含氯荧光素的合成

以2,4-二羟基苯甲酸甲酯为原料,经过氯代反应、水解反应、脱羧反应合成2,4-二氯间苯二酚.在甲基磺酸作用下,以2,4-二氯间苯二酚和3,6-二氯-4-羧基邻苯二甲酸酐为原料缩合得到重要的含氯荧光素.目标产物及中间体的结构通过IR、1HNMR、MS和元素分析表征.     

微波辐射促进合成系列7-二乙氨基类香豆素及其荧光性质的研究

本文采用微波辐射技术合成了系列7-二乙氨基类香豆素,并通过红外光谱、核磁共振谱进行了结构表征。测试了所合成化合物的吸收光谱和发射光谱,研究了不同溶剂对荧光性能的影响。结果表明:与传统合成方法相比,该方法具有反应时间短、产率高等优点。且所合成的化合物随着溶剂极性的增大均表现为正溶剂化显色,且斯托克斯位移较大。     

微波辐射合成香豆素的研究

以水杨醛和乙酐为原料 ,乙酸钠为催化剂 ,在微波辐射下合成香豆素。当摩尔比为水杨醛∶乙酐∶乙酸钠 =1∶ 3.6∶ 0 .2 5时 ,采用 480 W微波辐射 10 min,香豆素产率可达 90 %。与传统合成法相比 ,该法具有反应时间短、产率高等优点     

微波辐射合成对乙酰氨基酚的研究

以对氨基苯酚和乙酸酐为原料,以锌粉为抗氧化剂,以活性炭为脱色剂,以稀乙酸为反应介质,采用微波辐射技术合成对乙酰氨基酚。探索了不同反应条件对产率的影响。实验表明,当n(对氨基酚)∶n(乙酸酐)为1∶1.3,反应介质稀乙酸体积浓度为4%,微波辐射功率为500 W,反应时间为17 m in,反应温度为105℃时,产率可达82.1%。     

微波辐射合成柠檬酸三乙酯

采用微波辐射法在强酸性阳离子交换树脂催化下,由柠檬酸和乙醇合成得到了柠檬酸三乙酯。主要考察了微波加热时间、催化剂用量等对产率的影响。结果表明,收率达90．6％的合成工艺条件为：微波功率为225W,加热时间约40min,催化剂用量约2％。常规法合成柠檬酸三乙酯需要在醇溶液中长时间加热制备,与常规方法相比,该法反应速度提高约12倍。     

微波辐射下合成月桂酸乙酯

以月桂酸和乙醇为原料,对甲苯磺酸为催化剂,运用微波技术合成果香型香料月桂酸乙酯.其较佳合成条件:醇酸摩尔比2.0:1,辐射时间40min,辐射功率30%、560W,催化剂用量为月桂酸的0.20%(质量分数),产率可达98.0%以上.与常规加热法相比,具有反应时间短、节约能源、操作简便、产率高等优点.     

几种含羧基的不对称卟啉化合物的微波合成及其光谱性质

羧基苯基卟啉是一种重要的水溶性卟啉化合物,在分析化学、仿生化学等领域具有潜在应用价值。利用微波加热法,以4-甲酰基苯甲酸、吡咯及对位R取代苯甲醛(R=H、Cl、OCH3)为原料分别合成了3种含羧基的不对称卟啉化合物。微波辐射时间8～10 min,产物收率分别为5%、5.8%、2.8%。目标化合物结构分别经UV-Vis、IR、1HNMR表征,并讨论了取代基结构及其电子效应对光谱性质的影响。     

微波辐射合成秦皮乙素的研究

以无水氯化锌为催化剂,采用微波辐射,由1,2,4-苯三酚与丙炔酸乙酯发生环化反应制备秦皮乙素。结果表明,微波辐射合成秦皮乙素的最佳反应条件为∶n(1,2,4-苯三酚)∶n(丙炔酸乙酯)=1.0∶1.0,3.5 g氯化锌,反应时间10 min,反应温度105℃,微波功率400 W,产率可达87.4%。     

微波辐射合成香豆素的研究

以水杨醛和乙酐为原料,乙酸钠为催化剂,在微波辐射下合成香豆素。当摩尔比为水杨醛：乙酐：乙酸钠＝1：3.6:0.25时,采用480W微波辐射10min,香豆素产率可达90％。与传统合成法相比,该法具有反应时间短、产率高等优点。     

微波辐射合成肉桂酸

本文简单介绍了微波有机化学反应对化学反应的作用原理和微波反应制取肉桂酸的实验过程。     

微波辐射辅助合成4-甲基香豆素衍生物

以硫酸氢铵(物质的量分数为0.12)为催化剂,在微波辐射下,取代酚与乙酰乙酸乙酯(物质的量比为1∶1.5)于无溶剂条件下通过Pechmann缩合反应,合成了4个4-甲基香豆素衍生物,微波输出功率800W,反应时间10min,产率45%～88.4%,反应时间短,操作简便有效。     

微波辅助3-甲酰氨基吡唑4-羰酸衍生物的合成

利用微波辅助技术,以3-氨基吡唑4-甲酰胺、3-氨基吡唑-4-甲酸乙酯为原料合成新型吡唑化合物--3-甲酰氨基吡唑-4-甲酰胺、3-甲酰氨基吡唑-4-甲酸乙酯,系统的研究了反应时间、反应温度、原料配比以及催化剂用量对反应的影响,确定该反应的最优化反应条件:3-氨基吡唑4-羰基取代化合物与甲酰胺的比例1:4,催化剂用量为...     

微波辅助下5-碘尿嘧啶衍生物的快速合成

在微波辐射下,I2在稀硝酸水溶液中快速在尿嘧啶5位发生碘化反应,以较高产率得到了9个5-碘嘧啶衍生物(75%~90%)。产物结构经1HNMR和13CNMR确证。     

Microwave-assisted solvent-free synthesis and spectral properties of some dimethine cyanine dyes as fluorescent dyes for DNA detection

A series of dimethine cyanine dyes were synthesized in a fast, efficient and high yield by the condensation of quaternary salts with 1H-indole-3-carbaldehyde in the presence of piperidine under solvent-free microwave irradiation. The products were identified by ¹H NMR, IR, UV–vis spectroscopy and elemental analysis. The absorption and fluorescence properties of the dyes in both the free state and DNA or BSA were investigated. Significant enhancement of the fluorescent quantum yield was observed for all the dyes in the presence of DNA, with one compound demonstrating excellent sensitivity as a fluorescent probe.     

The synthesis and spectral properties of novel phthalocyanines with pendant bulky units

Novel phthalocyanines with biphenyl substituents and ester groups that are readily soluble in organic solvents were synthesized from a phthalonitrile derivative obtained by displacement of the –CH proton in 1-chloro-3,4-dicyano-6-(1,1-dicarbethoxymethyl)benzene with 4-(chloromethyl)biphenyl, followed by cyclotetramerization in the presence of metal salts {CuCl₂, Pb(CH₃COO)₂·3H₂O, CoCl₂ and Zn(CH₃COO)₂}. Transesterification of malonyl esters occurred during the cyclotetramerization of dinitrile with CuCl₂, Pb(CH₃COO)₂·3H₂O in 1-pentanol in the presence of DBU. The structures of the newly synthesized molecules were verified using elemental analysis, ¹H NMR, FT-IR, MicroTOF mass and UV–vis spectral data.     

Monomethine cyanine dyes with an indole nucleus: Microwave-assisted solvent-free synthesis,spectral properties and theoretical studies

Four asymmetric monomethine indocyanine dyes were rapidly synthesized by the condensation of indole quaternary salts with 2-methylthio quinoline quaternary salt in the presence of triethylamine under solvent-free, microwave irradiation. The effects of microwave power and irradiation time on yield were examined. The products were identified using elemental analysis, IR, MS, UV–Vis spectra, ¹H and ¹³C NMR. The absorption of the dyes was investigated both experimentally and theoretically. Calculations performed using a combination of the time-dependent density functional theory (TD-DFT) and the polarizable continuum model (PCM) reproduced the π → π¹ type absorption bands of the dyes. Multiple linear regression, applied to the theoretical absorption maxima in different solvents, fitted well with experimental data. Resonance frequency calculations were undertaken to study the IR spectra of the dyes and the calculated results were in good accordance with experimental values.     

Microwave-assisted one-pot synthesis of 2-nitroalkylidene-1,3-oxathiolane derivatives

A simple and efficient route for the synthesis of 1,3-oxathiolanes containing highly polarized C–C double bonds is reported. Anionic adduct derived from nitromethane and carbon disulfide attacks on oxiranes regioselectively using Et₃N under microwave irradiation. This protocol has the advantages of short reaction time, solvent-free conditions, and easy workup procedure.     

The synthesis and two-photon excited fluorescence properties of novel branched fluorene derivatives

Two novel, V-shaped fluorene derivatives branched from triphenylamine and their linear analogue were synthesized via Cu-mediated Ullmann condensation and subsequent Pd-catalyzed Heck coupling reaction. Their two-photon excited fluorescence properties as well as their linear absorption and single-photon excited fluorescence properties were examined. When excited at 730 nm by a Ti:sapphire femtosecond laser, the compounds exhibited strong two-photon excited blue fluorescence. The two-photon excited fluorescence cross-sections of V-shaped derivatives in toluene at 730 nm were ∼506 GM in the case of N, N-bis{7-[4′-(N, N-diphenylamino)styryl]-9,9-diethyl-9H-fluorene-2-yl}-aniline) and 397 GM for N, N-Bis{7-[4′-(N, N-diphenylamino)styryl]-9,9-diethyl-9H-fluorene-2-yl}-4-acetyl-aniline), respectively.     

The synthesis and two-photon excited fluorescence properties of novel branched fluorene derivatives

Two novel, V-shaped fluorene derivatives branched from triphenylamine and their linear analogue were synthesized via Cu-mediated Ullmann condensation and subsequent Pd-catalyzed Heck coupling reaction. Their two-photon excited fluorescence properties as well as their linear absorption and single-photon excited fluorescence properties were examined. When excited at 730 nm by a Ti:sapphire femtosecond laser, the compounds exhibited strong two-photon excited blue fluorescence. The two-photon excited fluorescence cross-sections of V-shaped derivatives in toluene at 730 nm were 506 GM in the case of N, N-bis{7-[4′-(N, N-diphenylamino)styryl]-9,9-diethyl-9H-fluorene-2-yl}-aniline) and 397 GM for N, N-Bis{7-[4′-(N, N-diphenylamino)styryl]-9,9-diethyl-9H-fluorene-2-yl}-4-acetyl-aniline), respectively.