Ruthenium chalcogenonitrosyl and bridged nitrido complexes containing chelating sulfur and oxygen ligands

Abstract

Ruthenium thio- and seleno-nitrosyl complexes containing chelating sulfur and oxygen ligands have been synthesised and their de-chalcogenation reactions have been studied. The reaction of mer-[Ru(N)Cl₃(AsPh₃)₂] with elemental sulfur and selenium in tetrahydrofuran at reflux afforded the chalcogenonitrosyl complexes mer-[Ru(NX)Cl₃(AsPh₃)₂] [X = S (1), Se (2)]. Treatment of 1 with KN(R₂PS)₂ afforded trans-[Ru(NS)Cl{N(R₂PS)₂}₂] [R = Ph (3), Prⁱ (4), Bu^t (5)]. Alternatively, the thionitrosyl complex 5 was obtained from [Buⁿ₄N][Ru(N)Cl₄] and KN(Bu^t₂PS)₂, presumably via sulfur atom transfer from [N(Bu^t₂PS)₂]⁻ to the nitride. Reactions of 1 and 2 with NaL_OEt (L_OEt⁻ = [Co(η⁵-C₅H₅){P(O)(L_OEt)₂}₃]⁻) gave [Ru(NX)L_OEtCl₂] (X = S (8), Se (9)). Treatment of [Buⁿ₄N][Ru(N)Cl₄] with KN(R₂PS)₂ produced Ru^IV–Ru^IV μ-nitrido complexes [Ru₂(μ-N){N(R₂PS)₂}₄Cl] [R = Ph (6), Prⁱ (7)]. Reactions of 3 and 9 with PPh₃ afforded 6 and [Ru(NPPh₃)L_OEtCl₂], respectively. The desulfurisation of 5 with [Ni(cod)₂] (cod = 1,5-cyclooctadiene) gave the mixed valance Ru^III–Ru^IV μ-nitrido complex [Ru₂(μ-N){N(Bu^t₂PS)₂}₄] (10) that was oxidised by [Cp₂Fe](PF₆) to give the Ru^IV–Ru^IV complex [Ru₂(μ-N){N(Bu^t₂PS)₂}₄](PF₆) ([10]PF₆). The crystal structures of 1, 2, 3, 7, 9 and 10 have been determined.