Electronic interactions in [Ru3(mu3-R² CCC6H4-4-R¹)(mu -dppm)(mu-CO) (CO)7] (R¹ = NO2 and R² = Fc; R¹ = NO2, CN and R² = Ph)

The co-ordination of FcCCC6H4-4-NO2 (1) to a ruthenium carbonyl cluster to yield [Ru3(mu 3-FcCCC6H4-4-NO2) (mu-dppm)( mu-CO)(CO)7] (2) is reported. The cyclic voltammograms of these compounds and of the analogous clusters [Ru3(mu3 -eta2-C6 H5CCC6H4-4-R)(mu -dppm)(mu -CO)(CO)7] (R= H, 3; CN, 4; NO2, 5) allowed an evaluation of the electronic communications between the different redox sites (ferrocenyl and -NO2 groups, and Ru3 moiety) and an analysis of the relative electron donor-acceptor capabilities of each of the three redox centres that compose 2. Furthermore, the inertness of 2, compared with clusters 3-5 which loose CO readily was attributed to the interaction between the ferrocenyl group and the metallic frame.