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The formation of stable, undistorted octahedral transition metal complexes which contain a trans-spanning bidentate ligand remains a synthetic challenge. The reported complexes are of the type trans-[Ru(Cl)(trpy){Ph2PC6H4CH2O(CO)Y(CO)OCH2C6H4PPh2}][PF6] [where trpy 4;= 4;2,2′∶6′,2″-terpyridine and Y 4;= 4;(CH2)3 4;= 4;C3SPAN, 6; (CH2)4 4;= C4SPAN, 7; or isophthalate 4;= 4;ISPAN, 8] and represent the first examples of trans-spanned transition metal complexes which display little bond angle distortion from octahedral geometry and also contain a bridging linkage which is stable towards oxidation, reduction and hydrolysis. These complexes were characterized by elemental analyses, cyclic voltammetry, conductivity and UV-VIS spectroscopy. COSY, HETCOR and variable temperature (1H and 13C) NMR spectra of the complexes are consistent with a flexible spanning linkage that does not demonstrate restricted rotation about either the P–Cipso or the Ru–P bonds while the X-ray crystal structure analysis of 7 showed that the spanning linkage is positioned to one side of the meridional chloride.