RESUMEN
We report the diastereo- and enantioselective conjugate addition of chiral secondary borylalkyl copper species derived from borylalkenes inâ situ to α,ß-unsaturated diesters. In the presence of a chiral bisphosphine-ligated CuH catalyst, the conjugate addition provides a direct access to enantioenriched alkylboron compounds containing two contiguous carbon stereogenic centers in good yield with high diastereo- and enantioselectivity (up to >98:2 dr, >99:1 er) by assembling readily available starting alkenyl reagents in a single operation without using preformed organometallic reagents or chiral auxiliaries. The resulting products were used in various organic transformations. The utility of the synthetic approach was highlighted by the synthesis of (-)-phaseolinic acid.
RESUMEN
Here, red phosphorescent platinum(II) complexes based on tetradentate pyridine-containing lig-ands are studied. To investigate their electroluminescent properties, multilayer devices were fabricated in the following sequence; ITO (180 nm)/4,4',4â³-Tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA) (30 nm)/N, N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl)4,4'-diamine (NPB) (20 nm)/ Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) (10 nm)/4,4'-Bis(N-carbazolyl)-1,1'-biphenyl (CBP) (20 nm)/Platinum(II) complex (20 nm)/1,3,5-Tris(1-Phenyl-1H-benzimidazol-2-yl)benzene) (TPBi) (40 nm)/Liq (2 nm)/Al (100 nm). In particularly, a device using platinum(II) complex based on N-(3,5-di-tert-butylphenyl)-3-(pyridin-2-yl)-N-(3-(pyridin-2-yl)phenyl)benzenamineligand showed the efficient red emission, with a luminous efficiency, power efficiency, and external quantum efficiency of, and the Commission International de LEclairge (CIE) coordinates of 27.26 cd/A, 10.54 lm/W, 8.50% at 20 mA/cm², and (0.65, 0.33) at 11.0 V, respectively.
RESUMEN
In this study, we designed and synthesized two phosphorescent emitting materials based on tetradentate pyridine-containing ligands. Their photophysical properties were examined for OLEDs and multilayer devices using these materials were fabricated in the following sequence; ITO (180 nm)/4,4',4â³-Tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA) (30 nm)/N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl)4,4'-diamine (NPB) (20 nm)/Tris(4-carbazoyl-9-ylphenyl)amine (TCTA) (10 nm)/4,4'-Bis(N-carbazolyl)-1,1'-biphenyl(CBP): 5, 8, 15% Platinum (II) complexes (20 nm)/1,3,5-Tris(1-Phenyl-1H-benzimidazol-2-yl)benzene) (TPBi) (40 nm)/Liq (2 nm)/Al (100 nm). In particularly, a device using Platinum (II) complex based on A/-(3,5-di-tert-butylphenyl)-6-phenyl-N-(6-phenylpyridin-2-yl)pyridin-2-amine ligand showed the efficient emission, with luminous efficiency, power efficiency, and external quantum efficiency, and the Commission International de LEclairge (CIE) coordinates of 29.29 cd/A, 9.37 lm/W, 8.66% at 20 mA/cm2, and (0.32, 0.62) at 8.0 V, respectively.
RESUMEN
To develop the efficient emitters for organic light-emitting diode (OLED), three indeno-type polyaromatic hydrocarbons materials were designed and synthesized through Buchwald-Hartwig amination. OLED devices using these materials were fabricated in the following sequence: indium-tin-oxide (ITO) (180 nm)/N,N'-diphenyl-N,N'-(2-napthyl)-(1,1'-phenyl)-4,4'-diamine (NPB) (50 nm)/Emitting materials (1-3) (30 nm)/4,7-diphenyl-1,10-phenanthroline (BPhen) (30 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm). All devices showed the efficient emissions. In particular, a device using 8,8-dimethyl-N,N-diphenyl-8H-indeno[2,1-b]fluoranthen-6-amine (2) as efficient emitter showed luminous efficiency, power efficiency, and external quantum efficiency of 8.35 cd/A, 5.70 lm/W, 2.37% at 20 mA/cm², respectively, with Commission Internationale d'Énclairage (CIE) coordinates of (0.37, 0.59) at 6.0 V.
RESUMEN
Two fluorescent benzo[g]quinoline derivatives were synthesized via Friedländer synthesis. Multilayered OLEDs using benzo[g]quinoline derivatives as the emitters showed unexpected emissions by electroplexes. Particularly, a device using 2-(naphthalen-3-yl)-4-phenylbenzo[g]quinoline as an emitting material exhibited efficient emission with a luminous efficiency, a power efficiency, an external quantum efficiency, and CIE coordinates of 3.58 cd/A, 1.11 lm/W, 1.08% at 20 mA/cm², and (0.36, 0.56) at 1,000 cd/m², respectively.