微波促进下9-芳基氢化吖啶-1,8-二酮的合成研究

本文研究了微波促进下芳香醛、5,5-二甲基-1,3-环己二酮与碳酸氢铵的三组分无溶剂缩合反应,并通过该反应合成了一系列9-芳基氢化吖啶-1,8-二酮类化合物.这一合成方法具有操作简便、反应条件温和、产率高、对环境友好等特点.     

离子液体中5,5-二甲基-1,3-环己二酮与N-芳亚甲基芳胺反应合成 吖啶衍生物

在离子液体[bmim]Br中, 5,5-二甲基-1,3-环己二酮与N-芳亚甲基芳胺反应合成了一系列四氢吖啶-1,8-二酮衍生物, 该反应具有适应性广、产率高、污染少、环境友好等优点.     

L-脯氨酸催化合成1,4-二氢吡啶和1,8-二氧代十氢吖啶

含1,4-二氢吡啶和1,8-二氧代十氢吖啶分子片段的化合物具有扩张血管、抗菌和抗肿瘤等药理活性，因此，探讨和优化该类衍生物绿色合成方法成为药物合成领域的热点之一。基于有机小分子催化剂L-脯氨酸廉价易得、无毒无害和水溶性等特点，结合微波辐射技术快速高效等优势，以芳香醛、β-二酮 (乙酰乙酸乙酯/二甲基环己二酮)和乙酸铵为原料，乙醇为溶剂，催化剂用量20 mol/mol，微波功率300 W和80℃的条件下，通过成环缩合反应“一锅法”合成了目标化合物，收率达80%～93%。该方法具有条件温和、操作简单以及环境友好等优点。      

超声辅助多组分反应:水介质中以β-环糊精为可重复使用的超分子催化剂绿色合成氮取代的1,8-二氧-十氢吖啶

以可生物降解和可重复使用的β-环糊精为超分子催化剂,在水介质中采用简易方法合成了氮取代的1,8-二氧-十氢吖啶,所得产物的收率很高,选择性也为中等到较高.该过程为双甲酮、芳香醛和芳香胺三组分通过串联Michael加成反应一步合成得到产物.本文提供了一个高效且环境友好的合成氮取代的1,8-二氧-十氢吖啶的新方法.     

超声辅助多组分反应:水介质中以β-环糊精为可重复使用的超分子催化剂绿色合成氮取代的1,8-二氧-十氢吖啶（英文）

以可生物降解和可重复使用的β-环糊精为超分子催化剂,在水介质中采用简易方法合成了氮取代的1,8-二氧-十氢吖啶,所得产物的收率很高,选择性也为中等到较高.该过程为双甲酮、芳香醛和芳香胺三组分通过串联Michael加成反应一步合成得到产物.本文提供了一个高效且环境友好的合成氮取代的1,8-二氧-十氢吖啶的新方法.     

水相回流条件下N-取代吖啶二酮衍生物的合成

在水相回流条件下,以芳香醛、5,5-二甲基-1,3-环己二酮（达米酮）和苯胺/对甲苯胺为原料,经过多组分一锅反应,合成了一系列N-取代吖啶二酮衍生物,收率在69%~90%之间。 该过程以水作为溶剂,无有机溶剂污染,而且操作简单,后处理方便。     

微波辐射下一步合成9-芳基-1,2,3,4,5,6,7,8,9,10-十氢-1,8-吖啶二酮

以芳醛、1,3-环己二酮、醋酸铵为原料在无溶剂条件下经微波辐射合成了一系列9-芳基-1,2,3,4,5,6,7,8,9,10-十 氢-1,8-吖啶二酮. 该反应的反应时间短、产率高、环境友好、后处理方便. 产物的结构经红外光谱、核磁共振谱表征, 3d的结构经单晶X射线衍射进一步确证.     

3,6-二甲基-9-芳基-2,7-二氧杂-1,2,7,8,9,10-六氢-1,8-吖啶二酮衍生物的一步合成

以芳醛、6-甲基-4-羟基-2-吡喃酮、醋酸铵为原料, 醋酸为溶剂, 一步合成了一系列3,6-二甲基-9-芳基-2,7-二氧 杂-1,2,7,8,9,10-六氢-1,8-吖啶二酮, 产物的结构经红外、核磁、元素分析进行了表征, 并对反应过程提出了可能的机理.     

新型席夫碱锆路易斯酸催化1,4-二氢吡啶和多氢喹啉高效合成

合成了一种新型对空气稳定的β-萘酚醛席夫碱锆全氟辛基磺酸盐路易斯酸催化剂.该催化剂由β-萘酚醛席夫碱锆二氯化物与全氟辛基磺酸银在室温下避光反应制得.催化活性实验表明,在80℃和无溶剂条件下,该催化剂(5mol%)能够高效催化醛、β-酮酯和醋酸铵的Hantzsch反应制备1,4-二氢吡啶化合物;也可以高效催化芳香醛、环状β-二酮、β-酮酯和醋酸铵的反应制备4-芳基多氢喹啉化合物.催化剂在重复使用五次之后,产率没有明显降低,为1,4-二氢吡啶和4-芳基多氢喹啉化合物的制备提供了一条简单有效的途径.     

无催化剂、水相合成5,5-(苯基亚甲基)双(2,2-亚丁基-1,3-二噁烷-4,6-二酮)衍生物

以芳香醛和2,2-亚丁基-1,3-二噁烷-4,6-二酮为原料,以水为反应介质,无需外加催化剂,通过Knoevenagel缩合与Michael加成的串联反应简单有效地合成了5,5-(苯基亚甲基)双(2,2-亚丁基-1,3-二噁烷-4,6-二酮)衍生物.一系列取代芳香醛被考察,发现该反应具有收率高(63%~83%)、反应温和、操作简单及环境友好等优点.     

可膨胀石墨催化合成3,3,6,6-四甲基-9-芳基-1,2,3,4,5,6,7,8-八氢化氧杂蒽-1,8-二酮

在可膨胀石墨催化下, 由芳香醛和5,5-二甲基-1,3-环己二酮缩合制备了3,3,6,6-四甲基-9-芳基-1,2,3,4,5,6,7,8-八氢化氧杂蒽-1,8-二酮. 在乙醇-水介质中回流反应2.5 h, 反应产率可达87%～93%. 该方法不仅反应时间短, 产率高, 而且催化剂价廉易得、对环境友好, 催化剂经简单过滤后可重复使用.     

Thermally stable polymers based on 1,3,4-oxadiazole rings

<正>In the present work,new thermally stable polymers containing 1,3,4-oxadiazole units have been synthesized through Huisgen reaction of the aromatic bis-tetrazole compounds with the aromatic/aliphatic bis-acid chlorides in pyridine as solvent.The obtained polymers are insoluble or slightly soluble in polar aprotic solvents such as DMSO and DMF. Thermal analyses of the polymers using DSC and TGA techniques showed that the polymers had improved thermal stabilities.The model reaction was also investigated and the resulting bis-l,3,4-oxadiazole compounds were characterized by conventional spectroscopic methods.     

芳基咪唑并[4,5-f][1,10]菲咯啉的无溶剂绿色合成研究

以菲咯啉二酮、苯甲醛及其衍生物和醋酸铵为原料,采用无溶剂绿色研磨工艺,合成了芳基咪唑并菲咯啉化合物.通过对不同反应条件的筛选,得到一条高效、简便、绿色的合成芳基咪唑并菲咯啉化合物路线,不同的芳醛与菲咯啉二酮都可以较高的收率得到相应的芳基咪唑并[4,5-f][1,10]菲咯啉.     

Silver‐Catalyzed Arylation of (Hetero)arenes by Oxidative Decarboxylation of Aromatic Carboxylic Acids

A long‐standing challenge in Minisci reactions is achieving the arylation of heteroarenes by oxidative decarboxylation of aromatic carboxylic acids. To address this challenge, the silver‐catalyzed intermolecular Minisci reaction of aromatic carboxylic acids was developed. With an inexpensive silver salt as a catalyst, this new reaction enables a variety of aromatic carboxylic acids to undergo decarboxylative coupling with electron‐deficient arenes or heteroarenes regardless of the position of the substituents on the aromatic carboxylic acid, thus eliminating the need for ortho‐substituted aromatic carboxylic acids, which were a limitation of previously reported methods.     

Polycondensation of benzyl chloride over Ga- and In-modified ZSM-5 type zeolites and Si-MCM-41 or Montmorillonite-K10 supported GaCl3 and InCl3 catalysts

Performance of In- and Ga-modified ZSM-5 type zeolites (namely, In₂O₃/H-ZSM-5, Ga₂O₃/H-ZSM-5, H-GaMFI and H-GaAlMFI) and InCl₃ or GaCl₃ supported on high silica mesoporous MCM-41 or on Mont.-K10 in the liquid phase polycondensation of benzyl chloride to polybenzyl has been investigated. Influence of solvent (namely, dichloroethane, n-heptane and ethanol) and temperature on the rate of polycondensation of benzyl chloride over the catalyst (InCl₃/Si-MCM-41) showing highest polycondensation activity has also been studied. The In- and Ga-containing solid catalysts show good or high activity in the polycondensation reaction at the reaction condition normally employed in the benzylation of aromatic compounds by benzyl chloride. However, the polycondensation is strongly influenced by the solubility of the polybenzyl polymer in the reaction medium and consequently by the solvent used as the reaction medium.     

New approach for the synthesis of 1-aryl- and 1-heteroaryl-5-nitrouracil derivatives

1-(2,4-Dinitrophenyl)-5-nitrouracil and its 3-methyl derivatives were synthesized and used as substrates in reaction with aromatic amines and amino pyridines. In the reaction of aniline with 1-(2,4-dinitrophenyl)-5-nitrouracil, only the acyclic adduct was isolated. When 1-(2,4-dinitrophenyl)-3-methyl-5-nitrouracil was treated with aniline and other aromatic amines or amino pyridines, the desired 1-aryl-5-nitrouracil derivatives were obtained in satisfactory yield. The influence of the free H-3 proton present in the uracil ring on the course of the reaction is discussed.     

Front Cover: Facile Multicomponent Synthesis of Oxazolidinones from Primary Amines and Cesium (Hydrogen)Carbonate (Eur. J. Org. Chem. 27/2023)

A facile multicomponent, catalyst-free oxazolidinone synthesis from primary aliphatic or aromatic amines, dibromoethane (DBE), and the usage of either cesium carbonate or cesium hydrogencarbonate as the simultaneous base and C1 source is reported. The applicability of this technically simple reaction was demonstrated by a broad scope with generally high yields, enabling concise late-stage functionalization of amino groups into N-substituted oxazolidinones. The proposed operating reaction mechanism consists of a first-step nucleophilic substitution reaction between DBE and the primary amine, followed by the formation of a carbamate or carbonate intermediate and subsequent cyclization. Additional versatility of the herein-developed protocol has been showcased in a medicinal chemistry approach by the generation of an oxazolidinone-modified dipeptidyl peptidase 8 (DPP8) inhibitor.     

离子液体[2-aemim]im催化Knoevenagel反应和异噁唑酮合成

以碱性离子液体1-(2-氨基乙基)-3-甲基咪唑咪唑盐([2-aemim]im)作为催化剂,催化Knoevenagel反应和4-芳亚甲基异噁唑-5(4H)-酮衍生物的合成。实验结果表明:在无溶剂条件下,该离子液体对Knoevenagel反应具有很高的催化活性,一系列芳香醛和活泼亚甲基化合物的反应在室温条件下2 min内顺利完成,均以90%以上的高产率生成取代烯烃产物.将该碱性离子液体用于催化乙酰乙酸乙酯或苯甲酰乙酸乙酯、盐酸羟胺和芳香醛三组分一锅法缩合制备4-芳亚甲基异噁唑-5(4H)-酮衍生物,具有反应时间较短、产率较高和后处理简单的特点。离子液体经简单处理后能多次循环使用。     

Numerical Investigation on 1,3-Butadiene/Propyne Co-pyrolysis and Insight into Synergistic Effect on Aromatic Hydrocarbon Formation

A numerical investigation on the co-pyrolysis of 1,3-butadiene and propyne is performed to explore the synergistic effect between fuel components on aromatic hydrocarbon formation.A detailed kinetic model of 1,3-butadiene/propyne co-pyrolysis with the sub-mechanism of aromatic hydrocarbon formation is developed and validated on previous 1,3-butadiene and propyne pyrolysis experiments.The model is able to reproduce both the single component pyrolysis and the co-pyrolysis experiments,as well as the synergistic effect between 1,3-butadiene and propyne on the formation of a series of aromatic hydrocarbons.Based on the rate of production and sensitivity analyses,key reaction pathways in the fuel decomposition and aromatic hydrocarbon formation processes are revealed and insight into the synergistic effect on aromatic hydrocarbon formation is also achieved.The synergistic effect results from the interaction between 1,3-butadiene and propyne.The easily happened chain initiation in the 1,3-butadiene decomposition provides an abundant radical pool for propyne to undergo the H-atom abstraction and produce propargyl radical which plays key roles in the formation of aromatic hydrocarbons.Besides,the 1,3-butadiene/propyne co-pyrolysis includes high concentration levels of C3 and C4 precursors simultaneously,which stimulates the formation of key aromatic hydrocarbons such as toluene and naphthalene.     

对苯二甲醛或间苯二甲醛与5，5-二甲基-1，3-环己二酮的反应：含有双4（日）-吡喃、1，4-二氢吡啶结构单元的杂环化合物的合成

用对苯二甲醛或间苯二甲醛与5，5-二甲基-1，3-环己二酮反应，在不同条件下得到了含有双4(H）-吡喃、1，4_二氢吡啶结构单元的双一氧杂蒽衍生物、双-吖啶衍生物、以及双-AL羟基吖啶衍生物．