微波法快速合成光致变色螺(口恶)嗪

螺嗪(Ｓｐｉｒｏｘａｚｉｎｅ)是20世纪70年代在螺吡喃基础上发展起来的一类具有良好光致变色性能的化合物,具有很高的抗疲劳性和光稳定性,具有潜在的商业应用前景[1-4],可用作光信息储存材料和光致变色镜片(ＰｈｏｔｏｃｈｒｏｍｉｃＬｅｎｓ)。6 哌啶取代的吲哚啉螺萘并嗪[5-11]相对于未取代的母体化合物具有更优异的光致变色性能,但是文献中的合成方法步骤繁琐、反应时间长、产率较低。本文利用微波合成了6 哌啶基(氰基)吲哚啉螺嗪,合成路线如下:1　实验部分1.1　仪器和试剂显微熔点仪(四川大学科仪厂),温度计未经校正;美国Ｐ…     

新型含二茂铁基螺苝嗪类光致变色化合物的合成及其光谱研究

合成了一种新的含二茂铁基螺 嗪类光致变色化合物 ,并研究了其吸收光谱和荧光光谱。发现在分子内引入二茂铁基团提高了热不可逆性 ,发生光致变色反应前后化合物结构的不同对其荧光特性影响很大     

新型含二茂铁基螺噁嗪类光致变色化合物的合成及其光谱研究

合成了一种新的含二茂铁基螺噁嗪类光致变色化合物，并研究了其吸收光谱和荧光光谱。发现在分子内引入二茂铁基团提高了热不可逆性，发生光致变色反应前后化合物结构的不同对其荧光特性影响很大。     

光致变色聚合物研究进展

本文主要介绍了9类光致变色聚合物的研究状况,包括光致变色螺吡喃聚合物、螺噁嗪聚合物、二芳基乙烯光致变色聚合物、偶氮苯类光致变色聚合物、苯氧基萘并萘醌光致变色聚合物、俘精酰亚胺光致变色共聚物、硫靛光致变色共聚物、双硫腙光致变色聚合物以及二氢吲嗪光致变色聚合物等。讨论了聚合物的合成、光致变色性质、影响聚合物性质的因素,并对光致变色聚合物未来的研究重点和方向作了展望。     

光致变色聚合物研究进展

本文主要介绍了9类光致变色聚合物的研究状况,包括光致变色螺吡喃聚合物、螺嗪聚合物、二芳基乙烯光致变色聚合物、偶氮苯类光致变色聚合物、苯氧基萘并萘醌光致变色聚合物、俘精酰亚胺光致变色共聚物、硫靛光致变色共聚物、双硫腙光致变色聚合物以及二氢吲嗪光致变色聚合物等。讨论了聚合物的合成、光致变色性质、影响聚合物性质的因素,并对光致变色聚合物未来的研究重点和方向作了展望。     

光致变色聚合物研究进展

本文主要介绍了9类光致变色聚合物的研究状况,包括光致变色螺吡喃聚合物、螺噁嗪聚合物、二芳基乙烯光致变色聚合物、偶氮苯类光致变色聚合物、苯氧基萘并萘醌光致变色聚合物、俘精酰亚胺光致变色共聚物、硫靛光致变色共聚物、双硫腙光致变色聚合物以及二氢吲嗪光致变色聚合物等.讨论了聚合物的合成、光致变色性质、影响聚合物性质的因素,并对光致变色聚合物未来的研究重点和方向作了展望.     

螺噁嗪类光致变色化合物的合成研究进展

光致变色螺噁嗪;双光致变色螺噁嗪;螺噁嗪聚合物;合成;微波合成     

螺噁嗪化合物的合成及其光致变色性能的研究

合成了3种新型的螺噁嗪化合物,并通过IR,MS,1H NMR对其结构进行了表征。研究了1位和9’位上取代基对螺噁嗪光致变色性能的影响;不同溶剂对螺噁嗪最大吸收波长的影响;对螺噁嗪的热褪色速率进行了动力学的研究。结果表明,当螺噁嗪1位的取代基为柔性结构,9’位连接能形成更稳定共轭体系的取代基时有利于开环体热稳定性的提高。     

苯并噻唑螺萘并噁嗪类化合物的微波合成与性质

以苯并噻唑衍生物、1-亚硝基-2-萘酚为原料,三乙胺为催化剂,无水乙醇为溶剂,采用微波辐射法合成了苯并噻唑螺萘并噁嗪光致变色化合物.通过元素分析,IR,MS,1H NMR对结构进行了表征,并用紫外分光仪研究了溶剂效应和荧光分光光度计研究了荧光效应,结果表明该类化合物具有较好的荧光性能,其开环体的λmax与溶剂的极性常数呈较好的线形相关性.     

螺噁嗪光致变色反应机理研究进展

20世纪80年代中期以来, 关于螺噁嗪在光致变色过程中的光化学和光物理现象的研究非常活跃. 综述了近20年来对溶液中的螺噁嗪、晶体螺噁嗪以及固体介质中的螺噁嗪的光致变色机理研究结果, 同时介绍了实验研究方法和理论研究方法在螺噁嗪光致变色过程研究中的应用, 分析了取代基对光致变色性质的影响. 阐述了机理研究对新型螺噁嗪设计合成的重要指导意义.     

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%.     

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.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.