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The development of a one-step borylation of 1,3-diaryloxybenzenes, yielding novel boron-containing polycyclic aromatic compounds, is reported. The resulting boron-containing compounds possess high singlet-triplet excitation energies as a result of localized frontier molecular orbitals induced by boron and oxygen. Using these compounds as a host material, we successfully prepared phosphorescent organic light-emitting diodes exhibiting high efficiency and adequate lifetimes. Moreover, using the present one-step borylation, we succeeded in the synthesis of an efficient, thermally activated delayed fluorescence emitter and boron-fused benzo[6]helicene. [ABSTRACT FROM AUTHOR]

Reports on the preparation of a series of aqua-Cr(III)- dioxolene complexes. Linkage of dioxolene in the complexes to CR(III) with the semiquinone form; Change of all aqua- Cr(III) complexes to the hydroxo-Cr(III) ones upon dissociation of the aqua proton.

Presents the findings of an experiment on the synthesis, structures and properties of bis(micro-oxo)nickel(III) and bis(micro-superoxo)nickel(II) complexes resulting from the oxygenation of the two compounds' ligands. Formation of nickel compounds during the decomposition process; Reaction of samples with hydrogen peroxide.

The triplet-energy control of polycyclic aromatic hydrocarbons (PAHs) was achieved by heteroatom incorporation. For instance, 4b-aza-12b-boradibenzo[g,p]chrysene showed a much larger ET value than the corresponding PAH, dibenzo[g,p]chrysene, and enable us to built phosphorescent organic light-emitting diodes (PHOLEDs) of high performance. We have also synthesized a variety of heteroatom-incorporated polycyclic aromatics with a large ET value, which improved not only efficiency of PHOLED but also lifetime. [ABSTRACT FROM AUTHOR]

A series of heterodinuclear bis(mu-hydroxo)chromium(III)nickel(II) complexes was newly prepared: [(phen)(2)Cr(mu-OH)(2)Ni(tpa)](ClO(4))(3) x 0.5H(2)O (1), [(phen)(2)Cr(mu-OH)(2)Ni(Me-tpa)](ClO(4))(3) x 2H(2)O (2), [(phen)(2)Cr(mu-OH)(2)Ni(Me(2)-tpa)](ClO(4))(3) x 2H(2)O (3), and [(phen)(2)Cr(mu-OH)(2)Ni(Me(3)-tpa)](ClO(4))(3) x 3H(2)O (4), where phen is 1,10-phenanthroline and tpa, Me-tpa, Me(2)-tpa, and Me(3)-tpa are tris(2-pyridylmethyl)amine, [(6-methyl-2-pyridyl)methyl]bis(2-pyridylmethyl)amine, bis[(6-methyl-2-pyridyl)methyl](2-pyridylmethyl)amine, and tris[(6-methyl-2-pyridyl)methyl]amine, respectively. X-ray crystallography revealed that the structures of 1-4 resemble one another having an edge-shared bioctahedral structure with a Cr(mu -OH)(2)Ni unit (crystal data: 1 x C(2)H(5)OH, triclinic, P1, a = 13.179(4) A, b = 13.685(4) A, c = 14.260(4) A, alpha = 84.95(2) degrees, beta = 77.65(1) degrees, gamma = 90.21(2) degrees, V = 2502(1) A(3), Z = 2, R = 0.103, R(w) = 0.097; 2 x C(2)H(5)OH, triclinic, P1, a = 13.214(2) A, b = 13.657(2) A, c = 14.417(3) A, alpha = 95.205(5) degrees, beta = 102.583(4) degrees, gamma =90.720(3) degrees, V = 2527.3(8) A(3), Z = 2, R = 0.090, R(w) = 0.122; 3 x C(2)H(5)OH, triclinic, P1, a = 13.276(2) A, b =13.696(2) A, c = 14.454(2) A, alpha = 95.640(3) degrees, beta = 102.821(4) degrees, gamma = 90.174(3) degrees, V = 2549.5(6) A(3), Z = 2, R= 0.087, R(w)= 0.119; 4, triclinic, P1, a = 10.8916(9) A, b = 14.268(2) A, c = 17.522(2) A, alpha = 84.498(9) degrees, beta = 74.313(7) degrees, gamma = 72.402(7) degrees, V = 2498.6(5) A(3), Z = 2, R = 0.060, R(w)= 0.088). Chromium and nickel ions are coordinated by two phen's and Me(n)-tpa, respectively, to complete a distorted octahedral coordination sphere. Introduction of the 6-methyl group(s) onto the pyridyl group(s) results in the elongation of the Ni-N bond distances due to an unfavorable steric interaction between the methyl group and the bridging hydroxide group: systematic elongation of the Ni-N bond distances and the Cr ...Ni separations accompanied by an increase in the Cr-O-Ni angles was observed as the number of the methyl groups increases. Variable-temperature magnetic susceptibility measurements of 1-4 (4.2-300 K) indicated that magnetic interactions between Cr(III) and Ni(II) ions are systematically modulated from a very weak antiferromagnetic interaction to a ferromagnetic interaction as the number of the methyl groups increases; the exchange integrals J's for 1-4 are estimated to be -1.4, +0.0, +4.1, and +7.4 cm(-1), respectively. The magneto-structural relationship is discussed in terms of the change in the magnetic orbital energies of nickel(II) centers arising from the change in the Ni-N bond distances.