液晶光定向层材料

本文综述了近10年来液晶显示用光定向层材料领域的研究现状和进展情况，主要概述了光降解型、光致异构型、光交联型以及自组装等材料，并对目前报道的液晶光定向机理进行了总结和归纳。     

《化学通报》网络版(Chemistry Online)2002年第6期论文摘要

[Ｗ 0 41 ]苄基型醇催化氢解反应ＣａｔａｌｙｔｉｃＨｙｄｒｏｇｅｎｏｌｙｓｉｓｏｆｔｈｅＢｅｎｚｙｌ ｔｙｐｅＡｌｃｏｈｏｌｓ刘晓晖　王新宏　卢冠忠 (华东理工大学工业催化研究所　上海　 2 0 0 2 3 7)简要介绍了苄基型醇催化氢解的方法、催化剂和催化反应的机理。内容包括了用分子氢催化氢解反应 ,取代基团、溶剂及卤代芳烃等因素对直接催化氢解反应的影响 ;用非分子氢的催化转移氢解反应 ,非分子氢氢源给氢能力的强弱 ;有机电化学在醇氢解文献的应用等。Ｔｈｅｍｅｔｈｏｄｓ,ｃａｔａｌｙｓｔｓａｎｄｒｅａｃｔｉｏｎｍｅｃｈ…     

NAD（P）H辅酶模型的Mg^2＋离子催化条件下还原N—芳基芴亚胺反…

对Ｈａｎｔｚｓｃｈ酯在Ｍｇ＾２＋存在和不存在吓还原Ｎ－芳基芴亚胺的反应进行了研究，并与ＢＮＡＨ的类似还原做了系统的比较，研究结果表明：Ｍｇ＾２＋在该还原反应中起亲电催化剂的作用；还原能力较ＢＮＡＨ弱的Ｈａｎｔｚｓｃｈ酯在反应中所呈现的强的反应性是由于其３，５－位两个极性羰基氧通过静是作用降低过渡态的能量的缘故，本文反应属Ｈ一步转移机理。     

聚（2,5—二甲氧基对苯乙炔）的可溶性前聚物合成及表征

研究了合成聚（２，４－二甲氧基对苯乙炔）的有机可溶性前聚物的反应条件与单体转化率和前聚物产率的关系。实验结果表明：ＮａＯＨ是聚合反应的有效引发剂，适宜的反应条件为：单体与ＮａＯＨ摩尔比为１：１，单体浓度０．０５－０．２ｍｏｌ／Ｌ，聚合时间２ｈ，温度低５℃，正己烷、石油醚作为有机提取剂可有效提高前聚物产率。用ＩＲ、ＵＶ－Ｖｉｓ＇＾ＨＮＭＲ，ＴＧＡ和 ＤＳＣ对前聚物进行了表征。     

苯乙烯一氧化碳高聚物的合成与表征

阳离子钯-配体催化剂的的存在下,一氧化碳与烯烃的均相共聚形成新型环保材料聚酮,共聚单体一氧化碳价格低廉,生成的共聚物主链上存在具有反应活性的羰基官能团,与烯烃均聚物比较,具有光降解性能以及生物降解性能,     

烟酰胺辅酶模型对N—芳基芴亚胺的酸催化还原反应的研究

报道了５种Ｎ－芳基芴亚胺在酸性条件下被烟酰胺辅模型（Ｈａｎｔｚｓｃｈ酯，ＢＮＡＨ）还原的反应。结果表明：亚胺的结构，酸的强度以及溶剂的不同均会影响亚胺的还原效率本文结合反应的结构效应，溶剂效应和同位素效应，对其可能的酸催化氢负离子转移机理进行了讨论。     

钯(Ⅱ)催化CO/乙烯的交替共聚

聚酮是一种新型光降解材料,近二十年来在国内外引起了广泛的兴趣,世界上许多大化学公司对开发聚酮新产品投入了极大的热情,Shell公司和BP公司都相继实现了工业化,其核心技术是催化剂,其中Shell公司在八十年代初期开发的钯(Ⅱ)-双膦催化剂是过渡金属催化剂研究上的一个突破性进展[1,2],而贵金属钯的昂贵价格限制了聚酮向大规模工业化发展,为此吸引了众多的学者对共聚机理进行深入研究,以期寻找物美价廉的催化剂,但由于反应体系的复杂性以及催化剂中间态难以捕捉和表征的特点,至今人们提出的反应机理依据明显不足.     

meso—四（4—磺基苯基）卟啉（TPPS）在水及胶束体系中的二聚行为研究

研究了ｍｅｓｏ－四（４－磺基苯基）卟啉在胶束，ＫＣｌ水溶液中的电子吸收光谱变化，计算了ＴＰＰＳ的二聚常数ＫＤ，用分光光度法研究了ＴＰＰＳ在ＫＣｌ水溶液中的二聚反应动力学，提出了与实验结果相吻合的二聚机理。根据温度对二聚平衡的影响。     

［Fe（Phen）_3］（ClO_4）_3与Na_2SO_3在室温下的固相氧化还原反应

本文研究室温下［Ｆｅ（Ｐｈｅｎ）３］（ＣｌＯ４）３·Ｈ２Ｏ与Ｎａ２ＳＯ３发生的固－团相氧化还原反应．用Ｍｏｓｓｂａｕｅｒ谱、ＸＲＤ、ＩＲ、元素分析和磁化率测定等手段表征了反应２４ｈ后的团相产物．实验表明，室温下该反应速度快，反应进行完全．     

聚（2，5－二甲氧基对苯乙炔）的可溶性前聚物合成及表征

研究了合成聚（２，５－二甲氧圣对苯乙炔）的有机可溶性前聚物的反应条件与单体转化率和前聚物产率的关系。实验结果表明：ＮａＯＨ是聚合反应的有效引发剂。适宜的反应条件为：单体与ＮａＯＨ摩尔比为１：１，单体浓度０．０５～０．２ｍｏｌ／Ｌ聚合时间２ｈ，温度低于５℃。正已烷、石油醚作为有机提取剂可有效提高前聚物产率，用ＩＲ、ＵＶ－Ｖｉｓ、￣１ＨＮＭＲ、ＴＧＡ和ＤＳＣ对前聚物进行了表征。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.