薁并[2,1-b]吡啶的简便合成方法

以2-氨基-1-乙酰基薁-3-甲腈和β-二羰基化合物为原料,在1-甲基咪唑-3-丙基磺酸硫酸氢盐的作用下,一锅法合成了薁并[2,1-b]吡啶类衍生物。该反应收率良好、操作简单、条件温和。产物的结构通过红外光谱、核磁共振谱和元素分析证实。     

Synthesis of D–A low-bandgap polymer-based thieno[3,4-b]pyrazine and benzo[1,2-b:4,5-b′]dithiophene for polymer solar cells

Three D–A low-bandgap polymer-based benzo[1,2-b:4,5-b′]dithiophene (BDT) and thieno[3,4-b]pyrazine (TP) unit with different substituents were synthesized using Stille coupling. The substituent effects were explored. It is found that attaching the phenyl group at the 2,3-positions of thienopyrazine unit is beneficial to good coplanarity and regularity of molecular packing. Meanwhile, attaching the longer alkoxyl side chain at BDT unit or phenyl group at the 2,3-positions of thienopyrazine unit had the relatively deep HOMO (LUMO) energy levels. The three D–A polymers showed good thermal stability and exhibited broad absorption, low bandgap, and order packing structure. As a result, the highest PCE of 1.50 % was achieved for the polymer P2 with the substituents, including hexyldecyloxyl at the BDT unit and phenyl at the TP unit.     

Synthesis and photovoltaic properties of alternative copolymers of benzo[1,2-b:4,5-b′]dithiophene and thiophene

Two conjugated polymers containing benzodithiophene (BDT) unit and the unit of thiophene or thieno[3,2-b]thiophene, P(BDT-T) and P(BDT-TT), were synthesized by Pd-catalyzed Stille coupling method. The UV–Vis absorption, thermal, and electrochemical properties of the two polymers were characterized. Photovoltaic properties of the polymers were studied by using the polymers as donor and PC₇₀BM as acceptor with a weight ratio of polymer: PC₇₀BM of 1:1.5. The power conversion efficiencies of the PSC devices based on P(BDT-T) reached 2.05% with an open-circuit voltage of 0.75 V, a short-circuit current of 4.5 mA cm⁻², and a fill factor of 0.61, under the illumination of AM1.5, 100 mW cm⁻².     

[1]-萘并[1,2-b]、[2,1-b]氧杂卓并[3,4-b]喹啉-15(8H)-酮的合成及量化计算

以邻硝基苯甲醛为起始原料,经还原、Friedlander缩合、溴化反应得到中间体2-溴甲基-3-喹啉酸乙酯,再将其分别与α-萘酚和β-萘酚一锅法高产率地合成2-(α-萘氧甲基)-3-喹啉酸和2-(β-萘氧甲基)-3-喹啉酸,然后分别通过Eaton’s Reagent环化,发生分子内Friedel-Crafts反应又得到2种新型闭环产物:[1]-萘并[1,2-b]氧杂卓并[3,4-b]喹啉-15(8H)-酮和[1]-萘并[2,1-b]氧杂卓并[3,4-b]喹啉-15(8H)-酮。合成产物经1H-NMR、MS和IR确认,并测定了在三氯甲烷中的紫外光谱和固体荧光光谱,并对其荧光光谱进行量子化学计算模拟。     

Synthesis and simultaneously enhanced photovoltaic property of poly[4,4,9,9-tetra(4-octyloxyphenyl)-2,7-indaceno[1,2-b:5,6-b′]dithiophene-alt-2,5-thieno[3,2-b]thiophene]

An alternating conjugated polymer derived from 4,4,9,9-tetra(4-octyloxyphenyl)indaceno[1,2-b:5,6-b′]dithiophene and thieno[3,2-b]thiophene was synthesized by Stille coupling reaction. The copolymer shows extensive absorption from 360 nm to 590 nm with optical band gap of 2.12 eV. The highest occupied molecular orbit (HOMO) and the lowest unoccupied molecular orbit (LUMO) energy levels of the copolymer, determined by cyclic voltammetry (CV), are about ?5.29 eV and ?3.01 eV, respectively. A field-effect hole mobility of 8.1 × 10^?4 cm²/(V s) and an on/off ratio of 2.0 × 10³ are obtained in the field-effect transistors based on the copolymer. The J_sc, V_oc and FF of the polymer photovoltaic cells (PVCs) based on the copolymer were enhanced simultaneously via the inserting of alcohol soluble conjugated polymer interlayer between active layer and metal cathode, and the maximal power conversion efficiency of 4.19% was achieved in the modified devices under an AM 1.5 simulator (100 mWcm^?2).     

咪唑并[2,1-b]噻唑衍生物的合成及生物活性进展

根据环上取代基的不同咪唑并[2,1-b]噻唑衍生物具有多种多样的生物活性。通过对咪唑并[2,1-b]噻唑衍生物合成方法的不同进行分类,综述了近年来咪唑并[2,1-b]噻唑衍生物的合成及其生物活性,结果表明在咪唑并噻唑环上引入药理活性基团会增强其生物活性。咪唑并[2,1-b]噻唑环一般由Hanzstch方法合成,近年来也出现了一些新的合成方法,如Sonogashira、Suzuki反应和金属催化芳基化,对这些新方法合成咪唑并噻唑环及其衍生物也进行了综述。     

咪唑并[2,1-b]噻唑衍生物亚磺酰基化探索合成

以6-芳基咪唑并[2,1-b]噻唑并苯等底物与氟虫腈类似物二硫醚为起始原料,探索合成具有潜在生物活性的亚磺酰基咪唑杂环化合物。研究表明,在乙醇介质中,60℃,用I_2/H_2O_2催化氧化,合成产物的产率高,区域选择性好,用时少。通过红外光谱、核磁共振氢谱、核磁共振碳谱、X-单晶衍射仪、高效液质联用仪等分析方法对合成产物的结构进行了表征,证明了合成方法的可靠性。     

咪唑[2,1-b][1,3,4]噻二唑类ALK5抑制剂3D-QSAR研究

TGF-β信号的转导与纤维化疾病的发生及癌细胞的侵入和转移高度相关,而TGF-β信号通路中的重要节点ALK5是治疗这些疾病的理想靶标。本文针对31个新型咪唑[2,1-b][1,3,4]噻二唑类ALK5抑制剂,分别运用Co MFA和Co MSIA两种经典方法进行了3D-QSAR研究,并获得了预测能力较优的两个模型(Co MFA:q2=0.803,r2=0.969;Co MSIA:q2=0.765,r2=0.938)。3D-QSAR模型三维等值图揭示了一些结构特性与抑制活性的关系,为该类药物结构改造提供了有效信息,可减少设计合成工作量,提高新药研发成功的可能性。     

Synthesis and photovoltaic properties of D-π-A copolymers based on thieno[3,2-b]thiophene bridge unit

Three D-π-A copolymers containing thieno[3,2-b]thiophene (TT) bridge and BDT, carbazole, fluorene as D units and benzothiadiazole as A unit were synthesized and characterized. These copolymers of PBDT-tt-BT, PC-tt-BT and PF-tt-BT exhibited enough high thermal stabilites and good solubilites in chloroform and dichlorobenzene. Among the copolymers, with the increase of the electron-donating abilities of the D units from fluorene to carbazole further to BDT, the absorption spectra of PF-tt-BT shows blue shift and that of PBDT-tt-BT shows red shift comparing to that of PC-tt-BT in their solutions and films. Meanwhile, by electrochemical cyclic voltammetry measurements we found the HOMO levels vary in the same trench according to their electron-donating abilities. Under the illumination of AM 1.5G, 100 mW/cm², power conversion efficiency (PCE) of the PSCs based on these copolymers as donors and PC₇₀BM as acceptor were measured and PBDT-tt-BT shows a higher efficiency of 4.91% than PC-tt-BT and PF-tt-BT based devices mostly due to its higher hole mobility and broader absorption range. These results indicate that PBDT-tt-BT is a promising photovoltaic polymer donor material for efficient PSCs.     

Synthesis and Antimicrobial Evaluation of Some Novel Bis-α,β-Unsaturated Ketones,Nicotinonitrile, 1,2-Dihydropyridine-3-carbonitrile,Fused Thieno[2,3-b]pyridine and Pyrazolo[3,4-b]pyridine Derivatives

The title compounds were prepared by reaction of 1,1′-(5-methyl-1-phenyl-1H-pyrazole-3,4-diyl)diethanone (1) with different aromatic aldehydes 2a–c, namely Furfural (2a), 4-chlorobenzaldehyde (2b) and 4-methoxybenzaldhyde (2c) to yield the corresponding α,β-unsaturated ketones 3a–c. Compound 3 was reacted with malononitrile, 2-cyanoacetamide or 2-cyanothioacetamide yielded the corresponding bis[2-amino-6-(aryl)nicotinonitrile] 4a–c, bis[6-(2-aryl)-2-oxo-1,2-dihydropyridine-3-carbonitrile] 5a–c or bis[6-(2-aryl)-2-thioxo-1,2-dihydropyridine-3-carbonitrile] 6a,b, respectively. The reaction of compound 6a with each of 2-chloro-N-(4-bromophenyl) acetamide (7a), chloroacetamide (7b) in ethanolic sodium ethoxide solution at room temperature to give the corresponding 4,4′-(5-methyl-1-phenyl-1H-pyrazole-3,4-diyl)bis-6-(2-furyl)thieno[2,3-b]pyridine-2-carboxamide] derivatives 9a,b. While compound 6a reacted with hydrazine hydrate yielded the 4,4′-(5-methyl-1-phenyl-1H-pyrazole-3,4-diyl)bis[6-(2-furyl)-1H-pyrazolo[3,4-b]pyridin-3-amine] 11. The structures of the products were elucidated based on their spectral properties, elemental analyses and, wherever possible, by alternate synthesis. Antimicrobial evaluation of the products was carried out.     

2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑的合成研究

以2-氯苯并噻唑为原料,在N,N-二异丙基乙基胺存在下与D或L-苯甘氨醇反应后,不经分离直接与甲磺酰氯在N,N-二异丙基乙基胺作用下关环,一锅法合成了(R)或(S)-2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑,利用IR、~1HNMR、MS谱和旋光度对其结构进行了表征.通过优化研究2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑的合成工艺条件,可得到总收率为80%的(R)或(S)-2,3-二氢-2-苯基咪唑[2,1-b]苯并噻唑.     

Synthesis and characterization of quaternized poly-alkyl α-chloroacetoxymethacrylates

Summary The homopolymers of ethyl α-chloroacetoxymethacrylate (ECAM) and t-butyl α-chloroacetoxymethacrylate (TBCAM) were quaternized homogeneously with trimethylamine (TMA) and N,N-dimethyldodecylamine in N,N-dimethylformamide (DMF). The ¹H-NMR measurments were used for the determination of the degree of quaternization (DQ) values. The DQ value of poly-ECAM quaternized with TMA at room temperature after 1 h was found to be 84 %, while the DQ value for poly-ECAM quaternized with N,N-dimethyldodecylamine was 37 %. Reactivity of poly-TBCAM was lower than that of poly-ECAM. The lower DQ value of TMA quaternized poly-TBCAM (19 %) is caused by steric hindrance in the vicinity of - CH₂Cl group due to bulky t-butyl group. Increasing reaction time, polymer concentration and temperature above a certain value for each polymer, resulted in crosslinked polymers. Solubility of the quaternized polymers is controlled by the substituents. Thermogravimetric analysis showed distinct differences in thermal stabilities which is controlled by the quaternary amine groups and ester substituents. Received: 19 February 2000/Revised version: 14 April 2000/Accepted: 14 April 2000     

Studies on heterocyclic β-enaminonitriles: Synthesis of new condensed thieno[2,3-b]pyridines containing N-heterocyclic moieties

New versatile enaminonitrile-type building blocks, 3-aminothieno[2,3-b]pyridine-2-carbonitriles 3a,b, were synthesized from 3-cyanopyridine-2-(1H)-thiones 1a,b. Interaction of 3a,b with triethyl orthoformate furnished the corresponding ethoxymethylideneamino derivatives 6a,b. Derivatives of heterocyclic systems having the pyrazole, pyrimidine, and pyridine rings were obtained from the key precursors 3a,b and 6a, respectively.     

Hemicucurbit[n]urils and Their Derivatives – Synthesis and Applications

The first hemicucurbit[n]uril macrocycles were described in 2004, and since then a series of functionalised hemicucurbit[n]uril derivatives have been prepared and studied. The original hemicucurbit[n]urils suffer from sparse solubility, which limits their applications in supramolecular chemistry. Recent progress in the synthesis of a range of derivatives such as the biotin[n]urils, the bambus[n]urils, and the cyclohexylhemicucurbit[n]urils have enabled studies of the supramolecular chemistry of the hemicucurbituril system, both in water and in a range of organic solvents. In contrast to the popular cucurbit[n]uril macrocycles that are state-of-the-art hosts for cations, the hemicucbit[n]urils host anions. Herein we provide a survey of the literature covering the syntheses of the hemicucurbituril derivatives and their supramolecular chemistry.     

Synthesis and spark plasma sintering of the α-Si3N4 nanopowder

A two-step process (milling and then heat treatment) was used for the preparation of α-Si₃N₄ nanopowder. The influence of the milling time and heat treatment temperature as processing parameters were investigated on the formation of α-Si₃N₄. Silicon nitride ceramic was produced by spark plasma sintering at 1700 °C for 15 min, using MgSiN₂ additive. The optimum sample was produced in a 30 h milling time, heat treatment at 1300 °C, and a 22 °C/min heating rate conditions. X-ray fluorescence analysis showed that the purity of the final product is above 98%. Nanoindentation hardness and Young’s modulus of the SPS-ed sample were measured as 17±2.0 GPa and 290±11.0 GPa, respectively.     

First Synthesis of the α-L-Serine Linked Consensus Disaccharide of Neisseria gonorrhoeae and Neisseria meningitidis

The first total synthesis of the α-L -serine linked consensus disaccharide of Neisseria gonorrhoeae and Neisseria meningitidis was carried out in six linear steps, with 20.6 % overall yield.     

Dithieno[3,2-b:2′,3′-d]pyrrole-based materials: Synthesis and application to organic electronics

The application of dithieno[3,2-b:2′,3′-d]pyrroles (DTPs) in conjugated organic polymers has resulted in a variety of materials with reduced and low band gaps that exhibit high carrier mobilities, as well as enhanced solution and solid-state fluorescence. While DTP-based materials date back to the early 1990s, significant advances in the preparation and scope of these materials have been reported over the past decade. In this current report, we provide the first full review of DTP-based materials, highlighting in particular the recent advances made in the synthesis of both monomeric DTPs and their resulting materials, as well as the current progress of their application to various devices, including FETs, OPVs, OLEDs, and electrochromics.     

咪唑并[1,2-b]哒嗪的合成

咪唑并[1,2-b]哒嗪是第四代头孢类抗生素——头孢唑兰的3位侧链。以马来酸酐为起始原料,通过肼解、卤代、氨解、成环、脱卤合成了咪唑并[1,2-b]哒嗪。采用强酸为反应介质,可使马来酰肼的收率达到96%。采取一锅法合成中间体3,6-二氯哒嗪,产品收率由两步法的74.4%提高至88%。采用微波辅助合成3-氨基-6-氯哒嗪,反应时间从17 h缩短到0.5 h。在咪唑环形成过程中,以乙醇为溶剂,采用价格低廉的氯乙醛,简化了反应后处理过程。在6-氯咪唑并[1,2-b]哒嗪脱氯过程中,使用钯碳作催化剂,在常压下通入氢气即可完成反应。各单步收率均高于80%。