Fluorophenyl -5-methyl-pyridine, F-mppy

To a 100-mL round-bottomed flask are added 2-bromo—4 -f uoroacetophenone (4.87 g, 22.4 mmol) and pyridine (50 mL). After stirring the mixture vigorously at room temperature for 1 h, the white pyridinium salt is collected by vacuum filtration and washed with diethyl ether (3 x 20 mL) (6.00 g, 20.3 mmol, 90% yield). In a 500-mL round-bottomed flask equipped with a reflux condenser, the pyridinium salt (5.00 g, 16.9 mmol) is dissolved in methanol (100 mL) before adding 2-methylacrolein (1.18 g, 16.8 mmol) and ammonium acetate (6.97g, 90.5 mmol). The mixture is heated at reflux for 18 h during which time the reaction turns dark red. The reaction mixture is cooled to room temperature and then poured into water (400 mL). The colorless product is isolated by vacuum filtration, washed with water (150 mL), and dried under reduced pressure. This procedure yields F-mppy as a white solid. Yield 1.69 g, 9.03 mmol (54%). TLC (silica, Sorbent 1624147, 10% ethyl acetate in hexanes, F-mppy 7 f=0.18) and NMR analyses indicate that further purification is not necessary. 

-CHLOROTETRAKIS[5-FLUORO-2-(5-METHYL-2-PYRIDINYL-1V)PHENYL-C]DIIRIDIUM(III), [Ir(F-mppy)2Cl]2 

Cleavage of [Ir(F-mppy)2Cl]2 by 2,2 -bipyridine gives [Ir(F-mppy)2(bpy)] 1. Relative to the ppy derivative, the fluorinated complex exhibits an increased emission energy, excited-state lifetime, and quantum yield of emission.9 

OXYGEN AND CARBON BOUND ACETYLACETONATO IRIDIUM(ffl) COMPLEXES 

Submitted by STEVEN M. BISCHOF and ROY A. PERIANA Checked by MARK R. RINGENBERG1 and THOMAS B. RAUCHFUSS1 

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