Multiple oxidative addition of Ph-2(C5H4N)PSe to [Ru-3(CO)(12)] - Structural characterization of [Ru-3(mu(3)-Se)(mu-PPh2)(2)(mu-C5H4N)(mu(3)-C5H4N)(CO)(6)] containing two differently metalated 2-pyridyl fragments

The ligand Ph-2(2-C5H4N)PSe undergoes multiple fragmentation by reaction wi th [Ru-3(CO)(12)] affording the 54-electron trinuclear complex [Ru3 (mu3-Se ) (mu -PPh2)(2) (mu -C5H4N) (mu (3)-C5H4N)(CO)(6)] (1) which does not conta in any Ru-Ru bond and is built up by a unique synergism of five bridging li gands. Complex 1 contains two bridging pyridyl groups: the first one connec ts two ruthenium atoms through sigma bonds and lies on the plane defined by the three metals; the second one is also sigma -bound to two ruthenium ato ms, and is nearly perpendicular to the metal plane in such a way that it ap pears to be involved in a weak a interaction with the third metal.