Mass Spectrometry of Transition Metal π-Complexes. Part-Vll : A Study of the Behaviour of Some Ruthenocene Derivatives

School of Chemical and Physical Sciences, Kingston Polytechnic, Penrhyn Road, Kingston upon Thames KTI -2EE, U. K. The mass spectral fragmentation of (η-C5 H5)Ru(η-C5H4COR) (R-CH2,Ph) (I,II) and (η-C5H4 COCHO3)Ru(η-C5H4 COCHO3) (IlI) has been examined and compared with that of the ferrocene analogues. The higher metal-ligand bond strengths in the rutheno­cene derivatives are reflected in much more extensive fragmentation of the metal-bound ligands compared to the behaviour of the ferrocenes. The ion, (M-CH3)+ from (III) shows an unusual loss of two CO groups in a single step, a process believed to be under thermodynamic control and leading to [(C5H5)Ru(C5H5)