, their properties and the possibility of creating polynuclear complexes connecting the metal centers by means of a common pi system.
Secondly, two ways of creating new heteroatom-substituted allenylidene complexes of nickel are introduced. The properties of the nickel allenylidene complexes are compared to those of the corresponding chromium complexes.