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911.
[structure: see text] Single enantiomer, chiral donor-acceptor metal complexes were synthesized via the self-discriminating zinc(II) complexation of a pseudoracemic mixture of donor/acceptor-substituted bisoxazoline derivatives. 相似文献
912.
Stereoselective synthesis of 2'-C-methyl-cyclopropyl-fused carbanucleosides was accomplished via stereoselective cyclopropanation, regioselective cleavage of the isopropylidene group, stereoselective Grignard reaction, and cyclic sulfate chemistry. [reaction: see text] 相似文献
913.
[reaction: see text] A study on the gold (I)-catalyzed intramolecular hydroamination of trichloroacetimidates derived from propargyl and homopropargyl alcohols is described. In the presence of 2-5 mol % of cationic Au(I) complex, a variety of trichloroacetimidates undergo efficient hydroamination under an exceptionally mild condition. An orthogonality of the current catalytic protocol with those using a stoichiometric electrophile as well as a preliminary synthetic application as a stable precursor of 2-acylamino-1,3-diene has been demonstrated. 相似文献
914.
SeungHyun Shin 《Discrete Mathematics》2018,341(4):1125-1130
Izo() is the pseudogeometric graph for pG which satisfies the Krein equality and of which the local graph also satisfies the Krein equality. We prove that Izo() exists if and only if a spherical tight 4-design on exists. Nonexistence of infinitely many spherical tight 4-designs is well known. It gives the nonexistence of Izo() for infinitely many . Especially, Izo(4) does not exist, which was the first open case. 相似文献
915.
H. Kwak G. H. Eom S. H. Lee H. G. Koo S. P. Jang J. Lee W. Shin M. S. Lah C. Kim S.-J. Kim Y. Kim 《Journal of Structural Chemistry》2010,51(5):923-930
Five new Ni(II) complexes with pyridine carboxamide ligands have been synthesized and the crystal structures of three of the complexes were determined. Strong distortion effects of 6-methyl substitution were observed in the complexes with 6-methyl-substituted pyridyl bpb ligands. The C-H...F and C-H...O hydrogen bond interactions build extended architectures in the crystals studied. This result suggests that the steric effect of 6-methyl substitution plays an important role in the distortion of the structure, and the 6-methyl substitution can facilitate hydrogen bond interactions between methyl hydrogen atoms and O(carbonyl) or F atoms. Twelve Ni(II) complexes, including seven complexes reported previously, show reversible redox behavior, implying that the reduced Ni(I) state of each complex is stable in the time scale of CV measurement. The steric effect of R1 substituent and the electronic effects of X1 and X2 groups were found to be the main factors contributing to the shift of the redox potential of the Ni(II) complexes 相似文献
916.
Choi KM Lee SJ Choi JH Park TJ Park JW Shin WH Kang JK 《Chemical communications (Cambridge, England)》2010,46(45):8609-8611
A facile route to fabricate a protein-immobilized network pattern circuit for rapid and highly sensitive diagnosis was developed via the evaporation directed impromptu patterning method and selective avian influenza virus (AIV) immobilization. The response to the 10 fg mL(-1) anti-AI antibody demonstrates that this easy and simple circuit has about 1000 times higher sensitivity compared to those of conventional approaches. 相似文献
917.
918.
9,10-bis(3′′,5′′-diphenylbiphenyl-4′-yl)anthracene (TAT) and 4-(1′-(3′,5′-diphenylbiphenyl-4-yl)anthracen-9-yl)-N,N-diphenylaniline (TATa) which have electroluminescence (EL) maximum values of 441nm and 469 nm were used blue emitting materials in organic light emitting diodes (OLED). OLED devices were fabricated and characterized by co-deposited emitters of TAT and TATa with different ratios. C.I.E. values of the devices using TAT and TATa were changed from (0.148, 0.081) to (0.139, 0.194). 相似文献
919.
Moon Soo Park Shin Young Kim Soo Young Ryu 《Molecular Crystals and Liquid Crystals》2014,605(1):275-280
The optical film made of liquid crystal molecules can have useful anisotropic optical properties by controlling the alignment of molecules. In order to apply those films to commercial display, we have to know the way to control the thickness, appearance, refractive index, adhesion, and many properties in macroscopic scale. In this presentation, we show how can we control alignment of liquid crystal molecules in macroscopic scale and make the Film Patterned Retarder (FPRTM) used in the polarization type stereoscopic 3D-displays. 相似文献
920.
Taemin Kim Seokwoo Kang Hyocheol Jung Hayoon Lee Donghee Shin Miyeon Park 《Molecular Crystals and Liquid Crystals》2018,662(1):102-108
ABSTRACTDAPCz and DANaPCz have been successfully synthesized and characterized. DAPCz and DANaPCz in film state showed absorption in the range of 322 to 345 nm wavelength and exhibited blue photoluminescence (PL) emission peaks at 428 and 425 nm. PL wavelength of DAPCz is red-shifted by 3 nm than that of DANaPCz, which is due to the carbazole electron donating group of DAPCz. The use of DAPCz in a non-doped OLED device resulted in blue emission with current efficiency of 1.01 cd/A and C.I.E. of (0.26, 0.37). 相似文献