6-氯-8-溴螺(吲哚啉-2,2''''[2H]苯并[b]吡喃)的合成及光致变色性能研究

合成了一系列新型的6-氯-8-溴-螺吡喃光致变色化合物, 并用核磁共振氢谱、红外光谱、质谱和元素分析对目标化合物进行了表征, 利用X射线单晶衍射仪测定了1′,5′-甲基取代化合物的晶体结构.通过UV-Vis光谱对化合物在不同溶剂中的光致变色性能进行了研究, 讨论了溶剂和结构对光致变色性能的影响.在极性较大的溶剂中, 光致变色现象明显; 给电子能力较强的基团和强极性溶剂使最大吸收波长蓝移.     

6-氯-8-溴螺（吲哚啉-2，2′[2H]苯并[b]吡喃）的合成及光致变色性能研究

合成了一系列新型的6-氯-8-溴-螺吡喃光致变色化合物,并用核磁共振氢谱、红外光谱、质谱和元素分析对目标化合物进行了表征,利用X射线单晶衍射仪测定了1′,5′-甲基取代化合物的晶体结构.通过UV-Vis光谱对化合物在不同溶剂中的光致变色性能进行了研究,讨论了溶剂和结构对光致变色性能的影响.在极性较大的溶剂中,光致变色现象明显;给电子能力较强的基团和强极性溶剂使最大吸收波长蓝移.     

一种逆向光致变色螺吡喃化合物的光消色关环反应机理研究

研究了逆向光致变色化合物１′－十八烷基－３′，３′－二甲基－６，８二硝基螺［２Ｈ－１－苯并吡喃－２，２′－吲哚啉］的可见光消色机理。通过吸收光谱测定其在不同溶剂及含不同添加剂时，可见光照射后有色体［ＭＣ］关环的光量子产率。结果表明Ｏ２、三苯基胺等三线态猝灭剂对关环反应光量子产率几乎没有影响。据此提出关环反应主要是通过单线态的途径进行的结论。     

吲哚啉螺吡喃化合物光致变色性能的研究及在生物细胞成像中的应用

吲哚啉螺吡喃是一种重要的光致变色化合物,由于具有良好的变色回复性、抗疲劳性而得到广泛的关注.本文合成了1′-羟乙基-3′,3′-二甲基吲哚啉-6-硝基螺吡喃,研究了该化合物在紫外-可见光交替照射下紫外吸收强度的变化,并测试了光照前后化合物的荧光光谱.在开环态时,化合物具有优良的荧光性能,可以成功应用于细胞成像,在活细胞中可获得清晰的荧光成像图,同时也可以发挥螺吡喃光致变色可循环、耐疲劳等优势.     

三种苯并噻吩缩氨基硫脲类化合物的固态光致变色性能研究

本文通过结构修饰,在苯并噻吩缩氨基硫脲侧链的同一位点引入具有不同共轭性的取代基(烯丙基、环已基和苯基),合成了三种具有固态光致变色性能的1-(苯并噻吩-2亚甲基)-4-取代基-氨基硫脲类化合物,并对化合物的结构进行了表征,同时利用紫外-可见吸收光谱和光致变色动力学分析了三种化合物的光致变色性能、热力学变化和抗疲劳性,探...     

1,2,3,4-四(6,′7′,-二甲基苯并噁唑)环丁烷光谱特性研究

本文测定并对1,2,3,4-四(6′,7′-二甲基苯并嗯唑)环丁烷(1)及其模型化合物反-1,2-二(6′,7′-二甲基苯并(口恶)嗯唑-1′,3′-基-2′)乙烯(2),1,2-二(6′,7′-二甲基苯并(口恶)唑-1′,3′-基-2′)乙烷(3),2-甲基苯并(口恶)唑(4)的紫外吸收光谱和荧光发射光谱进行对比。研究了化合物1由于跨环共轭效应所引起的电子光谱的变化,并从溶剂效应及晶体结构进行了探讨。     

新型联萘酚衍生物手性固定相的性能

以R-联萘酚为手性源合成了3,3′-二对苯甲酸-2,2′-二甲氧基-1,1′-二萘,将其键合到3-氨基丙基硅烷基化硅胶上制成手性固定相。采用扫描电镜、红外光谱和元素分析法对联萘酚衍生物手性固定相进行表征。采用高效液相色谱法探究联萘酚衍生物手性固定相对手性化合物和位置异构体的拆分性能,以正己烷-异丙醇溶液为流动相,紫外检测波长为254nm。结果表明,该固定相使5种手性化合物得到拆分和8种位置异构体得到不同程度的分离。     

新型双螺噁嗪分子的合成及性能

设计合成了3个双螺噁嗪化合物, 采用核磁共振谱、红外光谱和高分辨质谱对这些化合物进行了表征. 测试了光照前后化合物在不同溶剂中的紫外吸收光谱、荧光光谱以及在高分子薄膜中的消色动力学曲线. 结果表明, 目标化合物均具有良好的光致变色性能和耐疲劳度, 在材料、分子开光及生物探针领域有潜在的应用前景.     

一个新颖的光磁性二噻吩乙烯铜配合物的合成和光致变色性质

合成了一个新颖的金属铜和1,2-双(2′-甲基-5′-(4″-吡啶基)-3′-噻吩) 全氟代环戊烯 (BM-4-PTP)配合物,并用红外、核磁共振、元素分析进行了表征。研究了配合物在晶体相的光致变色性质和磁性性质。在光激发下,配合物[Cu(BM-4-PTP)₂(CF₃COO)₂](THF)₂(H₂O)₂(1)在晶体相显示出可逆的光异构反应。有趣的是,伴随着光致变色反应,配合物1的开环体(1o)和闭环体(1c)在晶体相还显示出磁性差异,1o和1c的磁化率可逆地发生变化,说明由于开环异构体和闭环异构体的π共轭结构不同,通过配体BM-4-PTP桥联的铜离子之间的相互作用可以被光引发。     

对称吡啶基二噻吩乙烯光致变色化合物的合成与性能

二噻吩乙烯光致变色化合物具有热稳定性高、抗疲劳性好等优点。 本文以2-甲基噻吩为原料,经过Suzuki偶联、傅克酰基化、McMurry环合3步反应制备1,2-二(5-吡啶基-2-甲基噻吩-3-基)环戊烯,总收率61%。 所有中间体及目标产物均已通过核磁共振、质谱、红外光谱等技术手段表征。 该合成方法具有合成步骤少、简便、总收率高、易于工业化生产等优点。 利用紫外-可见吸收光谱、荧光光谱对该化合物及其与镍离子、锡离子相互作用的光致变色性能以及应用进行了研究。 对称吡啶基二噻吩乙烯通过与金属配位在紫外光的照射前后显示出不同的颜色和光谱吸收,可以用作新型金属离子探针。     

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.