SPLITTING OF DIAZENE AND DIPHOSPHENE LIGANDS IN CLUSTER-EXPANSION

The mu-E(2)R(2) bridged complexes Fe-2(CO)(6)(N(2)Ph(2)) (1a) and Fe-2(CO)(6)(P(2)(t)Bu(2)) (1b) undergo cluster expansion, with Fe-2(CO)(9) in hexane, to form the mu(3)-eta(2) bridged clusters Fe-3(CO)(9)(N(2)Ph(2)) (2a) and Fe-3(CO)(9)(P(2)(t)Bu(2)) (2b). Both clusters 2 are unstable in solution, being converted quantitatively with N-N or P-P cleavage into the bis-mu(3) bridged clusters Fe-3(CO)(9)(NPh)(2) (3a) and Fe-3(CO)(9)(P(t)Bu)(2) (3b) respectively.