A PASSE-PARTOUT FOR THE STABILIZATION OF HIGHLY POLAR UNSUPPORTED M-M' BONDS (M=TI,ZR,HF M'=FE,RU) AND ALPHA-ADDITION OF THE METAL NUCLEOPHILE ELECTROPHILE PAIRS TO AN ISOCYANIDE

The coordination of a novel type of tripodal amido ligand provides the key to the synthesis of stable M-M' (M = Ti, Zr, Hf; M' = Fe, Ru) het erobimetallic complexes, iMe(2)N(C(6)H(4)Me-4)}(3)M-M'(eta(5)-C5H5)(CO )(2)] 4-9, with unsupported metal-metal bonds and thus enables systema tic studies of these complexes; the crystal structures of the Ti-Fe (4 ) and Zr-Fe (6) complexes are reported, the latter being the first X-r ay structure of a compound containing a Zr-Fe bond; reaction of the M- M' complexes with methyl isocyanide leads to the immediate insertion i nto the metal-metal bond, a reaction which is analogous to alpha-addit ions to isocyanides.