Trans-dichloro-piperazine-bis(ether-phosphine)ruthenium(II) complex of general formula Cl2Ru(h1-Ph2PCH2CH2OCH3)2(C4H10N2) 2 was made available in good yield through treating equimolar amounts of Cl2Ru(PÇO)2 complex 1 with piperazine as co-ligand. The hemilability ring open reaction of ether-phosphine in complex 1 to prepare complex 2 was monitored by 31P-NMR. The structure of complex 2 was confirmed byelemental analysis, IR, 31P-NMR 1H-NMR,13C-NMR, FAB-MS and UV-visible spectroscopy.