Polarized Complexes Obtained by Regiospecific Substitution of a CN Group in Ru{CCC(CN)C(CN)₂}(dppe)Cp* (Cp* = η-C₅Me₅)

The complex Ru­{CCC­(CN)C­(CN)₂}­(dppe)­Cp* (1), containing the new tricyanovinylethynyl (3,4,4-tricyanobut-3-en-1-ynyl) ligand, undergoes ready substitution of the 3-cyano group by nucleophiles (Nu) such as H, Me, Prⁱ, Bu, Bu^t, mesityl, OMe, OBu^t, OCH₂CHCH₂, NHEt, NEt₂, and PPh₂ to give Ru­{CCC­(Nu)C­(CN)₂}­(dppe)­Cp*. The X-ray diffraction structures of several of the resulting complexes are reported and, for the mesityl and PPh₂ products, show that isomerization to the 3,5-dimethylbenzyl and oxidation to the phosphine oxide have respectively occurred.