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We present a pair of 15 cm × 15 cm all-phosphorescent OLED light panels with high efficacy and extended operational lifetime. Panel 1 operates at 1,000 cd/m2 with power efficacy = 62 lm/W. At a higher luminance of 3,000 cd/m2, power efficacy = 49 lm/W, CRI = 82, CCT = 2,950 K and CIE 1931 (x, y) = (0.446, 0.417). Similar high efficacy performance is recorded for Panel 2, which has lifetime to LT70 ∼ 4,000 hrs at 3,000 cd/m2. Excellent lifetime is enabled by a new light blue phosphorescent materials system and by the use of efficient phosphorescent emitters that ensure very low panel temperature without any additional thermal management.

The synthesis, spectral characteristics, and X-ray structures for dirhodium(II) tetrakis[methyl 2-oxooxazolidin-4(S)-carboxylate], Rh2(4S-MEOX)4, and the related dirhodium(II) tetrakis[methyl 5(R)-methyl-2-oxooxazolidin-4(S)-carboxylate], Rh2(4S-THREOX)4, are reported. Comparison is made between these 2-oxooxazolidin-ligated dirhodium(II) catalysts for metal carbene transformations and those with comparable 2-oxopyrrolidine ligands, especially dirhodium(II) tetrakis[methyl 2-oxopyrrolidine-5(S)-carboxylate], Rh2(5S-MEPY)4. Structure-selectivity comparisons reveal that Rh2(4S-MEOX)4 provides higher enantiocontrol and, in some cases, higher diastereocontrol than Rh2(5S-MEPY)4 in intramolecular carbon-hydrogen insertion reactions of sterically demanding diazoacetates and diazoacetamides and is the catalyst of choice for highly enantioselective diazodecomposition of adamantyl diazoacetates and N-(tert)butyldiazoacetamides. The structurally analogous Rh2(4S-THREOX)4 is nearly identical with Rh2(4S- MEOX)4 in its overall effect on selectivity. The net advantage of Rh2(4S-MEOX)4 lies in its wider openness for metal carbene transformations.

We present the results of a study using vibrational circular dichroism (VCD) for (+)-1, which furnished an unambiguous determination of its absolute configuration as S. The most abundant conformation of (+)-1 in CDCl3 solution was also established. Chirality 14:215–219, 2002. © 2002 Wiley-Liss, Inc.

The Rh¹¹‐catalyzed carbenoid addition of diazoacetates to olefins was investigated with [Rh₂{(4S)‐phox}₄] (1;phox = tetrakis[(4S)‐tetrahydro‐4‐phenyloxazol‐2‐one]), [Rh₂{(2S)‐mepy}₄] (2; mepy = tetrakis[methyl (2S)‐tetrahydro‐5‐oxopyrrole‐2‐carboxylate]), and [Rh₂(OAc)₄] (3). While catalysis with 2 and 3 afford preferentially trans‐cyclopropanecarboxylates, the cis‐isomers are the major products with 1. In general, the enantioselectivities achieved with 1 and 2 are comparable. Additions catalyzed by 1 are strongly sensitive to steric effects. Highly substituted olefins afford cyclopropanes in only poor yield. The preferential cis‐selectivity observed in reactions catalyzed by 1 is attributed to dominant interactions between the ligand of the catalyst and the substituents of both olefin and diazoacetate, which overrule the steric interactions between olefin and diazoacetate in the transition state for carbene transfer.

Diazodecomposition of 1,3-dialkoxy-2-propyl diazoacetates catalyzed by chiral dirhodium(II) carboxamides results in highly enantioselective and diastereoselective carbon-hydrogen insertion which forms 3,5-dialkyl 2-deoxyxylolactones in up to 98% enantiomeric excess.

The synthesis, spectral characteristics, and X-ray structures for dirhodium(II) tetrakis[methyl 2-oxooxazolidin-4(S)-carboxylate], Rh2(4S-MEOX)4, and the related dirhodium(II) tetrakis[methyl 5(R)-methyl-2-oxooxazolidin-4(S)-carboxylate], Rh2(4S-THREOX)4, are reported. Comparison is made between these 2-oxooxazolidin-ligated dirhodium(II) catalysts for metal carbene transformations and those with comparable 2-oxopyrrolidine ligands, especially dirhodium(II) tetrakis[methyl 2-oxopyrrolidine-5(S)-carboxylate], Rh2(5S-MEPY)4. Structure-selectivity comparisons reveal that Rh2(4S-MEOX)4 provides higher enantiocontrol and, in some cases, higher diastereocontrol than Rh2(5S-MEPY)4 in intramolecular carbon-hydrogen insertion reactions of sterically demanding diazoacetates and diazoacetamides and is the catalyst of choice for highly enantioselective diazodecomposition of adamantyl diazoacetates and N-(tert)butyldiazoacetamides. The structurally analogous Rh2(4S-THREOX)4 is nearly identical with Rh2(4S- MEOX)4 in its overall effect on selectivity. The net advantage of Rh2(4S-MEOX)4 lies in its wider openness for metal carbene transformations.

Summary Dirhodium(II) tetrakis[methyl 1-(3-phenylpropanoyl)imidazolidin-2-one-4(S)-carboxylate], Rh 2 (4S-MPPIM) 4 , provides significant enhancement in enantiocontrol for intramolecular cyclopropanation reactions of allylic diazoacetates and optimal enantiocontrol/diastereocontrol for intramolecular C-H insertion reactions of secondary alkyl diazoacetates.

A novel method for the efficient synthesis of 1,8-diazabicyclo[4.3.0]non-3-ene-7,9-diones 5 (bicyclic hydantoins) starting from ureas or Z-protected aminoacids has been developed. The key step is a ring-closing metathesis (RCM) reaction of diallyl substituted hydantoins 3 catalyzed by the ruthenium-carbene complex bis(tricyclohexylphosphine)benzilidine ruthenium dichloride ( 4 ).

1,3-Dioxan-5-yl diazoacetates are valuable substrates for highly diastereoselective and enantioselective carbon-hydrogen insertion reactions. trans-2-(tert-Butyl)-1,3-dioxan-5-yl diazoacetate is a direct precursor to 2-deoxyribono-1,4-lactone in up to 81% ee, whereas cis-2-(tert-butyl)-1,3-dioxan-5-yl diazoacetate yields only the protected 2-deoxyxylono-1,4-lactone in up to 96% ee. However, trans-2-aryl-1,3-dioxan-5-yl diazoacetate (aryl = phenyl or 2-naphthyl) forms the precursor to 2-deoxyxylono-1,4-lactone in up to 95% ee but with the mirror image configuration of that produced from the trans-2-(tert-butyl) analogue. The catalysts that are most suitable for these carbon-hydrogen insertion reactions are chiral dirhodium(II) carboxamidates. 1,3-Dialkoxy-2-propyl diazoacetates give mainly 2-deoxyxylono-1,4-lactone derivatives (>90:10) with generally high enantiocontrol, but replacement of hydrogen at the 2-position of these 2-propyl diazoacetates led to a mixture of products.

— In this paper, the design criteria for scaling up from small-area organic light-emitting-diode (OLED) pixels to large-area OLED light panels is described. Particular focus is placed on using phosphorescent OLEDs (PHOLEDs) to maximize panel efficacy and uniformity and minimize operating temperature. Data for a pair of all-phosphorescent 15 × 15 cm OLED light panels are also presented: Panel 1 has 62-lm/W efficacy, CRI = 81, CCT = 3180K, and lifetime to LT70 = 18,000 hours at 1000 cd/m2 and Panel 2 has 58-lm/W efficacy, CRI = 82, CCT = 2640K, and lifetime to LT70 = 30,000 hours at 1000 cd/m2. Operating at a 3000 cd/m2 (7740 lm/m2), Panel 2 has 49-lm/W efficacy with lifetime to LT70 = 4000 hours. Excellent panel lifetime is enabled by a stable light-blue phosphorescent materials system and by the use of efficient phosphorescent emitters that ensure very low panel temperature without any additional thermal management.