Preparation and characterization of rhodium(III), iridium(III) and ruthenium(II) bearing 1,3- or 1,4-dithianes

Reactions of [Cp*MCl2]2(1a: M = Rh, 1b: M = Ir) or [(arene)RuCl2]2(1c: arene =p-cymene; 1d: arene = C6Me6) with 1,3-dithiane (1,3S2C4H8) gave [{LMCl2}2(1,3-S2C4H8)]2 and [(LMCl2)( 1,3-S2C4H8)]3(LM = Cp*Rh, Cp*Ir, or (p-cymene)Ru, (C6Me6)Ru), depending on molar ratios between 1 and 1,3-dithiane. The reaction in the presence of KPF6 afforded the corresponding ionic complexes [LMCl(1,3S2C4H8)2](PF6)4. Complex 3a was treated with 1b, affording the heterobinuclear complex [Cp*RhCl2(1,3-S2C4H8)IrCl2Cp*]2ab. Complex 2ab was obtained by a similar reaction of 3b with 1a, whereas reactions of 1c with 3a or 3b gave homonuclear complexes 2c and 2a(or 2b). Ionic complexes 4 were treated with 1, generating homo- or hetero-trinuclear complexes [{LMCl(1,3-S2C4H8)2}(LʹMCl2) 2](PF6)5(LM = Cp*Ir, L M = Cp*Rh, Cp*Ir, or (p-cymene)Ru: LM = Cp*Rh, LʹM =(p-cymene)Ru). Reactions of 1 with 1,4-dithiane (1,4S2C4H8) were carried out in a 1 : 1 molar ratio, generating binuclear complexes [(Cp*MCl2)2(1,4-S2C4H8)](6a: M = Rh; 6b: M = Ir) or [{(arene)RuCl2}2(1,4-S2C4H8)](arene =p-cymene (6c), C6Me6(6d)). Reaction of 1a with an excess of 1,4-dithiane afforded a neutral mononuclear complex [Cp*RhCl2(1,4-S2C4H8)]7a, whereas the reactions of 1b or 1c generated the corresponding ionic complexes [Cp*IrCl(1,4-S2C4H8)](Cl)8b and [(p-cymene)RuCl(1,4-S2C4H8)](Cl)8c. Treatment in the presence of KPF6 gave ionic complexes [LM (1,4-S2C4H8)](PF6)(LM = Cp*Rh (9a), Cp*Ir (9b), (p-cymene)Ru (9c)) Structures of 2a, 2ab, 3a, 3c, 4a, 8b and 9c were confirmed by Xray analyses.