从2-(2-吡啶)-1,3-丙二醇衍生出的一些新的吡啶化合物

本文报道了2-(2-吡啶)-1,3-丙二醇及其衍生物的一些新的反应,以此得到了一系列新的1,3-二取代2-(2-吡啶)丙烷和3-取代2-(2-吡啶)丙烯-1化合物,并讨论了这些化合物的光谱数据。     

微波辐射下一步合成吡啶和吡喃衍生物

吡啶衍生物具有重要的生物活性 ,用作药物和农用化学品如ｈｅｒｂｉｃｉｄｅｓ[1 ] 。有些吡啶衍生物具有荧光性质 ,已被用于液晶工业。一些 2 氨基 4Ｈ吡喃具有光化学活性[2 ] 。多取代的四氢吡喃还是许多天然产物的基本结构单元[3] 。 4 芳基四氢吡喃可以转变成吡啶衍生物 ,后者是药物上重要的钙离子通道调节剂[4～6] 。自从ＳａｋｕｒａｉａｎｄＭｉｄｏｒｉｋａｗａ[7] 于 1 968年第一次报道在醋酸铵存在下丙二腈与α、β 不饱和酮反应得到吡啶衍生物以来 ,丙二腈与α、β 不饱和酮反应用于吡啶和吡喃衍生物的合成已愈来愈引起人们兴趣…     

1,4—二氢吡啶及其衍生物电化学反应机理的研究

研究了１１种１，４－二氢吡啶及其衍生物在乙腈溶剂中和铂盘电极上的电化学行为。实验结果表明：１，４－二氢吡啶及其衍生物在铂盘电极上的反应是受扩散和化学反应速率控制的两电子不可逆氧化过程，经连续两步失电子脱氢后形成相应的吡啶。用紫外吸收光谱电化学方法观测了电化学氧化过程。并与化学氧化产物的紫外光谱作了比较，证明１，４－二氢吡啶的电化学氧化产物与化学氧化产物一致。因此，电化学氧化是一种不需加化学试剂可使     

含吡啶基团的双极主体材料的合成、性能与蓝光电致磷光器件研究

吡啶类衍生物具有较好的电子传输性能和较高的三线态能级,在有机电致发光中一般用来构建电子传输材料或主体材料中的电子传输单元.本文通过将吡啶的2,6位与三苯胺或N-苯基-咔唑的邻位连接设计合成了两个基于吡啶的双极主体材料DTPAPPy和DCzPPy.它们的三线态能级分别为2.64和2.70eV.以它们作为主体材料制备的基于Firpic的蓝光磷光器件最大电流效率分别为15.4和25.3cd/A.     

四苯氧基酞菁钴及其吡啶衍生物的配合物的合成和性质

合成了2,2′,2″,2-四苯氧基酞菁钴配合物[TPhOPeCo(Ⅱ)]及其与吡啶衍生物的配合物[TPhOPcCo(Ⅱ)(L)_2](L=Py,MePy,AnPy),测定了其IR、UV-Vis、热稳定性及其在DMF中的氧化还原半波电位、电子转移速度常数和在不同电位电解下的电子吸收光谱。     

5-取代氧化呋咱并[3,4-b]吡啶衍生物的合成与表征

以廉价易得的2,6-二氯吡啶为原料,经过硝化、叠氮化、热解环化步骤得到中间体[1,2,5]噁二唑并[3,4-e]四唑并[1,5-a]吡啶-3-氧化物(4b),再与浓硫酸/硝酸钾、甲醇钠和甲胺水溶液反应分别得到5-取代的氧化呋咱并[3,4-b]吡啶衍生物5~7。 研究了化合物4b结构的稳定性,发现其中的氧化呋咱环在强酸性、强碱性和弱碱性条件下较稳定,而吡啶环与叠氮基形成的四唑环结构则不太稳定。     

新型(4R,5R)-2-苯基-1,3-二氧戊环-4,5-二(2-吡啶甲氧基)甲烷的合成

设计并合成了一种新型以L-酒石酸为手性源的具有C2-对称轴的吡啶衍生物手性配体——(4R,5R)-2-苯基-1,3-二氧戊环-4,5-二(2-吡啶甲氧基)甲烷,其结构经1H NMR和MS表征。     

吡啶硝化衍生物的合成及应用

综合评述了吡啶类化合物的硝化合成方法及近年来的研究进展，对其中较重要的氮氧化－硝化法进行了讨论，并介绍了该类衍生物在农药、医药、有机合成等方面的应用情况。     

含噻二唑硫醚的槟榔碱新衍生物的合成及舒张血管活性

槟榔碱衍生物;四氢吡啶;噻二唑;合成;舒张血管活性     

N-氧化吡啶-2-甲醛单缩1,2-丙二胺Schiff碱镍配合物的晶体结构

由于N-氧化吡啶及其衍生物具有独特的配位性质~[1]以及其金属配合物可作为药物~[2],因此人们对其进行了广泛的研究~[3～8]. 本文继合成N-氧化吡啶-2-甲醛与1,2-丙二胺的双缩Schiff碱铜配合物并测定了其晶体结构之后~[8],又得到了一个新的N-氧化吡啶-2-甲醛单缩1,2-丙二胺镍的配合物.经X射线     

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.     

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.     

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.     

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.     

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.