TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The electronic device comprises at least one matrix material used with (I) in at least one emitting layer, comprising a ketone, phosphine oxide, sulfoxide, sulfone, triarylamine, carbazole derivative, indolocarbazole derivative, indenocarbazole derivative, azacarbazole, bipolar matrix material, silane, azaborole, boronic ester, diazasilole derivative, diazaphosphole derivative, triazine derivative, zinc complex, dibenzofuran derivative or bridged carbazole derivative.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Claimed): The preparation of (I), comprises reacting a free ligand (L or L1) with metal alkoxide compounds of formula (M(OR)n) (III), metal ketoketonate compounds of formula (IV), metal halide compounds of formula (M(Hal)n) (V), dimeric metal complexes of formula (VI), metal complexes of formula ((((L1)m-M(L2)2)+)(Z1)) (VII) or metal compounds, preferably iridium compounds carrying alkoxide-, halide- and/or hydroxy- and ketoketonate groups.Hal = F, Cl, Br or I;L2 = alcohol or nitrile; andZ1 = non-coordinating anion. Preferred Definitions:    M = Cr, Mo, W, Re, Ru, Os, Rh, Ir, Ni, Pd, Pt, Cu, Ag or Au;    Ar1 = substituted pyridine-diyl moieties of formula (VIIIa), substituted isoquinoline-diyl moieties of formula (VIIIb), substituted quinoline-diyl moieties of formula (VIIIc), substituted quinoxaline-diyl moieties of formula (VIIId), substituted heterocyclyl moieties of formula (VIIIe) or (VIIIg), substituted isoquinoline-diyl moieties of formula (VIIIf) or substituted phenanthridine-diyl moieties of formula (VIIIh);    W1 = NR, O or S; and    L1 = CO, NO, alkyl cyanide, aryl cyanide, alkyl isocyanide, aryl isocyanide, NH2, phosphine, phosphite, arsine, stibine, nitrogen-containing heterocyclyl, carbene, hydride, deuteride, F-, Cl-, Br-, I-, alkyl acetylidene, aryl acetylidene, CN, cyanate, isocyanate, thiocyanate, isothiocyanate, aliphatic- or aromatic alkoxide, aliphatic- or aromatic thioalkoxide, amide, carboxylate, aryl, O2-, S2-, carbide, nitrene, diamine, imine, diimine, diphosphine, 1,3-diketonate derived from 1,3-diketone, 3-ketonate derived from 3-ketoester, carboxylate derived from amino-carboxylic acid, salicyliminate derived from salicylimine, dialkoxide, dithiolate, borate, nitrogen-containing heterocyclyl, bidentate, monoanionic and neutral or dianionic ligand which with the metal forms cyclometalated five- or six-membered ring having at least one metal-carbon bond, preferably cyclometalated five-membered ring, eta 5-cyclopentadienyl, eta 5-pentamethylcyclopentadienyl, eta 6-benzene or eta 7-cycloheptatrienyl.    SPECIFIC COMPOUNDS - Approximately 117 Compounds (I) are disclosed e.g. iridium complexes of formula (Ia)-(Ie).    EXAMPLE - Mixture of 10 mmol sodium(cis-, trans-di-chloro-(bis-acetylacetonato)iridate(III) and 60 mmol 2-(1H-indene-2-yl)pyridine in 50 ml propylene glycol was heated under a gentle stream of argon for 60 hours under gentle reflux. Then the mixture was cooled to 60 degrees C and then worked up to obtain (Ia).