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Andrew J. Thompson Dr. Jerome Dabin Javier Iglesias‐Fernández Dr. Albert Ardèvol Dr. Zoran Dinev Assoc. Prof. Spencer J. Williams Dr. Omprakash Bande Dr. Aloysius Siriwardena Carl Moreland Dr. Ting‐Chou Hu David K. Smith Prof. Harry J. Gilbert Prof. Carme Rovira Prof. Gideon J. Davies 《Angewandte Chemie (International ed. in English)》2012,51(44):11171-11171
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Martin Pomerantz Whe-Narn Chou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract A series of N-phenyl-P,P,P-triarylphospha-λ5-azenes (1) as well as their l5N labeled analogs was synthesized. The 13C, 31P, and 15N NMR spectra of this series and those of two other series of related compounds, namely triarylphosphines (2) and triarylphosphine oxides (3), were measured and are reported. Many satisfactory correlations using the mono-substituent parameter (MSP) and the Taft dual-substituent parameter (DSP) treatments with the 13C substituent chemical shifts (SCS), 31P SCS, 15N SCS and the one bond P-N, P-C and C-N coupling constants were observed and will be discussed. Thus, for example, the 31P and 15N chemical shifts in 1 correlated with [sgrave]?with negative slopes while the 31P chemical shifts in 3 correlated with those in 1 with a slope of 2.0. The 13C chemical shifts in 1 correlated excellently with the corresponding ones in 3 with slopes very close to unity. The substituent effects on the chemical shifts of the various nuclei were shown to be mainly due to changes in the charge distribution on those nuclei. In 1 the one bond P-N and P-C coupling constants correlated with [sgrave]p and [sgrave]R respectively. The one bond P-C coupling constants of 1 correlated quite well with those of 3 with a slope of 0.93 while the corresponding correlation of 1 with 2 was quite poor. Taft DSP treatment of 1JPCin 1 and 3 were quite similar, ρI and ρR were both negative and ρR was much larger than ρI. Series 2 showed behavior which was different from that shown by 1 and 3 but similar to that shown by other systems with a lone electron pair on the atom bound to the phenyl ring. The substituent effects on the one bond P-N, P-C and C-N coupling constants will be discussed in terms of bonding and hybridization changes between the directly bonded nuclei. 相似文献
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Flash vacuum pyrolysis of 2‐methoxy‐N‐(arenylidene)anilines 2a‐g at 700 °C and 1 × 10‐2 Torr gave the corresponding 2‐arylbenzoxazoles 1a‐g . 相似文献
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Ping‐Tsung Huang Cheng‐Wei Chou Mei‐Ying Chang Wen‐Yao Huang Chih‐Chien Lee Yu‐Kai Han Shun‐Wei Liu 《中国化学会会志》2011,58(3):326-331
The performance of a blue polymer light‐emitting diodes (PLED) was significantly improved by doping a controlled amount (<1%) of a hole transport molecule N,N′‐bis‐(1‐naphthyl)‐N,N′‐diphenyl‐1,1′‐biphenyl‐4,4″‐diamine (NPB) into the emitting layer. Hole carrier mobility of the blue emitting polymer, BP105 (trade name of The Dow Chemicals Co.), increased from 5.27 × 10‐7 cm‐2/Vs of the pristine BP105 to 1.80 × 10‐6 cm‐2/Vs with the addition of 1% NPB in BP105. The enhanced carrier mobility greatly promoted performance of a blue PLED device with a device structure of ITO/PEDOT:PSS/BP105+x% NPB/LiF/Ca/Al. Luminance increased from 573 cd/m2 to 2,720 cd/m2 at 6V and efficiency increased from 1.1 lm/W to 1.6 lm/W at 1,000 cd/m2 with 1% NPB in BP105. The most important improvement was an increase in the lifetime of the blue device from 80 to 120 hours at an initial luminance of 400 cd/m2. We found that by choosing the appropriate dopant with good energy alignment and controlled dopant concentration, the performance of a blue PLED device could be greatly improved. 相似文献
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