一锅法合成3-芳基-1，5-双（2-羟基芳基）-戊二酮-1，5

2-羟基苯乙酮、芳醛、氢氧化钾“一锅”反应合成了3-芳基-1，5-双（2-羟基芳基）-戊二酮-1，5。     

一锅法合成2-羟基-9-芴酮类化合物

芴酮骨架的构建对于相关天然产物合成、药物分子结构修饰以及光电材料开发等具有重要意义。以苯环作为桥连基团,将呋喃环及炔酮片段构建在同一个分子内,设计并合成了邻呋喃芳基炔酮底物(1a)。利用化合物1a分子内呋喃环与炔键的D-A反应,在酸性条件下环氧开环,进而芳构化,一锅法合成了2-羟基-9-芴酮衍生物2a～2e,收率89%～96%,其结构经¹H NMR,¹³C NMR和HR-MS(ESI)表征。其中,化合物2a结构由X-ray单晶衍射确定。2a(CCDC:2144829)属单斜晶系,空间群P2₁/c,晶胞参数a=3.9458(10)?,b=22.4460(7)?,c=14.7092(5)?,V=1294.1300(7)?³,Dc=1.3980 Mg/m³,Z=4,F(000)=568。     

对甲基苯磺酸亚铈催化一锅法合成取代2,3-二氢-4(1H)-喹唑啉酮

以对甲基苯磺酸亚铈为催化剂,靛红酸酐、醛和铵盐或伯胺为原料,在乙醇水溶液中三组分一锅法合成了一系列单取代和双取代2,3-二氢-4(1H)-喹唑啉酮衍生物。考察了溶剂条件及催化剂用量对产率的影响。经催化剂循环研究,催化活性无明显变化。产物的结构通过熔点、IR、1H NMR、13C NMR、质谱和元素分析进行测定和结构表征。     

一锅法合成2-硫脲嘧啶

采用一锅法合成了2-硫脲嘧啶,最佳反应条件为:硫脲33 mmol,n(乙酸乙酯)∶n(甲酸乙酯)∶n(甲醇钠)∶n(硫脲)=2.5∶2.0∶1.5∶1.0;乙酸乙酯与甲醇钠在甲苯(35 mL)中于80℃反应3 h;冷却后滴加甲酸乙酯,于25℃充分搅拌8 h后加入硫脲的乙醇(10 mL)溶液,回流反应3 h,收率54.7%。     

乙酸酐、H2O2和1,5二-羟基萘酚一锅合成胡桃醌

由乙酸酐和H2O2在无硫酸存在下合成过氧乙酸,然后向其滴加1,5-二萘酚的甲醇溶液,在一锅内简便地合成了胡桃醌。产物用苯重结晶,其结构经HPLC、UV-Vis、FTIR、^1H NMR和^13C NMR测试技术进行了表征和证实。考察了原料摩尔比、反应温度和反应时间对产率的影响。最佳反应条件为：n（1,5-二萘酚）：n（乙酸酐）：n（H2O2）=1：4：8,反应温度为40-60℃,反应时间为5．5h,产率68％。结果表明,一锅法合成不用硫酸,无需真空蒸馏纯化过氧乙酸,是合成胡桃醌的简便方法。     

一锅法合成1,4-二叔丁氧羰基亚精胺

以丁二胺和丙烯腈为原料,采用一锅法制得N1,N4-二叔丁氧羰基-N4-(2-氰乙基)-1,4-丁二胺(3);以甲基叔丁基醚为溶剂,3经LiAlH4还原合成了1,4-二叔丁氧羰基亚精胺,其结构经1H NMR和MS确证。     

一锅合成法的新进展

综述了最近十余年一锅合成法在有机合成中的主要应用及新进展。参考文献４７篇。     

乙酸酐、H2O2和1,5-二羟基萘酚一锅合成胡桃醌

由乙酸酐和H2O2在无硫酸存在下合成过氧乙酸,然后向其滴加1,5-二萘酚的甲醇溶液,在一锅内简便地合成了胡桃醌。产物用苯重结晶,其结构经HPLC、UV-Vis、FTIR、1H NMR和13C NMR测试技术进行了表征和证实。考察了原料摩尔比、反应温度和反应时间对产率的影响。最佳反应条件为:n(1,5-二萘酚)∶n(乙酸酐)∶n(H2O2)=1∶4∶8,反应温度为40~60℃,反应时间为5.5 h,产率68%。结果表明,一锅法合成不用硫酸,无需真空蒸馏纯化过氧乙酸,是合成胡桃醌的简便方法。     

"一锅法"合成5-氟-2-羟基-苯乙酮

对合成5-氟-2-羟基-苯乙酮的方法进行改进,将原来的两步反应合并为一步,去掉了中间产物酯的繁琐分离和纯化,大大缩短了反应时间,操作简便,收率88．9％,适用于工业化生产。     

一锅法合成新型异吲哚啉酮衍生物

以二价铜为催化剂,邻溴苯甲酸、苯乙炔和伯胺为原料,经一锅法合成了12个以异吲哚啉酮为母核的新化合物,其结构经¹H NMR, ¹³C NMR 和HR-MS(ESI)表征。并对催化机理进行了探讨。     

A Practical Synthesis of 2,4-Dichloro-3-methyl-6-nitrophenol

2,4-Dichloro-3-methyl-6-nitrophenol 2 was prepared by KOH/H₂O hydrolysis of a product mixture obtained from chlorination of p-nitrotoluene in the presence of a phase transfer catalyst. A 95–99% yield of 2 based on 2,3,6-trichloro-4-nitrotoluene, 4 (major chlorination product) was achieved in >95% purity.     

3,5-二氯-2,4,6-三硝基苯胺及其衍生物的合成

分别以3,5-二氯苯胺为原料,经N保护、硝化、水解以及以1,3,5-三氯-2,4,6-三硝基苯(TCTNB)为原料,经叔丁胺化,再在三氟乙酸中脱叔丁基2种方法合成了3,5-二氯-2,4,6-三硝基苯胺。 与甲胺反应,合成了3,5-二甲氨基-2,4,6-三硝基苯胺,收率85%,再用混酸硝化合成了3,5-二甲硝胺基-2,4,6-三硝基苯胺的硝酸盐,收率70%。 采用核磁共振、质谱、红外和元素分析等进行了结构表征。 探讨了不同参数下TCTNB的氨化结果。 优化的条件为：n(TCTNB)∶n(叔丁胺)=1∶2,CuO为催化剂,KHCO3为碱。     

2,4-二氯-3-乙基-6-硝基苯酚的合成

2,4 二氯 3 乙基 6 硝基苯酚是合成照相显影剂的重要中间体.本文以三氯异氰脲酸(TCIA)为氯化试剂,对4 硝基乙苯氯化,再经碱解和酸化,合成该中间体.由于TCIA易于计量、相应反应过程易于监控及环境污染轻微,大大简化了反应操作,也降低了合成成本.经过详细考察发现:氯化时TCIA按1 5倍投料,不仅反应收率较高,同时也有效地减少了四氯副产物的生成.此外,氯化所使用的溶剂硫酸、碱解采用的溶剂甲醇,均可以回收循环使用,而几乎不影响相应实验结果.     

Synthesis of 2,4-dimethyl-6-oxo-2,4-heptadienoic acid derivatives from 2,4,6-trimethylpyrylium salts

Reaction 2,4,6-trimethylpyrylium salts with sodium cyanide in boiling water yielded the bicyclic lactone 1,3,5-trimethyl-6,8-dioxabicyclo[3.2.1]oct-2-en-7-one (6) along with a series of stereoisomers of 2,4-dimethyl-6-oxo-2,4-heptadienonitrile (5), which were the sole products when the reaction was carried out at room temperature. Compound 6, along with 3,5-dimethylphenol (7), was also obtained by refluxing 5 briefly in aqueous sodium hydroxide. However, when 5 was refluxed for a prolonged period in aqueous sodium acetate, 3,5-dimethyl-5-(2-oxopropyl)-furan-2-one (8), along with some 7, was generated instead. Compound 8 could also be produced from 6 on prolonged refluxing with aqueous sodium acetate, indicating that 6 was the kinetically-controlled and 8 the thermodynamically-controlled product.     

Synthesis of Chiral 2,4-Chiral 2,4-Dichloro-6-menthoxy-1,3,5-triazines and 2-Chloro-4, 6-Dimenthoxy-1,3,5-triazines as Enantiodifferentiating Coupling Reagents. An X-ray Study on 2,4,6-Trimenthoxy-1,3,5-triazine

Chiral mono-di-and trimenthoxy-1,3,5-triazines ware obtained from natural menthol and cyanuric chloride and applied as enantioselective coupling reagents in the synthesis of dipeptides.     

Synthesis of 2,4-Diarylcyclooctenopyridines with One-pot Four-component Reactions

An efficient one-pot four-component reaction has been developed for the synthesis of 2,4-diarylcyclooc-tenopyridines,in moderate yields. This route is an effective modified two-step synthesis of Krhnke pyridine and involves a four-component tandem reaction of pyridinium bromide with aromatic aldehydes and cyclooctanone in a system of NH4OAc/HOAc under microwave irradiation.     

气相色谱法测定鱼塘水中2,4-二氯-6-硝基苯酚和五氯酚含量

鱼塘水中残留的2种除草剂(2,4-二氯-6-硝基苯酚和五氯酚)经GDX201固相萃取柱富集后,用二氯甲烷洗脱,洗脱液用N-(叔丁基二甲硅烷基)-N甲基三氟乙酰胺衍生化,所得衍生化产物溶于乙酸乙酯中,用气相色谱法测定,从而获得上述2种除草剂的含量。2,4-二氯-6-硝基苯酚和五氯酚的峰面积与其质量浓度均在10～200μg.L-1内呈线性关系,检出限(3S/N)分别为0.09μg.L-1和0.16μg.L-1。以鱼塘水为基体进行加标回收试验,测得回收率依次为98.3%,98.6%;测定值的相对标准偏差(n=5)分别为3.6%和4.3%。     

Electronic and vibrational spectra of 2,4,6-trichloro- and 6-chloro-2,4-dimethoxypyrimidine

This paper presents the investigations of the electronic and vibrational spectra of 2,4,6-trichloropyrimidine and 6-chloro 2,4-dimethoxypyrimidine. The electronic spectra have been recorded in the liquid and vapour states in the region 50000-28000 cm⁻¹. Then-π and π-π transitions are classified in each case. Infrared absorption spectra of 2,4,6-trichloropyrimidine in nujol have been recorded in the region 4000-400 cm⁻¹. It is concluded that substituents like Cl or OCH₃ do not have much influence on thesp ² electron of the nitrogen atom of the ring. From infrared studies the mass-dependent modes and the modes insensitive to substitution have been pointed out. The assignments are tentative and are based on the group frequency approach and data available for similar molecules.     

One-pot Synthesis of 2,4-Diamino-substituted Thieno[3,2-d]pyrimidines

An efficient one‐pot synthetic approach to 2,4‐diamino‐substituted thieno[3,2‐d]pyrimidines from 2,4‐dichlorothieno[3,2‐d]pyrimidine was described.