Microwave Assisted Synthesis of Dibenzoxazepines

Dibenzo[b,f][1,4]oxazepine derivatives were synthesized in good yields and short reaction times by the reaction of 2‐chlorobenzaldehydes and 2‐aminophenoles in basic conditions under microwave irradiation.     

Microwave Assisted Synthesis of Pyridone Derivatives

A series of pyridone derivatives were synthesized by the reaction of aromatic aldehydes, 1,3‐dicarbonyl compounds and ammonium acetate under microwave irradiation in the absence of solvent. The reactions were completed within 3‐5 min to give the desired products in 72.4‐86.2% yields.     

Microwave Assisted Synthesis of Chitosan Nanoparticles

Chitosan nanoparticles (CHN) were prepared based on ionotropic gelation between low moleculer weight chitosan and sodium tripolyphosphate (TPP) under microwave irradiation. Particle size, zeta potential, and FT-IR techniques were used for characterization of CHN. The influence of reaction time on the nanoparticle size distribution was investigated, and the results showed that the microwave irradiation method evidently decreases the reaction times and particle size over the conventional method. It was determined by the results of the zeta potential measurements that synthesized CHN under microwave irradiation clearly exhibits more homogeneous and stable dispersion.     

Microwave Assisted Neat Synthesis of Spiropyrrolidine Library

A new class of functionalized nitrothiophene containing spirropyrrolidines has been synthesized with high regioselectivity in moderate to excellent yields via microwave assisted solvent‐free‐three component 1,3‐dipolar cycloaddition reaction of in situ generated azomethineylides with various substituted chalcones as dipolarophiles. The structures of the newly synthesized compounds were established by analytical and spectral analysis. The product yields were slightly improved and reaction times were reduced to a great extent under microwave condition.     

微波辅助“一锅煮”合成香豆素3-羧酸类化合物

以取代水杨醛和丙二酸二乙酯为原料,乙醇为溶剂,以吡咯为碱于140 ℃微波反应20 min,再加入氢氧化钠于120 ℃微波反应10 min,采用“一锅煮”的方法合成了8个香豆素-3-羧酸类化合物,收率可达84.0%~96.6%。本方法具有反应时间短、产率高、操作简便的优点,为香豆素-3-羧酸类化合物提供了一种高效、便捷的实验室合成方法。     

微波辅助RGD环肽的固相合成

以2-氯代三苯甲基氯树脂为载体，采用Fmoc/t-Bu/Dmab正交保护策略，在微波辅助下合成了环肽c(fKRGD)，收率22.5%，纯度94.5%，其结构经MS(ESI), MS(MALDI-TOF)和HPLC确证。     

微波辅助合成发光可调ZnS∶Cu纳米晶

以巯基丙酸(MPA)为稳定剂, 利用微波辐射加热方法制备了水溶性的Cu掺杂的ZnS纳米晶. 通过改变微波条件, 可以在460～572 nm之间实现对ZnS∶Cu纳米晶发射峰位的连续调控. 通过XRD、 UV-Vis、荧光及荧光衰减对ZnS∶Cu纳米晶的结构和发光性质进行了详细探索, 并利用时间分辨荧光光谱对其发光机理进行了初步研究.     

微波固相反应制备CdS纳米粒子

硫化镉是一种重要的半导体材料,在太阳能转化、非线形光学、光电子化学电池和光催化方面具有广泛的应用[1,2]。近十年以来,人们已经使用了许多的方法来制备纳米硫化镉[3~7]。由于微波能同时促进吸热反应和放热反应,对化学反应具有催化作用,可降低反应的温度,从而为化学反应创造     

Microwave Assisted Synthesis and Antimicrobial Activity of Novel Pyrrolidine Derivatives

Microwave assisted synthesis of 1-acetyl-2-benzylpyrrolidine-2-carboxylic acid and its derivatives has been developed with highly encouraging yields. 2-Benzyl-tert-butylpyrrolidine-1,2-dicarboxylate is used as an initial compound in the four steps synthesis of the target compounds. Structures of the products 5a–5h have been confirmed by spectroscopic methods. According to antimicrobial tests 1-acetyl-2-benzylpyrrolidine-2-carboxamide 5c is determined to be the most potent product.     

微波辅助合成N-（2-嘧啶基）吲哚化合物

以取代吲哚和2-氯嘧啶为原料,通过微波辅助合成N-（2-嘧啶基）吲哚化合物,对碱、溶剂、反应温度、反应时间、微波功率等进行了优化,筛选得到的最佳反应条件为：以碳酸铯为碱,DMSO为溶剂,于微波功率500 W、145℃下反应5min。在最佳反应条件下,3个4-位取代吲哚化合物均可与2-氯嘧啶反应,收率大于80%,产物结构经¹H NMR和¹³C NMR确证。      

化妆品中Hg、As和Pb的微波消解—氢化物发生ICP—AES法测定

采用微波消解－氢化物发生ICP－AES法测定化妆品中Hg、As和Pb,加入L－半胱氨酸消除了过渡金属离子的干扰,考察了微波消解、氢化物发生的最佳条件。建立的方法简便快速,测定Hg、As和Pb的RSD分别为0．59％、1．2％、2．4％（n=10),样品加标回收率分别为98．5％、99．3％和100．1％。该法已应用于化妆品的常规测定,得到满意的结果。     

Microwave Assisted Synthesis of Diosgenin Esters of Maleic and Itaconic Acids

Diosgenin monomaleate and diosgenin monoitaconate were prepared by the esterification of diosgenin with maleic and itaconic anhydride, respectively, in toluene using p-toluenesulphonic acid as catalyst. A domestic microwave oven was modified and used for the synthesis of both products. The reaction time for consuming all the diosgenin according to thin-layer chromatography (TLC) was reduced by around 90% in the synthesis of monomaleate of diosgenin as well as in the synthesis of monoitaconate of diosgenin in comparison with conventional heating, whereas the monomaleate of diosgenin yield increased from 43 to 80–85% and the monoitaconate of diosgenin yield from 34 to 95% under the same experimental conditions. It was easier to purify the diosgenin monoitaconate than the diosgenin monomaleate. Both products were characterized by NMR and FTIR spectroscopy.     

微波法合成乙二醇插层镍铝层状双金属氢氧化物

乙二醇(EG)插层层状双金属氢氧化物(LDH)可作为层间催化反应器,用于原油中环烷酸与EG的酯化脱酸反应,但其合成过程需要较长时间。 以硝酸根型镍铝LDH为前体,在KOH促进下,采用微波辅助的离子交换法合成EG插层LDH,省时节能,提高效率。 考察了微波时间、微波温度和微波功率对EG插层LDH结构的影响。 并用XRD、FT-IR和TG-DSC等比较了微波法和常规方法合成的EG插层LDH的性质。 结果表明,微波辐射能提供高能量,促进待交换阴离子向层间的扩散,并减弱层板与层间原有阴离子间的作用力,在微波温度为120 ℃,微波时间为10 min和微波功率550 W的条件下,即可得到结晶度高的EG插层LDH。 微波法合成的EG插层LDH与常规方法合成的具有相似的性质和更高的结晶度,而合成时间可由12 h大幅缩短至10 min。     

An Efficient Microwave Assisted Synthesis and Antimicrobial Activty of 1,2,3-Triazolyl-pyrrolidinyl-quinolinolines

Russian Journal of General Chemistry - A novel series of 1,2,3-triazolyl-pyrrolidinyl-quinolinolines are synthesised by the Click reaction of alkynes with aromatic azides catalysed by CuI under...     

微波促进立体选择性合成烯丙酸酯类高碳糖衍生物

在微波促进下, 利用酮糖(1)及糖酸内酯(4)与叶立德(2, Ph₃PCHCOOEt)的Wittig反应, 立体选择性地合成了糖基烯丙酸酯类化合物(3和5), 反应效率显著提高, 反应时间由原来的20 h缩短为10 min; 并且研究了不同反应溶剂对反应立体选择性的影响. 提供了一种高效、 简便合成含有烯丙酸酯类高碳糖衍生物的方法.     

CTAB辅助微波水热合成花簇状SnS微球

以氯化亚锡(SnCl2.2H2O)和硫代乙酰胺(TAA)为前驱物,十六烷基三甲基溴化铵(CTAB)为表面活性剂,采用微波水热法控制合成花簇状SnS微球。采用XRD和FESEM等分析手段对制备的样品进行表征。结果表明:合成的产物为正交晶系的SnS微晶,且结晶性良好;SnS微晶是由长方形纳米片自组装而成的花簇状微球。通过改变CTAB用量,可以实现花簇状SnS微晶的形貌和尺寸的调控,并初步分析了其形成过程。利用紫外-可见吸收光谱分析,产物的光学带隙约为1.51 eV;室温光致发光光谱表明,产物在832 nm处具有近红外发光特性。     

Cyanuric Acid and Cyanurates

A review of studies concerned with an interesting group of compounds of cyanuric acid, which is an intermediate between inorganic and organic compounds, is given. A first attempt is made to generalize and systematize all the known compounds of this acid. The syntheses, IR studies, thermal decomposition, and the mechanism of thermal conversion of the cyanuric acid salts are considered. This review may prove of interest for the researchers working in different fields, chemical engineers, students, post-graduates, and teachers of higher schools.     

Microwave Assisted Preparation of Isatins and Synthesis of (±)-Convolutamydine-A

Microwave assisted preparation of a number of isatin derivatives is reported. A simple synthesis of (±)-convolutamydine-A, a potent compound against leukemia cells, is presented.