Porous graphitic carbon (PGC) high-performance liquid chromatography of diphosphine-bridged complexes with heteronuclear Au-M (M=Mn, Re) bonds

Summary The isocratic high-performance liquid chromatography of 1,1′-bis(diphenylphosphino)ferrocene (dppf), 1,1′-bis(diphenylphosphino)ruthenocene (dppr), bis(diphenylphosphino)methane (dppm) and triphenylphosphine (PPh₃)-substituted heterometallic Au-Mn or Au-Re carbonyl complexes is reported. A column packed with PGC (porous graphitic carbon) was used after preliminary experiments had shown that silica- and bonded-phase (silica-based) stationary phases were unsatisfactory for separation. The PGC column exhibited unique selectivity for the complexes studied. The mobile phases used were water-acetonitrile, dichloromethanehexane and tetrahydrofuran-hexane. The retention behaviour of the compounds was governed by the polar character and size of molecules, and influenced by metal-metal bond polarity. Separation of isomorphous structures with different metallocenyl moieties was achieved.