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71.
72.
In this research, a new fluorinated diamine based on 2,2′‐substituted 1,1′‐binaphthyl units, 2,2′‐bis(2‐amino‐4‐trifluoromethylphenoxy)‐1,1′‐binaphthyl (AFPBN) was synthesized and then used to prepare the corresponding ortho‐linked poly(ether‐imide)s via chemical polyimidization with several aromatic carboxylic dianhydrides. The resulting poly(ether‐imide)s were fully characterized by FT‐IR, NMR, viscosity measurements, gel‐permeation chromatography, UV–vis, X‐ray diffraction, organo‐solubility, thermogravimetric analysis (TGA), and differential scanning calorimetry. Probing optical behavior of the colorless films prepared from these poly(ether‐imide)s demonstrated that they possess a high degree of optical transparency, and UV–visible absorption cut‐off wavelength values were found to be in the range of 404–471 nm. The resulting polymers exhibited excellent organo‐solubility in polar solvents such as dimethylformamide, dimethyl sulfoxide, pyridine, and even tetrahydrofuran. To investigate the heat stability of the samples, their thermograms obtained from TGA were plotted, and for example, it is found that the 10% weight loss temperature of representative polymer AFPBN/3,3′,4,4′‐benzophenonetetracarboxylic dianhydride occurred at 532°C in nitrogen. These poly(ether‐imide)s had glass‐transition temperatures (Tg's) up to 280°C. Two previously prepared analogues of AFPBN, i.e. nonfluorinated diamine DAM1 and para‐linked fluorinated diamine DAM2 used to prepare the corresponding poly(ether‐imide)s, were also considered to compare the results obtained. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
73.
A rapid and stereospecific method using high performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS) for the separation and determination of PSI‐7851 diastereomers in human K2EDTA plasma has been developed. The analytical method involves direct protein precipitation with acetonitrile, followed by separation of the diastereomers on a Luna C18 column, positive mode electrospray ionization and selected reaction monitoring mode mass spectrometry detection. The mobile phase composition and pH were investigated for the resolution of the two diastereomers of PSI‐7851. The optimized method showed good resolution (Rs = 4.8) within short analysis time (approximately 8 min). The assay range was 5–2500 ng/mL for both diastereomers using a 1/x2 weighted linear regression analysis for standard curve fitting. Replicate sample analysis indicated that intra‐ and inter‐day accuracy and precision were within ±15.0%. The recovery of diastereomers from human plasma was greater than 85% and no significant matrix effect was observed. The method was demonstrated to be sensitive, selective and robust, and was successfully used to support clinical studies. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
74.
By combining the blue and orange CPL or functionalized bis-benzoxanethones emitters (S-/R- BN-tCz and S-/R- BN-PXZ ), warm white CP-OLEDs were fabricated using solution-processed single emitting layer strategy. The successful realization of white CP-EL benefited from the same stable binaphthyl chirality and similar rigid structure of the two emissive CPL emitters. The devices exhibited the low turn-on voltage of ≈4.3 V, maximum luminance of ≈10200 cd m−2 and maximum current efficiency of ≈2.0 cd A−1. Most significantly, the devices with CIE coordinates of (0.32, 0.45) displayed intense CP-EL signals in the spectral range of 450 to 650 nm, and showed stable gEL values of ≈10−3 as the luminance increased from 100 to 6000 cd m−2. To the best of our knowledge, this work provides for the first time a simple and feasible strategy to fabricate solution-processed white CP-OLEDs based on the co-doping of the CPL emitters.  相似文献   
75.
Optically active cyclic bis(binaphthyl)s (4ad), which are composed of aromatics, ethers, and ketonic carbonyls, were synthesized through a two‐step nucleophilic aromatic substitution reaction. Bis(binaphthyl) cyclic compounds (4a and 4b) were obtained in moderate yields when difluoride 3a and 3b were employed. On the other hand, bis(binaphthyl)s 4c and 4d were scarcely obtained when 3c and 3d were employed.  相似文献   
76.
A series of novel piperazine phosphoramidate derivatives of 2-arylquinolones were synthesized to improve their physicochemical and biological properties through a facile phosphorylating reaction. Their structures were elucidated by NMR, ESI MS, and HRMS.  相似文献   
77.
The Ir–NHC complex 6 was successfully synthesized from the reaction of axially chiral binaphthyl dibenzimidazolium salt 5 with [Ir(COD)Cl]2 (COD = 1,5‐cyclooctadiene) in tetrahydrofuran in the presence of KOtBu base under reflux. Its unique crystal structure is unambiguously disclosed by X‐ray diffraction. Complex 6 is orthorhombic, with space group P212121, unit cell dimensions a = 12.1406(16) Å, b = 19.110(3) Å, c = 20.312(3) Å, α = β = γ = 90° and volume 4712.6(11) Å3, Z = 4, Dcalc = 1.930 Mg m?3. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
78.
烷氧基对甲硫苯氧基磷酰胺酯的合成与生物活性   总被引:2,自引:0,他引:2  
有机磷化合物;杀虫活性;烷氧基对甲硫苯氧基磷酰胺酯的合成与生物活性  相似文献   
79.
范世彦 《波谱学杂志》1990,7(3):281-288
BETR法是通过CPMG脉冲系列消除手性位移试剂的宽峰,用1H-NMR测定对映体含量的一个新而简单的方法。用此法测定了2'-羟基-2-苄氧基-1,1'联萘对映体含量,并发现随着手性位移试剂Eu(hfc)3/联萘的克分子浓度比的增加,R异构体的亚甲基的二个质子共振峰向低场移动得比S异构体快,但S异构体的亚甲基的二个质子共振峰向低场移动的化学位移差值比R异构体增加快,并提出了由于Bloch-Siegert效应,它们的值都和磁场强度有关。  相似文献   
80.
以MeOP(S)Cl2,甲硫基苯酚和胺类化合物为原料,“一锅反应法”合成了14个通式为MeO(MeSC6H4O)P(S)NHR的磷酰胺酯新化合物,并用元素分析、IR和^1H NMR进行了表征。目标化合物的生物实验表明在0.025%浓度时,杀蚜虫活性为97%-100%。  相似文献   
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