Trinuclear and Tetranuclear Ruthenium Carbonyl Clusters Derived from Indenylphosphines: Cleavage of C−H and C−P Bonds

Thermal treatment of Ru3(CO)12 with equimolar amounts of (1H-inden-3-yl)diphenylphosphine and (1H-inden-2-yl)diphenylphosphine in octane gave two isomeric trinuclear ruthenium clusters Ru3(μ2-H)(μ3-3-Ph2PC9H6)(CO)9 (1) and Ru3(μ2-H)(μ3-2-Ph2PC9H6)(CO)9 (2), respectively, via a C−H bond cleavage. Heating either 1 or 2 in octane afforded the trinuclear and tetranuclear ruthenium clusters Ru3(μ3-PPh)(μ3-C9H6)(CO)9 (3) and Ru4(μ4-PPh)(μ4-C9H6)(CO)11 (4) via double C−P bond cleavage. Thermal treatment of Ru3(CO)12 with (4,7-dimethyl-1H-inden-3-yl)diphenylphosphine in octane gave trinuclear ruthenium cluster Ru3(μ2-H)(μ3-3-Ph2PC11H10)(CO)9 (5) via a C−H bond cleavage. Heating 5 in octane afforded a trinuclear ruthenium cluster Ru3(μ3-PPh)(μ3-C11H10)(CO)9 (6) and two isomeric tetranuclear ruthenium clusters Ru4(μ3-PPh)(μ2-η5:η1-C11H10)(CO)11 (7) and [Ru4(μ4-PPh)(μ4-C11H10)(CO)11] (8) via double C−P bond cleavage. Thermal treatment of Ru3(CO)12 with (3,4,7-trimethyl-1H-inden-1-yl)diphenylphosphine in toluene afforded two trinuclear ruthenium clusters Ru3(μ2-H)2(μ3-3-Ph2PC12H11)(CO)8 (9) via both sp3 and sp2 C−H bond cleavage and Ru3(μ2-PPh2)(μ3-η2:η2:η5-C12H13)(CO)6 (10) via a C−P bond cleavage. Thermal treatment of Ru3(CO)12 with (3-methyl-1H-inden-1-yl)diphenylphosphine in toluene afforded a trinuclear ruthenium cluster Ru3(μ2-H)(μ3-3-Ph2PC10H8)(CO)9] (11) via a C−H bond cleavage. The molecular structures of complexes 1−5 and 7−11 have been determined by single-crystal X-ray diffraction analysis.