Polycarbon ligand chemistry: Electronic interactions between a mononuclearruthenium fragment and a cobalt-carbon cluster core

The preparation, characterization, and electrochemical response of the comp lexes Co-2(mu-Me3SiC=CC2C=CSiMe3)(CO)(4)(dppm) (2) and Co-2(mu-Me3SiC2C=CC= CSiMe3)(CO)(4)(dppm) (3) are described. Metalation of one of the pendant al kynyl groups in each complex has been achieved, yielding Co-2{mu-Me3SiC=CC2 C=C[Ru(PPh3)(2)Cp]}(CO)(4)(dppm)(4) and Co-2{mu-Me3SiC2C=CC=C[Ru(PPh3)(2)Cp ]}(CO)(4)(dppm) (5). The spectral and electrochemical properties of the het erometallic complexes indicate a significant electronic interaction between the mononuclear fragment and the metallocarbon cluster core. The electroni c structure of these compounds has been modeled using DFT, ZINDO, and ELF c alculations, and an explanation of the nature of the electronic interaction between the heterometallic fragments is presented.