Large bite bisphosphite ligand, 2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 (2), is obtained by reacting chlorophosphite, {-OC 10 H 6 (μ-S)C 10 H 6 O-}PCl (1) with 2,6-pyridinedimethanol in presence of triethylamine.Treatment of 2 with aqueous solution of H 2 O 2 or elemental sulfur resulted in the formation of bis(oxide) or bis(sulfide) derivatives, 2,6-C 5 H 3 N{CH 2 OP(E)(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 (3, E=O; 4, E=S) in quantitative yield.The 10-membered cationic chelate complex, [RuCl(η 6 -C 10 H 14 )η 2 -2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 -κP,κP]Cl (5) is produced in the reaction between [Ru(p-cymene)(μ-Cl)(Cl)] 2 and bisphosphite 2, whereas the neutral chelate complex, cis-[Rh(CO)Cl{2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 (μ-S)C 10 H 6 O–)} 2 }-κP,κP] (6) is isolated in the reaction of 2 with 0.5 equiv.of [Rh(CO) 2 Cl] 2 .Compound 2 on treatment with M(COD)Cl 2 (M=Pd, Pt) produce the chelate complexes, [MCl 2 {η 2 -2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 }-κP,κP] (7, M=Pd;10, M=Pt).Similarly the reaction of bisphosphite 2 with Pd(COD)MeCl affords cis-[PdMe(Cl)η 2 -2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 -κP,κP] (8).Treatment of 2 with [Pd(η 3 - C 3 H 5 )Cl] 2 in the presence of AgClO 4 furnish the cationic complex, [Pd(η 3 -C 3 H 5 )η 2 -2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 -κP,κP]ClO 4 (9). The binuclear complex, [Au 2 Cl 2 {2,6-C 5 H 3 N{CH 2 OP(–OC 10 H 6 )(μ-S)(C 10 H 6 O–)} 2 }-κP,κP] (11) is obtained in the reaction of compound 2 with two equiv. of AuCl(SMe 2 ), where the ligand exhibits bridged bidentate mode of coordination. All the complexes are characterized by the 1 H NMR, 31 P NMR, elemental analysis and mass spectroscopy data. The cationic ruthenium complex 5 is proved to be an active catalyst for the hydrogenation of styrene and α-methyl styrene.