Search

Abstract: We demonstrate that the angular-dependence effect in blue emission top-emitting organic light-emitting diodes (TOLEDs) can be resolved in a very simple and effective way via introducing gratings and filling process. In this method, the shift of the peak emission wavelength with the viewing angle is successfully suppressed in TOLEDs. A desired emission pattern of approximately Lambertian is obtained. Moreover, we can observe almost the same current density and luminance in TOLEDs with and without gratings. Their maximal luminance are 10,776cd/m2 and 11,290cd/m2, respectively. [Copyright &y& Elsevier]

Abstract: Phenylalanine-based bifunctional thiourea derivatives promoted the asymmetric Michael addition of α-fluoro-α-phenylsulfonyl ketones to nitroolefins, affording enantiomerically enriched fluorine-containing multifunctional molecules containing adjoining chiral fluorine-substituted quaternary and tertiary centers in good yields and enantioselectivities. [Copyright &y& Elsevier]

Abstract: A simple and novel method to the synthesis of 3-fluoro-4-aryl-2-pyridone from a Michael-adduct of fluoronitroacetate and α,β-unsaturated ketone is reported. With (NH4)2CO3 as the N-source and TsOH as the promoted acid, a series of fluorinated-pyridones was obtained with moderate to good yields. [Copyright &y& Elsevier]

Abstract: Primary amines catalyzed the asymmetric Michael addition of ethyl 2-fluoro-2-nitroacetate to enones to provide chiral α-fluoro-α-nitro ester ketones with two contiguous stereogenic centers, one of which is a fluorinated quaternary chiral center, with excellent enantioselectivities and in moderate to good yields. [Copyright &y& Elsevier]

Abstract: The enantioselective Michael addition of α-cyanoketones to α,β-unsaturated trichloromethyl ketones was firstly reported. With a phenylalanine-derived bifunctional piperazine/thiourea catalyst, a series of α-trichloromethyldihydropyrans were obtained with up to 95% ee and 99% yield. [Copyright &y& Elsevier]

The next generation of optoelectronic devices requires transparent conductive electrodes to be flexible, inexpensive and compatible with large scale manufacturing processes. We report an ultrasmooth, highly conductive and transparent composite electrode on a flexible photopolymer substrate by employing a template stripping method. A random silver nanowire (AgNW) network buried in poly(3,4ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film constituted the composite electrode. Besides the effectively decreased surface roughness, its sheet resistance and transmittance are comparable to those of conventional PEDOT:PSS electrode. As a result, the efficiency of the OLEDs based on the composite electrode exhibited 25% enhancement compared to the OLEDs with conventional PEDOT:PSS electrode. Moreover, the performance of the flexible OLEDs remains stable after over one hundred bending cycles. [ABSTRACT FROM AUTHOR]