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New soluble host materials with benzocarbazole and triphenyltriazine moieties, 11-[3-(4,6-diphenyl-[1,3,5]triazin-2-yl)-phenyl]-11H-benzo[a]carbazole and 11-[3′-(4,6-diphenyl-[1,3,5]triazin-2-yl)-biphenyl-4-yl]-11H-benzo[a]carbazole, were synthesized for highly efficient red phosphorescent organic light-emitting diodes (PHOLED). Hole-transporting benzocarbazole moiety and electron transporting triphenyltriazine moiety, which are severely twisted each other enhance the solubility of those materials in common organic solvent. The improved solubility from this molecular design could be due to a reduced π–π stacking interaction, which gives a very uniform film morphology after spin coating of those materials. As a result, we obtained highly efficient soluble PHOLEDs combined with an evaporated blue common layer structure. The resultant red PHOLED exhibited the maximum current efficiency as well as external quantum efficiency values up to 23.7 cd/A and 19.0%.

The hydrogenolysis of polymer-bound arenesulfonates by 2-propylmagnesium chloride was performed through reductive cleavage of the C-S bond in the presence of a nickel catalyst. The reaction underwent in the highest efficiency by adding 15 equiv of the nucleophile in two additions with in THF. Various unfunctionalized naphthalene, biphenyl, and stilbene derivatives were produced in good yields by the traceless sulfonate linker system at room temperature.

), have been adopted as elect rophilic substrates in these reactions. Diverse organometallic nucleophiles, such as organo-boronic acids, organostannanes, organozincs and organomag-nesiums, have also been successfully applied as nucleophilic substrates.While many transition metal catalysts have been examined to promote the C-C couplings, nickel- and palladium complexes have occupied a predominant place as the versatile catalysts. The activity of the transition-metal catalysts strongly depends on the combination of ligand and metal.

Unfunctionalized biaryl compounds were parallelly and combinatorially prepared by the traceless hydrogenolysis of biarylsulfonates supported on pentaerythritol. The hydrogenolysis using 2-propylmagnesium chloride in the presence of dppfNiCl2 efficiently generated corresponding biaryl derivatives without any memory of the support. The strategy using pentaerythritol as a small soluble support was disclosed to have a potential to combine the benefits of both SPOS and solution-phase reaction with fast reaction rate, facile isolation of intermediates, easy analysis of intermediates and atom economical manner. The novel tetrapodal support is expected to be an efficient substitute for polymeric supports in many circumstances.

Quantum mechanical properties of unsymmetrical and unfunctionalized trans-stilbene derivatives 1-3, which had been prepared by solid-phase parallel syntheses, were characterized using mPW1PW91/6-311G(d,p) (hybrid HF-DF) calculations. The total electronic energies, normal vibrational modes, Gibbs free energies, and HOMOs and LUMOs of sixteen different structures from three different groups were analyzed. The energy differences between the HOMOs and LUMOs of the various unsymmetrical trans-stilbenes are in accord with the maximum absorption peaks of the experimental UV spectra of 1-3. The calculated normal vibrational modes of 2l were comparable with its experimental IR spectrum. The π-conjugation in the para-connected biphenyl group of 2 is better than the one in the metaconnected biphenyl group on the shorter side of 3.

A small library of fluorescent and unsymmetrical trans-stilbene compounds was efficiently produced by a solid-phase synthetic approach using the sulfonate-based traceless linker system. Nickel(0)-catalyzed cleavage/cross-coupling of polymer-bound stilbenesulfonates with aryl Grignard reagents generated the desired trans-stilbenes at high yield by the multifunctional release facilitating the additional diversification of the library. The luminescent properties of trans-stilbenes are assessed, and the influence of alkyl substituents on their photophysical properties is discussed.

Nickel N-heterocyclic carbene (NHC) catalytic system prepared in situ by the reaction of Ni(acac)(2) with NHC precursor efficiently catalyzed the cross-coupling reaction of alkoxysulfonylarenes with methyl, neopentyl, and benzyl Grignard reagents at ambient temperature.

Application of a novel sulfonate-based traceless multifunctional linker system using pentaerythritol as a tetrapodal soluble support was demonstrated using liquid-phase parallel and combinatorial preparation of biphenyl and terphenyl compounds. Nickel-catalyzed reactions of pentaerythritol tetrakis(arenesulfonate)s with arylmagnesium bromides generated the desired products in sufficient yields through reductive cleavage/cross-coupling of the C-S bond. Homogeneous pentaerythritol-supported reactions could be accomplished using less nucleophile with shorter reaction periods than could the corresponding heterogeneous polymer-supported reactions. This liquid-phase approach using a small polyfunctionalized support combines advantages of solution-phase and solid-phase syntheses by allowing high reactivity, high atom economy, simple isolation, and real-time monitoring of the reaction progress.

Palladium-catalyzed cross-coupling reactions of neopentyloxysulfonylphenyl bromides with arylboronic acids provided a variety of neopentyl biphenylsulfonates in good yields. 2-Bromo- and 4-bromobenzenesulfonates underwent the coupling reaction more rapidly than 3-bromobenzenesulfonate, while chlorobenzenesulfonate did not produce the coupling product under the standard reaction conditions.

The development of monomers that show no shrinkage in volume upon polymerization is highly desirable in the field of materials such as dental fillings, high-strength composites, precision castings, and adhesives. 1 Volume shrinkage during polymerization results from the conversion of van der Waals distances between monomers to covalent bond lengths. Since the van der Waals distance separates monomer molecules approximately three times greater than a covalent bond does, the formation of new covalent bonds upon polymerization is destined to produce the substantial amount of volume contraction. A hopeful approach to prevent this shrinkage could be attained by using monomers that polymerize via the double ring-opening process, which results in two bonds breaking for each new bond formation. Since the double ring-opening polymerization was reported in 1972, 2 various monomers based on spiro orthoester (SOE), 3 bicyclo orthoester (BOE), 4 polycyclic ketal lactone (PKL), 5 cyclic ether, 6 spiroketal, 7 and spiro orthocarbonate (SOC) skeletons 8 have been developed to show the expansion in volume upon polymerization. Among them, spiro orthocarbonates (SOCs) are the most widely investigated monomers because they show the biggest volume expansion. Moreover SOCs containing exo-methylene groups undergo the ring-opening polymerization not only with cationic initiators 9 but also with radical initiators. 10 Asymmetric SOCs possessing one exo-methylene group are more favorable than symmetric SOCs, because the extra exomethylene group remained in the polymer from symmetric monomers affords the crosslinking reaction that causes the volume shrinkage. 11 Recently, N,S- 12 and S,S-analogs 13 of

), have been adopted as elect rophilic substrates in these reactions. Diverse organometallic nucleophiles, such as organo-boronic acids, organostannanes, organozincs and organomag-nesiums, have also been successfully applied as nucleophilic substrates.While many transition metal catalysts have been examined to promote the C-C couplings, nickel- and palladium complexes have occupied a predominant place as the versatile catalysts. The activity of the transition-metal catalysts strongly depends on the combination of ligand and metal.

Pentaerythritol turns out to be an efficient soluble tetrapodal support permitting the traceless release of various biaryl compounds attached by a sulfonate linkage.

was obtained as a 60 : 40 mixture of geometric isomers that were not separable by common chromatographic methods. Fortunately, we observed that a careful recrystallizing process in 2-propanol facilitated the selective isolation of both isomers. Nuclear magnetic reso-nance (NMR) study showed that the initially recrystallized major product was (

Application of a novel sulfonate-based traceless multifunctional linker system using pentaerythritol as a tetrapodal soluble support was demonstrated using liquid-phase parallel and combinatorial preparation of biphenyl and terphenyl compounds. Nickel-catalyzed reactions of pentaerythritol tetrakis(arenesulfonate)s with arylmagnesium bromides generated the desired products in sufficient yields through reductive cleavage/cross-coupling of the C–S bond. Homogeneous pentaerythritol-supported reactions could be accomplished using less nucleophile with shorter reaction periods than could the corresponding heterogeneous polymer-supported reactions. This liquid-phase approach using a small polyfunctionalized support combines advantages of solution-phase and solid-phase syntheses by allowing high reactivity, high atom economy, simple isolation, and real-time monitoring of the reaction progress.

Neopentyl arenesulfonates react with secondary alkylmagnesium chlorides in the presence of dppfNiCl2 to produce the corresponding arenes via the reductive cleavage of carbon-sulfur bond. Highest yield is obtained by using three equivalents of Grignard reagent to a mixture of arenesulfonate and dppfNiCl2 in Et2O at room temperature. This reaction represents a novel method allowing the efficient hydrogenolysis of sulfur-containing groups in aromatic compounds.