TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: The photoactive layer comprises (I) and further comprises a host material.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): Preparation of (I) comprises: reacting optionally substituted N-benzoylpyridinium ylide with optionally substituted (E)-(2-iodovinyl)benzene to form phenyl-pyrazolopyridine ligand (L); reacting iridium(III) chloride hydrate with excess (L) in heated mixture of 2-ethoxyethanol and water to form phenyl-pyrazolopyridine iridium chloride dimer (a); reacting (a) with silver triflate to form phenyl-pyrazolopyridine iridium triflate (b); and reacting (b) with excess (L) in refluxing 2-ethoxyethanol to afford cyclometallated (I). Preferred Definitions:    R1, R3 = 1-10C alkyl, 6-20C aryl or their deuterated analogs;    R2, R4 = 1-10C alkyl, 6-20C aryl, electron-withdrawing group or their deuterated analogs; or    at least one of R2 and R4 = electron-withdrawing group, which is F or perfluoroalkyl; and    at least one of R6-R9 = 1-10C alkyl or deuterated alkyl; or    one of R8 and R9 = 6-20C aryl or deuterated aryl; or    R6-R9 = H or D.    SPECIFIC COMPOUNDS - 8 Compounds (I) are specifically claimed e.g. tris(2-(2,4-difluorophenyl)pyrazolo(1,5-a)pyridine) iridium of formula (Ia), tris(2-(2,4-difluoro-phenyl)-5-methyl-pyrazolo(1,5-a)pyridine) iridium, tris(5,6-dimethyl-2-(6-trifluoromethyl-biphenyl-3-yl)-pyrazolo(1,5-a)pyridine) iridium, tris(2-(4-ethyl-2-fluoro-phenyl)-5-isopropyl-pyrazolo(1,5-a)pyridine) iridium and 5-(tert-butyl-dimethyl-silanyl)-2-(3-fluoro-biphenyl-4-yl)-pyrazolo(1,5-a)pyridine.    EXAMPLE - 5.17 g Of N-benozylpyridinium ylide and 3.47 g of (E)-2,4-difluoro-1-(2-iodovinyl)benzene were mixed in 50 ml of dioxane in a pressure bottle, in a dry box. Then 0.69 g of the solution of tris(4-methoxyphenyl)phosphine and 0.173 g of palladium bromide in 10 ml of dioxane was added to the mixture, followed by the 8.95 g of silver benzoate. The mixture was stirred at 120 degrees C for 16 hours outside dry box. After cooling the mixture, methylene chloride was added to the mixture, then the obtained mixture was filtered through silica bed. Saturated ammonium bicarbonate solution was added to the filtrate, the separated organic layer was dried over anhydrous magnesium sulfate and chromatographed to give 2-(2,4-difluorophenyl)pyrazolo(1,5-a)pyridine (A1). 1.27 g Of (A1) and 0.927 g of iridium(III) chloride trihydrate were mixed together in 10 ml of 2-ethoxyethanol/3 ml of water solvent. The obtained mixture was stirred at 110 degrees C overnight under nitrogen. After cooling the mixture, water was added to the reaction mixture to result in solid precipitation. The precipitate was filtered and washed with methanol to give bis(2-(2,4-difluorophenyl)pyrazolo(1,5-a)pyridine) iridium chloride (A2). The reaction mixture of 1.3 g of (A2) and 0.486 g of silver triflate in 24ml of dichloromethane/1.3 ml of methanol was refluxed for 24 hours. After cooling the mixture, it was filtered through a column. The filtrate was concentrated under reduced pressure to give bis(2-(2,4-difluorophenyl)pyrazolo(1,5-a)pyridine) iridium triflate (A3). The mixture of 1.2 g of (A3) and 0.69 g of (A1) in 25 ml of 2-ethoxyethanol was stirred at 120 degrees C under nitrogen for 3 days. After cooling the mixture, water was added to the mixture. The precipitated solid was filtered and purified to give 0.3 g, 23% of tris(2-(2,4-difluorophenyl)pyrazolo(1,5-a)pyridine) iridium.