Trinuclear structures tridentate ligands

Using tridentate ligands with various functionalities and coordinating abilities, a series of neutral and cationic tri-, tetra- and hexanuclear metalla-cycles have been synthesised [34]. Cyclic tetramers composed of Cp Ir, Cp Rh or (arene)Ru half-sandwich complexes and 6-purinethione derivatives have been isolated as triflate salts [351. The cationic complex (Cp Ir)4(Ll)4 (where L1 = 2-amino-6-purinethione), presented in Fig. 9a, forms in the solid state an infinite channel-like structure with, S symmetry. Replacing the 6-purinethione with pyridine-4-thiolato bridging ligands (L2), the trinuclear metalla-cycle [(Cp Ir)3(L2)3] was obtained (Fig. 9b) [36]. 

P-8a Tridentate phosphine ligands yield trinuclear complexes with Au(I) halides of structure... 

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