一锅两步法合成1,4-二芳基取代-1,3-丁二烯类化合物

1,3-共轭烯烃不仅是有机合成不可或缺的原料或中间体,许多聚合物、天然产物和具有生理活性化合物的核心骨架都含有1,3-丁二烯结构单元.简便而有效的1,3-共轭烯烃合成方法一直是化学家们感兴趣的研究课题,在已有共轭烯烃的合成方法中,钯催化烯基卤与端烯的Heck交叉偶联反应占据了主要地位.最近,简单化合物的"一锅法"串联反...     

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%。     

一锅法合成N-呋喃酮基磺酰腙类化合物

以3,4-二卤-2(5H)-呋喃酮、磺酰肼和羰基化合物为起始原料,利用一锅法策略同时构建一个C—N键和一个C=N键,以良好收率合成一系列N-2(5H)-呋喃酮基磺酰腙类化合物.这种无需金属催化的转化在室温下就可实现,且具有好的底物适用性和选择性,即使对于Csp2—C1型的3,4-二氯-2(5H)-呋喃酮类底物,这种绿色...     

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。     

乙二胺四乙酸四钠“一锅法”催化合成2-氨基-2-色烯衍生物

乙二胺四乙酸四钠能有效地催化芳香醛、丙二腈、1-萘酚在体积分数为95%乙醇介质中一锅法合成2-氨基-2-色烯衍生物. 该法具有催化剂价廉易得、反应条件温和、实验操作和后处理简便、收率高、催化剂能重复使用等优点.     

四组分一锅法合成多取代吡喃[2,3-c]吡唑-5-腈

在三乙胺催化下,以乙酰乙酸甲酯、苯肼、芳醛和丙二腈等4组分为原料,经一锅法合成了一系列多取代的吡喃并[2,3-c]吡唑衍生物(5a～5j),反应在10～15 min内即可完成.所有产物由IR、1HNMR和MS确证.该方法具有产率高、操作简单等优点.     

一锅法合成缩氨硫脲类化合物

香草醛和肼基二硫代甲酸甲酯经一锅法合成了两个新的缩氨硫脲类化合物,其结构经UV, 1H NMR, IR和元素分析表征.     

无溶剂无催化条件下一锅合成芳酰基腈化合物

无溶剂无催化剂条件下,以芳香酸、二氯亚砜和铁氰化钾为原料,经氯化、氰化两步一锅合成了一系列芳酰基腈化合物。 考察了氰化过程中反应温度、反应时间对产率的影响。 实验结果表明,其最佳反应条件为：反应温度为180 ℃,反应时间为2 h,产物收率达71%~92%。 产物经IR、1H NMR和13C NMR分析确认。 本方法具有工艺操作简单、产率高、无溶剂无催化和环境友好等优点。     

一锅法合成3-腈基-4苯并吡喃酮类化合物

以各种取代的邻羟基苯乙酮为起始原料,经Vilsmeier试剂环合得中间体3-甲酰基色酮,不经分离纯化,直接与盐酸羟胺反应合成了一系列3-腈基-4苯并吡喃酮类化合物,总收率47%~74%,其结构经1HNMR,IR和MS确证。     

碱性条件下4(3H)-喹唑啉酮的一锅合成

研究了一种碱性条件下由邻氨基芳香腈1与醛2一锅合成4(3H)-喹唑啉酮3的新方法.反应经由亲核加成、分子内的Pinner关环、Dimroth重排和氧化脱氢串联转化而成.产物结构经1H NMR,13C NMR,IR和元素分析确证.     

一锅法合成新型羟基环戊烯酮化合物

以二芳基乙酮（4a~4f）和取代丙酮（5a~5c）为原料,KHCO₃为碱,100 ℃空气条件下,在DMSO中经二芳基乙酮氧化、羟醛缩合一锅法合成了12个羟基环戊烯酮化合物（6a~6l）,其中6d, 6h和6i为新化合物,其结构经¹H NMR, ¹³C NMR和HR-MS(ESI)表征。     

一锅法合成吡咯并[2,1-a]异喹啉类化合物

以[3+2]环加成反应产物吡咯烷酮作为底物（1）,经过一锅法N-烯丙基化/分子内Heck环合反应合成了12个吡咯并[2,1-a]异喹啉类化合物2a~2l,产物收率50%~79%,其结构经¹H NMR, ¹³C NMR,¹⁹F NMR和HR-MS(ESI)表征。      

One-pot approach to 2,3-disubstituted-2,3-dihydro-4-quinolones from 2-alkynylbenzamides

Concise and efficient syntheses of various trans-2,3-disubstituted-2,3-dihydro-4-quinolones have been achieved via tandem Hofmann-type rearrangement of 2-alkynylbenzamides, nucleophilic addition of alcohols to the isocyanate intermediates, intermolecular [2+2]-cycloaddition with carbon-carbon triple bonds and aldehydes, and intramolecular aminocyclization of nitrogen of carbamates to the α,β-unsaturated ketones.     

Improved One-pot Synthesis of 4,6-Dihydroxyisophthalic Acid and 2,3-Dihydroxyterephthalic Acid

An improved method for the large-scale preparation of 4,6-dihydroxyisophthalic acid and 2,3-dihydroxyterephthalic acid has been developed.Compared to the previous procedures,this new process-requires much lower CO2 pressure of 0.3 Mpa and shorter reaction time.thus providing a convenient access for large-scale synthesis.The yield is high （93% and 65%,respectively）, and the oxidation of phenol is nearly inhibited,neither decolorization nor further chromatographic purification is required.     

Synthesis of Heterocyclic Compounds from 2-Phenyl-l,2,3-Triazole-4-Formylhydrize

Many compounds containing the 1,3,4-oxadiazole and/or1,2,3(or 4)-triazole and thiadiazole ring system are reported to possess antibacterial^[1], antiinflammatory^[2], anticonrulsant^[3],CNS stimulant^[4] and pesticidal^[5] activities and excellent anthelmintic properties^[6,7]. In view of this and the results of the combined different nuclei system in a molecular always enhancing the therapeutic activities,the present work deals with the synthesis of the combined different pharmacologically active nuclei system mentioned above in a molecular through some new method.     

Microwave Assisted One-pot Synthesis of 2-Amino-4H-chromenes and Spiropyrano[2,3-d]pyrimidine

A convenient and efficient method using microwave assisted one pot synthesis reactions for synthesis of 4H‐benzo[f]chromenes by the reaction of aromatic aldehydes with a mixture of malononitrile and naphthols was examined. The synthesis of spiropyrano[2,3‐d]pyrimidines by the reaction of isatin with malononitrile and barbituric acid and/or thiobarbituric acid was investigated. The versatility of the method was also examined through the reaction of aromatic aldehydes and malononitrile with various reagents.     

Interaction of 1-Benzyl-4-benzoyl-5-phenyl-2,3-dihydro-2,3-pyrroledione with Ketene Diethylacetal: Synthesis and Crystal and Molecular Structure of 1-Benzyl-4-benzoyl-3-hydroxy-5-phenyl-5-ethoxycarbonylmethyl-2,5-dihydro-2-pyrrolone

1-Benzyl-4-benzoyl-5-phenyl-2,3-dihydro-2,3-pyrroledione reacts with ketene diethylacetal, forming 1-benzyl-4-benzoyl-3-hydroxy-5-phenyl-5-ethoxycarbonylmethyl-2,5-dihydro-2-pyrrolone, whose crystal and molecular structure was studied by XRD.     

Crystal Structures of Two Compounds from a Rapid and One-pot Synthesis Method

Compounds 1(C_(17)H_(22)N_2,M_r = 254.37) and 2(C_(13)H_(16)N_2,M_r = 200.28) have been synthesized and their crystal structures were determined by single-crystal X-ray diffraction. Crystal 1 belongs to triclinic,space group P1 with a = 6.524(2),b = 8.987(3),c = 12.746(5) ?,α = 95.220(7),β = 90.055(6),γ = 104.431(6)°,V = 720.5(4) ?~3,Z = 2,D_c = 1.173 g/cm~3,μ(Mo Kα) = 0.069 mm~(-1),F(000) = 276,R = 0.0578 and wR = 0.1221 for 1487 observed reflections I 2s(I). Crystal 2 is of tetragonal system,space group I4_1/a with a = 20.763(10),b = 20.763(10),c = 11.427(6) ?,V = 4926(4) ?~3,Z = 16,D_c = 1.080 g/cm~3,μ(Mo Kα) = 0.065 mm~(-1),F(000) = 1728,R = 0.0581 and wR = 0.1288 for 1408 observed reflections with I 2σ(I). Although the two compounds are similar with the same pyrazole and benzene ring units,X-ray analysis reveals that their structures are completely different maybe caused by steric effects.