Iridium(III) and rhodium(III) cyclometalated complexes containing sulfur and selenium donor ligands

Treatment of [M(Buppy)(2)Cl](2) (M = Ir (1), Rh (2); BuppyH = 2-(4'-tert-butylphenyl)pyridine) with Na(Et2NCS2), K[S2P(OMe)(2)], and K[N(Ph2PS)(2)](2) afforded monomeric [Ir(Buppy)(2)((SS)-S-boolean AND)] (SAS=Et2NCS2 (3), S2P(OMe)(2) (4), N(PPh2S)(2) (5)) and [Rh(Buppy)(2)((SS)-S-boolean AND)] ((SS)-S-boolean AND=Et2NCS2 (6), S2P(OMe)(2) (7), N(PPh2S)(2) (8)), respectively. Reaction of 1 with Na[N(PPh2Se)(2)] gave [Ir(Buppy)(2){N(PPh2Se)(2)}] (9). The crystal structures of 3, 4, 7, and 8 have been determined. Treatment of 1 or 2 with AgOTf (OTf = triflate) followed by reaction with KSCN gave dinuclear [{M(Buppy)(2)}(2)(mu-SCN)(2)] (M =Ir (10), Rh (11)), in which the SCN- ligands bind to the two metal centers in a mu-S,N fashion. Interaction of 1 and 2 with [Et4N](2)[WQ(4)] gave trinuclear heterometallic complexes [{Ir(Buppy)(2)}(2)(mu-WQ(4))] (Q = S (12), Se (13)) and [{Rh(Buppy)(2)}(2){(mu-WQ)(4)}] (Q = S (14), Se (15)), respectively. Hydrolysis of 12 led to formation of [{Ir(Buppy)(2)}2{W(O)(muS)(2)(mu(3)-S)}] (16) that has been characterized by X-ray diffraction. (C) 2004 Elsevier B.V. All rights reserved.