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111.
A new one-pot synthetic route to achieve the preparation of hydroxy and amine binaphthyl and biphenanthryl aryls is here reported. This approach involves the reaction of 1,4-bromoiodobenzene, 4,4′-diiodobiphenyl, and 1,4- and 1,5-diiodonaphthalene with the anions of 2-naphthylamine, 2-naphthol, and 9-phenanthrylamine under irradiation in liquid ammonia. The reactions proceed to afford triaryl derivatives in moderate to good yields (∼45% of 1,4-phenylene- and 1,4-naphthylene-1,1′-dinaphthalen-2-ols as well as 1,4-phenylene-1,1′-dinaphthalen-2-amine and 10,10′-diphenanthren-9-amine). Lower yields (27%) of polyaryl derivatives are obtained by reaction of 4,4′-diiodobiphenyl with anions of 2-naphthol and 9-phenanthrylamine. 相似文献
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Reaction of hydrazine hydrate with aroyl chloride and ammonium thiocyanate under the condition of solid-liquid phase transfer catalysis using polyethylene glycol-600 (PEG-600) as the catalyst yielded 1, 6-diaroyldithiohydrazodicarbonamides 3a—3h in good to excellent yield. 相似文献
115.
Xing‐Zhong Fang Qing‐Xuan Li Zhen Wang Zheng‐Hua Yang Lian‐Xun Gao Meng‐Xian Ding 《Journal of polymer science. Part A, Polymer chemistry》2004,42(9):2130-2144
A new synthetic route to 2,2′,3,3′‐BTDA (where BTDA is benzophenonetetracarboxylic dianhydride), an isomer of 2,3′,3′,4′‐BTDA and 3,3′,4,4′‐BTDA, is described. Single‐crystal X‐ray diffraction analysis of 2,2′,3,3′‐BTDA has shown that this dianhydride has a bent and noncoplanar structure. The polymerizations of 2,2′,3,3′‐BTDA with 4,4′‐oxydianiline (ODA) and 4,4′‐bis(4‐aminophenoxy)benzene (TPEQ) have been investigated with a conventional two‐step process. A trend of cyclic oligomers forming in the reaction of 2,2′,3,3′‐BTDA and ODA has been found and characterized with IR, NMR, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, and elemental analyses. Films based on 2,2′,3,3′‐BTDA/TPEQ can only be obtained from corresponding polyimide (PI) solutions prepared by chemical imidization because those from their polyamic acids by thermal imidization are brittle. PIs from 2,2′,3,3′‐BTDA have lower inherent viscosities and worse thermal and mechanical properties than the corresponding 2,3′,3′,4′‐BTDA‐ and 3,3′,4,4′‐BTDA‐based PIs. PIs from 2,2′,3,3′‐BTDA and 2,3′,3′,4′‐BTDA are amorphous, whereas those from 3,3′,4,4′‐BTDA have some crystallinity, according to wide‐angle X‐ray diffraction. Furthermore, PIs from 2,2′,3,3′‐BTDA have better solubility, higher glass‐transition temperatures, and higher melt viscosity than those from 2,3′,3′,4′‐BTDA and 3,3′,4,4′‐BTDA. Model compounds have been prepared to explain the order of the glass‐transition temperatures found in the isomeric PI series. The isomer effects on the PI properties are discussed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2130–2144, 2004 相似文献
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The effect of solvent on the curing reactions of PMDA/ODA polyamic acids has been investigated using Fourier transform (FT)-Raman spectroscopy. Films of different thicknesses were cured by: (1) doctor blading 15% solids solutions onto glass slides, (2) removing all but the bound NMP, and (3) removing all the N-methypyrrolidinone (NMP). The rate of cure and final degree of conversion of the PMDA/ODA polyamic acid to polyimide increased substantially in the presence of NMP, and this effect was attributed to the plasticizing effect of the solvent. Below a critical solvent concentration, which was estimated to be approximately 40% of the NMP concentration in the bound-solvent limit, the rate of imidization slowed down considerably. Comparison of FT-Raman data for PMDA/ODA polyamic acid: (1) in solution in NMP, (2) complexed with NMP in the solid state, and (3) in the solid state after all the NMP had been removed with water, indicated that intermolecular interactions were greatest in the latter case and weakest in solution. Spectra of PMDA/ODA in NMP solution provide strong evidence for binding of NMP to the amide carbonyl in solution. © 1993 John Wiley & Sons, Inc. 相似文献
118.
Vincent Liégeois Dr. 《Chemphyschem》2009,10(12):2017-2025
The Raman polarized and vibrational Raman optical activity (VROA) backward spectra are simulated for a series of 2,2′‐substituted 1,1′‐binaphthyl compounds presenting a variety of torsion angles between the two naphthalene rings. The substitution prevents free rotation along this torsion angle and the chirality of these compounds is thus called atropisomerism. However, the rotation is not completely frozen so that two different conformations, namely cisoid and transoid, are found and their Raman and VROA signatures are studied. As expected, the Raman spectra are not very sensitive whereas the VROA spectra present more complex patterns, which evolve as a function of the torsion angle between the two naphthalene groups. In particular, our analysis shows that some modes can be used as a probe for the determination of the torsion angle of these molecules in solution. The contributions of both invariants to the VROA backward intensity are also assessed. 相似文献
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普鲁士蓝和苝四甲酸二酐衍生物膜修饰的过氧化氢生物传感器 总被引:2,自引:0,他引:2
以玻碳电极(GCE)为基底,采用恒电位法沉积一层普鲁士蓝(PB),然后将苝四甲酸二酐衍生物(PTC-NH2)自组装到其表面,形成既带氨基功能团,又可有效防止PB渗漏的导电膜.通过静电吸附和共价键合作用固定纳米金和辣根过氧化物酶(HRP)的复合物,从而制得性能优良的过氧化氢(H2O2)生物传感器.采用循环伏安法(CV)和计时电流法,考察了传感器的电化学性能.实验表明,本传感器具有灵敏度高、线性范围宽、检出限低、稳定性好、抗干扰能力强等特点.其线性范围为2.0×10-6~1.4×10-3mol/L;检出限为8.3×10-7mol/L(S/N=3). 相似文献
120.