6-氨基-4-芳基-3-异丙基-1-苯基-4H-吡喃[2,3-c]吡唑-5-腈的三组分一锅法合成

在三乙胺的催化下,以1-苯基-3-异丙基吡唑-5-酮、芳香甲醛和丙二腈三组分为原料,经一锅法合成了一系列6-氨基-4-芳基-3-异丙基-1-苯基-4H-吡喃[2,3-c]吡唑-5-腈类化合物4a～4j.与常规合成法相比,该方法具有操作简单及产率较高等优点.产物的结构通过IR,1H NMR和质谱进行了确定.     

2,3a-二氢-苯并吡喃[4,3-c]吡唑-3-酮类衍生物的合成及其活性

为了进一步寻找新型黄酮类农药,以苯并吡喃[4,3-c]并吡唑-3-酮为先导结构,以4-氯苯甲醚为起始原料.设计合成了33种新型的2,3a-二苯并吡喃[4,3.c]吡唑-3-酮类化合物,其结构经MS,~1H NMR和元素分析确证.并对化合物7k的单晶进行了结构测定,对目标化合物进行了杀虫和杀菌活性测试.结果表明,大部分化合物显示出一定的杀菌活性和弱的杀虫活性.     

磷酸氢二钾催化多组分一锅法反应合成1,4-二氢吡喃并[2,3-c]吡唑衍生物

绿色、简便、高效的催化四组分反应合成吡喃并[2,3-c]吡唑类杂环化合物是当今有机化学领域的研究热点。 本文发展了在水与聚乙二醇(PEG-200)的混合液中,廉价易得的磷酸氢二钾(K₂HPO₄·3H₂O)催化乙酰乙酸乙酯、水合肼、芳香醛和丙二腈的多组分“一锅法”反应,合成一系列1,4-二氢吡喃并[2,3-c]吡唑-5-腈衍生物,产率为88%~98%。 该方法避免了使用复杂昂贵的催化剂和繁琐的纯化过程。     

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.     

1-苯基-5-(3,4-二甲氧基苯基)-3-羟基吡唑的合成和晶体结构

标题化合物(I)是由 1-苯基-5-(3, 4-二甲氧基苯基)-3-吡唑烷酮在 FeCl3催化下被氧气氧化得到的。它的结构经过了元素分析、IR、1H NMR 的表征,用 X-射线衍射法测定了化合物的晶体结构。C17H16N2O3(I)的晶体学参数分别为:三斜晶系,P1空间群,a = 6.6600(13),b = 8.4200(17),c = 14.060(3) ?,α= 85.61(3), β= 76.89(3), γ= 81.18(3)?, Z = 2, Dc= 1.298g/cm3, V = 758.1(3) ?3, Mr = 296.32,μ= 0.090 mm–1, F(000) = 312, R = 0.048,wR = 0.1231。结构测定表明化合物的吡唑环存在着一个大的共轭体系,含有一个稳定的烯醇结构,分子通过分子间的氢键形成了网状的结构。     

L-脯氨酸催化一锅法合成4 H-吡喃并[2,3-c]吡唑衍生物

以L-脯氨酸为绿色催化剂,3-甲基-5-吡唑酮(或1-苯基取代物)和芳醛及丙二腈为原料,就微波辅助的一锅法成环缩合反应进行研究。实验结果表明,乙醇/水为溶剂,催化剂用量10mol%,微波功率300W和80℃下反应10～15 min,即可得到4H-吡喃并[2,3-c]吡唑类化合物(4a～4j),合成收率达85～94%。该方法具有产率高、反应时间短、操作简单等优点。     

3a, 4-二氢-苯并吡喃[4,3-c]吡唑-3(2H)-酮类衍生物的合成及其活性

设计合成了33种新型的3a, 4-二氢-苯并吡喃[4,3-c]吡唑-3(2H)-酮类化合物,其结构经MS,1H NMR和元素分析的确证。并对化合物7k的单晶进行了结构测定。初步生物活性测试表明标题化合物具有一定的杀虫杀菌活性。     

碱性离子液体催化“一锅法”合成1,4-二氢吡喃并[2,3-c]吡唑

在碱性离子液体氢氧化1-丁基-3-甲基咪唑([bmim]OH)催化作用下,由芳香醛、丙二腈、苯甲酰乙酸乙酯和肼或苯肼"一锅法"合成了一系列1,4-二氢吡喃并[2,3-c]吡唑化合物.实验中考察了催化剂、反应温度、催化剂用量、溶剂对反应的影响,确定了最优反应条件,给出了可能的反应机理.此外催化剂可以方便地收回,且循环使用四次其催化活性并没有显著降低.目标产物经过了1H NMR,IR,MS和元素分析确证.合成方法条件温和、反应时间短、产率高且对环境友好.     

10-氯-5-二乙氧基甲基-1,3-二甲基色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮的合成和晶体结构

利用L-脯氨酸催化的5-氯水杨醛(1)与6-甲基-4-羟基吡喃酮(2)的缩合反应及硫酸铜催化下与1,3-二甲基-5-氨基吡唑(3)的串联反应,合成得到了10-氯-1,3-二甲基-5-(2-氧代丙基)色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(4)和10-氯-5-二乙氧基甲基-1,3-二甲基色烯并[4,3-d]吡唑并[3,4-b]吡啶-6(3H)-酮(5).化合物5的结构通过单晶X射线衍射法确定:晶体属于三斜晶系,空间群P-1;相对分子质量Mr=803.68;晶胞参数a=1.03160(10)nm,b=1.42900(13)nm,c=1.44268(15)nm;V=1.9448(3)nm~3;Z=2;晶胞密度Dc=1.372g/cm~3;吸收系数μ=0.228mm-1;单胞中电子的数目F(000)=840.晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R=0.0681,w R=0.2051.在晶体结构中色烯环与吡啶环及吡唑环近似于共平面.     

超声作用下四组分一锅法合成二氢吡喃并[2,3-c]吡唑衍生物

报道了在超声波作用下,乙醇作溶剂,无任何催化剂下由醛、水合肼、乙酰乙酸乙酯(或丁酰乙酸乙酯)和丙二腈四组分简单、方便、有效地合成了一系列二氢吡喃并[2,3-c]吡唑衍生物.该方法具有产物产率高、反应时间短、条件温和及操作简单的优点.     

水中3-甲基-6-氨基-5-氰基-4-芳基-1-苯基-1，4-二氢吡喃[2，3-c]吡唑的洁净合成

在水溶剂中并有三乙基苄基氯化铵（TEBA）存在下，取代芳亚甲基丙二腈与3- 甲基-1-苯基-2-吡唑啉-5-酮缩合成为3-甲基-6-氨基-5-氰基-4-芳基-1-苯基-1， 4-二氢吡喃[2,3-c]吡唑，此法为相应化合物的合成提供了一种快速、方便、高效 和洁净的方法。     

Electro-catalyzed multicomponent transformation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one to 1,4-dihydropyrano[2,3-c]pyrazole derivatives in green medium

An efficient and convenient synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives is described, using the electrogenerated anion of ethanol as the base in the presence of sodium bromide as an supporting electrolyte in a one-pot, three component condensation of malononitrile, aromatic aldehydes and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one. The reaction is carried out in an undivided cell containing an iron electrode as the cathode and a graphite electrode as the anode, at a constant current at room temperature.     

微波促进下6-氨基-4-芳基-5-氰基-3-甲基-1-苯基吡啶[2,3-c]并吡唑的合成

5-氨基-3-甲基-1-苯基吡唑与芳亚甲基丙二腈在少量乙二醇中, 经微波辐射得到6-氨基-4-芳基-5-氰基-3-甲基-1-苯基吡啶[2,3-c]并吡唑衍生物, 反应4～8 min完成, 产率为71%～90%, 产物结构通过红外、核磁共振、元素分析及单晶X射线分析表征.     

Synthesis and Crystal Structure of Ethyl（2-amino-4-（3-nitrophenyl）-1,4-dihydro-2H-pyrano[3,2-h]quinolin-3-）carboxylate

1 INTRODUCTION 2-Aminochromene is an important class of com- pounds found as the main compounds of many naturally occurring products employed as cos- metics and pigments[1] and utilized as potential biodegradable agrochemicals[2～4]. The utility of fluoride salts as potential base in variety of syn- thetic reactions has been recognized in recent years[5, 6]. However, low solubility of fluoride salts in ordinary solvents limits their wide applications in organic syntheses. On the other ha…     

Synthesis of 6-Amino-2,4-dihydropyrano[2,3-c]pyrazol-5-carbonitriles Catalyzed by Silica-Supported Tetramethylguanidine Under Solvent-Free Conditions

An efficient, high-yielding, and rapid protocol has been developed for the synthesis of diversity-oriented 6-amino-2,4-dihydropyrano[2,3-c]pyrazol-5-carbonitriles derivatives via a four-component, one-pot cyclocondensation reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes, and malononitrile using silica-supported tetramethylguanidine as a heterogeneous catalyst for the first time. The protocol proves to be efficient and environmentally benign in terms of very easy workup, good yields, and ease of recovery of catalyst. In addition, the present method is superior in terms of green media, the amount of catalyst, and reaction time.     

An Efficient Four-Component Synthesis of Multisubstituted Pyrano[2,3-c]pyrazole

A series of substituted pyrano[2,3-c]pyrazole derivatives were synthesized by a one-pot reaction of methyl 4-methyl-3-oxovalerate, phenylhydrazine, aromatic aldehyde, and malononitrile in ethanol with catalysis by triethylamine. The title compounds were obtained in good to excellent yields. A possible mechanism for this reaction was proposed.     

金属氯化物对硼氢化钠还原α-氯代苯乙酮的影响

以芳醛、麦氏酸和3-甲基-1-苯基-5-氨基吡唑为原料, 经微波辐射一步得到4-芳基-3-甲基-6-氧代-1-苯基-4,5,6,7-四氢吡啶并[2,3-c]吡唑衍生物, 反应2～6 min完成, 产率高. 产物结构通过红外、核磁共振、元素分析及单晶X射线分析确证.     

Synthesis and Crystal Structure of 7-Amino-2,3,4,5-tetrahydro- 1,3-dimethyl- 5-（2-nitrophenyl）-2,4-dioxo-lH-pyrano[2,3- d]pyrimidine-6-carbonitrile DMF Solvate

The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-（2-nitrophenyl）- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 （C19H20N6O6, Mr = 428.41） was synthesized and crystallized. The crystal belongs to the monoclinic system, space group P2 1/c with a = 11.383（2）, b = 13.372（2）, c = 13.673（2）A, β = 97.380（4）°, Z = 4, V = 2063.8（6）A^3, Dc = 1.379 g/cm^3,μ（MoKα） = 0.105 mm^-1, F（000） = 896, the final R = 0.0738 and wR = 0.1647 for 2964 observed reflections （I〉 2σ（I））. X-ray analysis reveals that the new pyran ring is coplanar, which is obviously different from those of other similar compounds. In addition, the unclassical hydrogen bonds of C-H…O and C-H…N are presented in the crystals except for the normal hydrogen bonds of N-H…O.     

Synthesis of 6-amino-4-aryl-5-cyano-3-(3-cyanopyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles and their hydrogenated analogs. Molecular structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole

Substituted 3-hydroxypyrazoles, which were prepared based on ethyl esters of substituted 4-(pyridin-2-ylthio)- or 4-(1,4-dihydropyridin-2-ylthio)acetoacetic acids and hydrazine hydrate, were used in the synthesis of 6-amino-4-aryl-5-cyano-3-(pyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles. The molecular and crystal structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole was established by X-ray diffraction analysis.     

Synthesis and Crystal Structure of 7,7- Dimethyl-2-amino-3-cyano-4-(3,4-methylenedioxylphenyl)- 5-oxo-5,6,7,8-tetrahydro-4H-benzo-[b]-pyran

1 INTRODUCTION Inorganic solid supports as catalysts resulting in higher selectivity, milder conditions and easier work-up has been reported as useful catalysts for many reactions [1~3]. Recently, we have reported the Knoevenagel condensation and some other reactions[4~6] catalyzed by KF-Al2O3. In this paper, we discussed the crystal structure of the title compound synthesized by the reaction of 2-cyano-3-(3,4-methylenedioxylphenyl)acrylonitrile and 5,5-dimethyl-1,3-cyclohexanedione in…