微波辅助高效合成N-(2,6-二硝基苯基)苯磺酰胺及其抑制种子萌芽活性的研究

本文通过微波辐射促进芳基亲核取代反应(S_NAr)获得20个N-(2,6-二硝基苯基)苯磺酰胺,该方法操作简单、收率高、耗时短(87%～94%,12min)、底物适用的范围广。种子萌芽实验结果表明,化合物3a在50、25μmol/L处理时可完全抑制大豆萌芽,在15μmol/L时抑制活性优于先导化合物PM1和ABA。该结果可为发现新型脱落酸功能类似物提供参考。     

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。      

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     

Highly Efficient Photodegradation of Organic Pollutants Assisted by Sonoluminescence

The mechanism of the photodegradation of azo dyes via ultrasonication is studied using a combination of the high‐performance liquid chromatography and UV–vis spectroscopy with detailed analysis of the kinetics. Based on the kinetics studies of the sonodegradation, it was proposed that the degradation of azo dyes was a multistage process that involved: (1) the direct attack of azo bonds and phenyl rings of dyes by the sonochemically formed reactive oxygen species; (2) the activation of semiconductor particles by the light emitted during cavitation and the triggering of the photocatalytic pathways of dye degradation and (3) increase of the adsorption capacity of the semiconductor particles due to the sonomechanically induced interparticle collisions. The detailed kinetics study can help in following an effective process up‐scaling. It was demonstrated that extremely short pulses of light flashes in a cavitated mixture activated the surface of photocatalysts and significantly enhanced dye degradation processes.     

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...     

Highly Efficient Synthesis of Tricyclic Perimidines under Microwave Heating

A new and efficient access to (Z)‐N‐(2‐argio‐1‐(1H‐perimidin‐2‐yl)vinyl)benzamide derivatives from readily available substrates in HOAc is described with aid of microwave irradiation. The results of our study provide a simple, straightforward synthetic route to these interesting classes of 2‐substituted perimidines analogs in excellent yields.     

Microwave Assisting Solid Phase Organic Reactions-Approach to the Efficient Solid Phase Organic Synthesis

Solid phase organic synthesis provides a rapid mean for the preparation of compounds libraries, and has been successfully used for the construction of both oligometric compounds and small molecule compounds libraries^[1]. That leads the resurgence of interest in solid phase organic synthesis, which encourages organic chemists to develop new reliable reactions, linkers and analytical techniques.     

A Two-Dimensional Semiconductive Metal-Organic Framework for Highly Efficient Microwave Absorption

Advanced microwave absorbing materials(MAMs)are urgently required to eliminate and attenuate microwaves to address the ubiq-uitous microwave radiations and inte...     

Organic Fluorophores Exhibiting Highly Efficient Photoluminescence in the Solid State

There has been extensive research on the development of organic optoelectronic devices, such as organic light‐emitting diodes, organic field‐effect transistors, and organic solid‐state lasers from various viewpoints, ranging from basic studies to practical applications. As organic materials are used as solids in these devices, the importance of organic chromophores that exhibit intense emissions of visible light in the solid state is greatly increasing in the field of organic electronics. However, highly efficient emission from organic solids is very difficult to attain because most organic emitting materials strongly tend to cause concentration quenching of the luminescence in the condensed phase. Therefore, in order to generate and improve organic optoelectronic devices, it is necessary to design novel chromophores that exhibit superior solid‐state emission performance. This Focus Review covers the recent development of highly emissive organic small molecules whose photoluminescence quantum yields in the solid state have been reported. Following the introduction, the photophysical processes of excited molecules are briefly reviewed. Subsequently, organic solid fluorophores are described with an emphasis on the characteristics of their molecular structures.     

Microwave‐Assisted Efficient Synthesis of Dihydropyrimidines in Solvent‐Free Condition

Abstract

An efficient synthesis of 3,4‐dihydropyrimidinones from an aldehyde, a ketoester, and a urea or thiourea using a catalytic amount of ferric chloride hexahydrate is described. Microwave irradiation has been used to accelerate the synthesis of the Biginelli compounds under solvent‐free conditions and in a short reaction time and with good yield.     

The Highly Efficient Synthesis of 1,2-Disubstituted Benzimidazoles Using Microwave Irradiation

The benzimidazole ring of the heterocyclic pharmacophores is one of the most widespread and studied systems in nature. The benzimidazole derivative synthesis study is a crucial point for the development of a clinically available benzimidazole-based drug. Here, we report a simple microwave assisted method for the synthesis of 1,2-disubstituted benzimidazoles. The combination of the molar ratio of N-phenyl-o-phenylenediamine:benzaldehyde (1:1) using microwave irradiation and only 1% mol of Er(OTf)₃ provides an efficient and environmental mild access to a diversity of benzimidazoles under solvent-free conditions. The proposed method allows for the obtainment of the desired products in a short time and with very high selectivity.     

微波促进1,3-偶极环加成反应合成氮杂糖苷衍生物

利用微波促进氮杂糖硝酮(2)与丙烯酸类衍生物(3)发生1,3-偶极环加成反应,立体选择性地得到了一系列新的含异噁唑烷的氮杂糖衍生物(4),反应效率显著提高,反应时间由95h缩短为5～15min,收率由67%提高到78%～88%.利用NMR和HRMS等方法结合化合物(4d-1)的单晶结构确定了产物的结构和相对构型.     

Microwave Assisted Efficient Synthesis and Crystal Structures of O-Hexadecalkylated Pyrogallol[4]arenes

Under microwave irradiation alkylation reactions of sixteen phenolic hydroxyl groups in tetra(p‐hydroxyphenyl)pyrogallol[4]arene with alkylating reagents such as n‐butyl iodide, benzyl chloride, and ethyl α‐chloroacetate were finished quickly in one step to give the fully O‐alkylated products. The X‐ray single crystal diffraction showed that the three peralkylated pyrogallol[4]arenes existed in rctt (cis‐trans‐trans) configuration.     

A General, Highly Efficient Ullmann C-O Coupling Reaction under Microwave Irradiation and the Effects of Water

A general, rapid and highly efficient method for the synthesis of diaryl ethers under the assistance of microwave irradiation was described. A series of diaryl ethers were prepared by direct coupling of phenols and aryl halides in good to excellent yields in anhydrous DMF or NMP at 150 ℃ within 20 rain. The presence of water was found to have a significant impact on the Ullmann C-O coupling reaction between aryl halides and phenols under microwave irradiation.     

Microwave Assisted Hydrothermal Way Towards Highly Crystalized N-Doped Carbon Quantum Dots and Their Oxygen Reduction Performance

We proposed a green microwave-assisted hydrothermal way to synthesize highly crystalized N-doped carbon quantum dots(N-CQDs).The N-CQDs obtained by this microwave method have good crystalline degree(ID/IG=0.6)and a high molar ratio of N/C(11.1%)comparing with those obtained from traditional top-down method.The experimental results show that glycerine plays a key role ill the fonnation of highly crystalized N-CQDs.The as-prepared N-CQDs have good luminescent property and may be utilized as fluorescent probe to detect ions or mark cells.As the majority of N atoms in the N-CQDs were pyridinic type(64.8%),the as-prepared N-CQDs were used as a catalyst for the oxygen reduction reaction(ORR)electrocatalysis in the anode of the fuel cell(the onset potential is-0.121V),which was a 4e-transfer procedure and the catalyst showed good stability after 100 cycles.     

Highly Efficient Cyanosilylation of Aldehydes and Ketones under Microwave,Solvent‐Free,and Lewis Acid–Free Conditions

The addition of TMSCN to aldehydes and ketones under microwave irradiation in the absence of any Lewis or Brønsted acid and solvent yielded the corresponding cyanohydrins in good yields in short reaction times (less than 30 min).     

微波辅助固相顶空-气相色谱法直接测定乙烯-醋酸乙烯共聚塑料中的苯乙酮

通过微波无溶剂提取与顶空气相色谱在线联用,建立了一种可直接快速检测固体样品中挥发性成分苯乙酮的方法,考察了微波加热时间对灵敏度和重现性的影响.苯乙酮峰面积随微波加热时间的延长呈现先增加后减小的趋势,短时间微波辐射下苯乙酮峰面积的重现性优于长时间微波辐射.本方法的线性范围为0.003～0.333 mg/g;检出限为2.022 μg/g.与常规加热的顶空气相色谱法相比,本方法简便、省时、重现性好.对苯乙酮与共存物峰面积比随时间变化的研究结果表明,短时间微波加热有利于实现极性组分的选择性提取.     

Efficient Acylation and One-Pot Synthesis of Dehydroandrographolide Succinate on a Large Scale Assisted with Microwave Radiation

A rapid and convenient method for acylation and large-scale synthesis of dehydroandrographolide succinate has been developed under microwave irradiation. It is a one-pot condensation and is compatible with dehydration and rearrangement of double bond in mild reaction conditions with good yield, high purity (up to 99.8%), time-savings, few pollutants and low cost. In addition, a number of acylation derivatives were synthesized under microwave irradiation.     

Microwave Assisted,Solvent Free One Pot Synthesis of Nitriles from Aryl Aldehydes on Melamin Formaldehyde as Solid Support

Various aryl aldehydes underwent prompt one pot conversion into the corresponding nitriles in high yields by reacting with hydroxylamine hydrochloride supported on melamine formaldehyde under microwave irradiation in the presence of ammonium acetate as catalyst.     

Simple and Highly Efficient Procedure for Conversion of Aldoximes to Nitriles Using N-(p-Toluenesulfonyl) Imidazole

A facile and efficient method for dehydration of aldoximes into nitriles using N-(p-toluenesulfonyl) imidazole (TsIm) is described. In this method, aldoximes were refluxed with TsIm in the presence of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU) in dimethylformamide (DMF) to afford the corresponding nitriles in good yields. This methodology is highly efficient for various structurally diverse aldoximes including aromatic, heteroaromatic, and aliphatic oximes. A plausible mechanism for the conversion of aldoxime into nitriles using TsIm/DBU is explained.