Redox properties of iridium complexes [Ir(eta(5)-C5Me5)(eta(5)-L)](+)
(1(+), L = C5H5; 2(+), L = C5Me5; 3(+), L = C9H7) were studied by cycl
ic voltammetry (CV). All three complexes can be reduced to 19-electron
radicals 1-3. The stability and reactivity of these radicals depend o
n the electronic and steric properties of the ligands. The mixture of
dimers Me5)Ir(mu-eta(4):eta(4)-C5H5C5Me5)Ir(eta(5)-C5H5)] (4a) and H5)
Ir(mu-eta(4):eta(4)-C5Me5C5Me5)Ir(eta(5)-C5H5)] (4b) was formed as a r
esult of reduction of 1(+) with Na/Hg in THF. Both chemical and electr
ochemical reduction of 2(+) gave the dimer 5)Ir(mu-eta(4):eta(4)-C5Me5
C5Me5)lr(eta(5)-C5Me5)] (5) in low yield. Reduction of 3(+) gave the t
etranuclear complex e5C5Me5)Ir(mu-eta(5):eta(4)-C9H7)Ir(eta(5)-C5Me5)]
(6).