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Cationic cyclometalated iridium(III) complexes [(N,C-2'-2-phenylpyridyl)(2)Ir((NN)-N-boolean AND)](PF6) with alkyl-substituted 1-(2'-pyridyl)-pyrazole (NN)-N-boolean AND ligands exhibit green phosphorescence from a cyclometalating-ligand-centered excited state with structured emission spectrum and with quantum yield and excited-state lifetime of up to 26% and 1.4 mu s in argon-saturated dichloromethane solution. The alkyl groups do not change the energy or the nature of the emissive state; however, those alkyl groups that hinder coordination of the (NN)-N-boolean AND ligand to iridium(III) strongly quench phosphorescence of the complex. (C) 2013 Elsevier B.V. All rights reserved.

Cationic bis-cyclometalated iridium(III) complexes [(C boolean AND N)(2)Ir(N boolean AND N)](PF6) with 2-(2'-pyridyl)-5-R-1,3,4-oxadiazoles (N boolean AND N; R = 1-adamantyl, mesityl, N-diphenylamino) have a redox gap of 2.58-2.68 V and exhibit orange-red phosphorescence in argon-saturated dichloromethane solution with a maximum, quantum yield, and excited-state lifetime of 613-644 nm, 2-6%, and 90-280 ns. (C) 2012 Elsevier B. V. All rights reserved.

Two new cationic iridium(III) complexes with cyclometalating 1-phenylindazole or 2-phenyl-1,2,3-triazole ligands, [(C boolean AND N)(2)Ir(4,4'-di-tert-butyl-2,2'-dipyridyl)](PF6), exhibit yellow or green phosphorescence with quantum yields and excited state lifetimes of up to 45% and 840 ns in argon-saturated dichloromethane solution at room temperature. (C) 2012 Elsevier B. V. All rights reserved.

Bis-cyclometalated cationic Ir(III) diimine complexes [Ir((CN)-N-Lambda)2((NN)-N-Lambda)](PF6) with 1-phenylpyrazoles ((CN)-N-Lambda) and 1-(4'-tert-butyl-2'-pyridyl) pyrazole ((NN)-N-Lambda) are white solids that have absorption onset below 425 nm and electrochemical gap of up to 3.5 V. (C) 2011 Elsevier B. V. All rights reserved.

The planar aromatic imidazo[4,5-f]-1,10-phenanthroline ligands have been used to prepare platinum(II) chloride and thiolate complexes. The X-ray structures of two thiolate compounds are reported, which show column-like packing in the solid state due to intermolecular aromatic π–π interactions. The compounds absorb moderately in the visible region, owing to {charge-transfer-to-diimine} electronic transition.

A series of potentially dinucleating ligands, each with two bidentate imino–pyridine compartments, has been used to prepare the mononuclear complexes [Re(CO)3Cl(Ln)] (n=1–4) which each have a vacant binding site and so constitute ‘complex ligands’ for the stepwise synthesis of heterodinuclear complexes. Three of the complexes (with L1, L2 and L4) have been structurally characterised. The mononuclear complex [Re(CO)3Cl(L5)], arising from decomposition of [Re(CO)3Cl(L3)] by hydrolysis of the non-coordinated imine unit, was also isolated and structurally characterised. Luminescence studies show that these compounds are only very weak emitters. The ‘complex ligand’ [Re(CO)3Cl(L1)] has been reacted with [Ln(hfac)3]·2H2O (Ln=Yb, Er) to prepare the heterodinuclear complexes [Re(CO)3Cl(μ-L1)Ln(hfac)3] in which the {Ln(hfac)}3 unit is attached to the second bidentate imino–pyridine site of [Re(CO)3Cl(L1)]. The crystal structures of these show that the bridging ligand has to twist to accommodate the two bulky metal fragments, and that the lanthanide units have an 8-coordinate square-antiprismatic geometry.