Ruthenium carbonyl clusters derived from pyrazolyl substituted diphosphazanes: Crystal and molecular structure of a triruthenium cluster featuring a triply bridging μ3-η1:η1:η1 coordination mode of pyrazolate moiety

The radical initiated reactions of Ru3(CO)12 with pyrazolyl substituted diphosphazanes Ph2PN(R)PPh(N2C3HMe2-3,5) [R = (S)-*CHMePh (1) or CHMe2 (2)] proceed via P–N(pyrazole) bond rupture resulting in the formation of phosphido clusters, [Ru3(CO)5(μsb-CO)2(μ3-N,N′-η1:η1:η1-N2C3HMe2-3,5){μ-P,P′-Ph2PN(R)PPh}] [R = (S)-*CHMePh (3) or CHMe2 (4)]. The pyrazolate moiety adopts an unusual triply bridging μ3-η1:η1:η1-mode of coordination in these clusters.