Synthesis of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) in aqueous medium at room temperature

The reaction of dimedone with various aromatic aldehydes produces 2,2'-arylmethylene bis (3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) in excellent yields. The reactions occur in water as solvent at room temperature and avoiding the addition of any catalyst. The workup procedure is very simple and the products do not required further purification.     

An efficient synthesis of 2,2′-arylmethylene bis-(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 1,8-dioxooctahydroxanthenes using ZnO and ZnO-acetyl chloride

<正>2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl chloride catalysts the reaction is limited to give only 1,8-dioxo-octahydroxanthenes 3a-k in very good yields.     

芳亚甲基双(3-羟基-5,5-二甲基-2-环己烯-1-酮)类化合物的合成

在水溶剂中,酸性离子液体[bmim][HSO4]可以有效地催化芳香醛与5,5-二甲基-1,3-环己二酮反应3～5h,得到产率为76%～86%的芳亚甲基双(3-羟基-5,5-二甲基-2-环己烯-1-酮)类化合物.该反应产物后处理简单,催化剂可以回收利用.催化剂在循环使用五次时对产物的收率影响不大,是一种环境友好的绿色合成方法.     

Uncatalysed Knoevenagel condensation in aqueous medium at room temperature

Knoevenagel condensation of various aromatic and heteroaromatic aldehydes with active methylene compounds like malononitrile, ethyl cyanoacetamide, ethyl cyanoacetate, barbituric acids, Meldrum’s acid, dimedone and pyrazolone proceeds smoothly with stirring in an aqueous medium. The reactions occur at room temperature giving excellent yields of the products. The work-up procedure is very simple and the products do not require further purification.     

Synthesis and Crystal Structure of 5,5-Dimethyl-2-(4-chlorophenyl)(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one-2-yl)methyl-3-(4-methoxyphenylamino)-2-cyclohexene-1-one

The title compound 5,5-dimethyl-2-(4-chlorophenyl)(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one-2-yl)methyl-3-(4-methoxyphenylamino)-2-cyclohexen-1-one has been synthesized,and its crystal structure was characterized by X-ray single-crystal diffraction. The crystal belongs to monoclinic,space group P21/c with a=9.4193(13),b=26.915(4),c=21.188(3),β =101.906(3)°,V =5256.2(13)3,Z =4,C60H68Cl2N2O8,Mr=1016.06,Dc=1.284 g/cm3,F(000)=2160,λ(MoKα)=0.71073,μ=0.182 mm–1,R=0.0530 and wR=0.1131 for 4128 observed reflections (I>2σ(I)). X-ray analysis reveals that there are two independent molecules in the unit and the cyclohexenone rings adopt different conformations. In addition,there are four intramolecular hydrogen bonds in the title molecule.     

环状碳酸酯5,5-二甲基-1,3-二噁烷-2-酮的合成

在三乙胺存在下,2,2-二甲基-1,3-丙二醇和氯甲酸乙酯反应合成了环状碳酸酯5,5-二甲基-1,3-二噁烷-2-酮,其结构经1H NMR和IR表征。提出了可能的反应机理。     

3-邻氯苯基-3-(5,5二甲基-3-羟基-2-环己烯-1-酮-2-基)丙酸乙酯的合成和晶体结构

标题化合物C19H23O4Cl（4）是由邻氯苯甲醛（1）与5，5-二甲基-1，3-环己二酮（2）、2，2-二甲基-1，3-二氧六环-4，6-二酮（3）在乙醇中反应而得。结构通过单晶X-射线衍射分析确定，其晶体属于单斜晶系，空间群晶体结构用直接法解出，使用全矩阵最小二乘法对原子参数进行修正，最后的偏离因子R＝0．034，Rw＝0．042。在晶体结构中存在一个共轭的烯醇结构。单晶X-射线分析表明；平面1（C（1）～C（6）、Cl）和平面2（C（8）～C（10）、C（12）、C（13））之间的两面角为97．11°，原子C（7）呈变形的四面体构型。     

A Convenient Synthesis of 3-Aryl-3-(5,5-dimethyl-3-hydroxy-2-cyclohexene-1-one-2-yl) Propanic Esters Catalyzed by KF-Alumina

A series of 3-aryl-3-(5,5-dimethyl-3-hydroxy-2-cyclohexene-1-one-2-yl) propanic esters were synthesized by reaction of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione and isopropylidene malonate in alcohols catalyzed by KF-Al₂O₃. The structure of 4a was determined by X-ray analysis.     

2,2’-(4-氯苯基)亚甲基双(3-羟基-5,5-二甲基-2-环己烯-1酮)的晶体结构

标题化合物C23H27O4Cl是由邻氯苯甲醛与5，5-二甲基-1，3-环己二酮在N，N-二甲基甲酰胺中反应而得。结构通过单晶X-射线衍射法测定，其晶体属于单斜晶系，空间群晶体结构用直接法解出，使用全矩阵最小二乘法对原子参数进行修正，最后的偏离因子为在晶体结构中，存在两个共轭的烯醇式结构。四个C－O健长分别为1．283（2），1．285（2），1．287（3）和1．298（2）     

Synthesis,characterization and catalytic evaluation of ZrCl4:Mg(ClO4)2 for the synthesis of 1,3-diaryl-3-(phenylthio)propan-1-one

Herein we demonstrate a novel tandem aldol condensation-thia-Michael addition process using a bimetallic catalyst (ZrCl₄:Mg(ClO₄)₂). The novel bimetallic catalyst performs under very mild conditions. The catalyst helps in the efficient synthesis of β-mercapto carbonyl derivatives from chalcones and thiols in one-pot method. We successfully used the zirconium tetrachloride in combination with magnesium perchlorate in a specific ratio which is considered as green catalyst and efficiently worked for the synthesis of β-mercapto carbonyl derivatives at room temperature. This is the first report which presents the use of ZrCl₄:Mg(ClO₄)₂ without calcination. Significant advantages of this method are that the reaction is performed under mild conditions, shows good selectivity and high yield, within short reaction times and easy workup. This method minimizes waste disposal problems as well, which makes present method highly efficient and convenient. The synthesized bimetallic catalyst was characterized by different analytical techniques such as XRD and SEM. Subsequently, the synthesized β-mercapto carbonyl products were identified by using FTIR, NMR, GC–MS and CHN elemental analyzer.     

Willgerodt-Kindler reaction at room temperature: Synthesis of thioamides from aromatic aldehydes and cyclic secondary amines

A simple method for the synthesis of thioamide derivatives in DMSO at room temperature and at 120 °C has been developed. Total 27 compounds were prepared under both conditions via a one-pot, three component reaction between substituted aromatic aldehydes, elemental sulfur powder, and cyclic secondary amines. By optimizing the mole ratio of sulfur powder and amines, we have successfully carried out Willgerodt-Kindler reaction of aromatic aldehydes at room temperature. At 120 °C, it is catalyst free reaction with lower reaction time whereas at room temperature, due to the additional amine molecule, Willgerodt-Kindler reaction of aromatic aldehydes is successfully carried out at room temperature. On gram-scale, the reaction is successfully attempted under both conditions with good yields.     

Crystal Structure of Methyl 3- (2-chlorophenyl )-3- (5, 5-dimethyl-3-hydroxy-2-cyclohexene- 1-one-2-yl) propionate

1INTRODUCTIONInorganicsolidsupportsascatalystshavebeenwellstudied,becauseoftheirap-plicationsinorganicsynthese('~".Recently,wehavereportedtheKnoevenagelcon-densationcatalysedbyKF-Al,O,['i.Inthispaper,wediscussedthecrystalstruc-tureofthetitlecomPoundsynthesizedbythereactionof2-chlorobenzaldehydey5,5-dimethyl-1,3-cyclohexanedioneandisopropylidenemalonateinmethanolcatalyzedbyKF-Alzo,'Inordertoconfirmthestructureofthetitlecompound,theX-raycrys-tallOgraphicstudywascarriedout.2EXPER1MEN…     

3-(Substituted Aryl)-1-(benzofuran-2-yl)-2-propenones,Part 1: Synthesis and Characterization of Some Novel Chalcones

Synthesis and characterization of some novel chalcones by condensation of 2-acetylbenzofurane and various aromatic aldehydes is described.     

3,3-二甲基-9-(5,5-二甲基-3-羟基-2-环己烯-1-酮-2-基)-1-氧代-2,3,4,9-四氢化氧杂蒽的合成和晶体结构

标题化合物C23H26O4是由水杨醛与5，5-二甲基-1，3-环己二酮在N，N-二甲基甲酰胺中反应而得．结构通过单晶X-射线行射法确定，其晶体属于单料晶系，空间群P21/c，a=7．056（7），b=20.263（3），c=13．665（2）A，β＝93．32（1）°，V=1950．7（4）A3，Mr=366．46，Dc=1.248g／cm3，Z=4，μ（MoKa）=0．84cm－1，F（000）=784。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，最后的偏离因子R=0．068，Rw=0．075。晶体结构分析结果表明，分子中存在一个共轭的烯醇式结构。     

Novel heterocyclization of 3-(2-aminophenylamino)- 5,5-dimethyl-2-cyclohexen-1-one

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Effective preparation of 5, 5'-(arylmethylene)bis(4-hydroxythiazole-2(3H)-one) in an aqueous fluoroalcohol solvent system under ultrasound irradiation at room temperature

A green and convenient approach for the synthesis of a series of 5,5'-(arylmethylene)bis(4-hydroxythiazole-2(3H)-one) by the reaction of aryl aldehydes, monochloroacetic acid and ammonium thiocyanate in water/trifluoroethanol(TFE) (1:1) under ultrasound irradiation at room temperature is described. This method provides several advantages such as environmental friendliness, shorter time, excellent yields, and simple work-up procedure.     

Synthesis of some cyclopentenones and crystal structure of 4-hydroxy-3,4-bis(4-methoxyphenyl)-5,5-dimethyl-2-cyclopenten-1-one

Abstract  

Sodium-hydroxide-catalyzed condensation of di-p-methyl- and di-p-methoxybenzil with acetone derivatives was investigated in methanol. Di- and trisubstituted products were obtained as cyclopentenones, while tetraaryl-substituted systems were isolated as cyclopentadienones. The structures of the products were identified by elemental analysis, infrared (IR), nuclear magnetic resonance (¹H NMR), and mass spectroscopy. The solid-state structure of 4-hydroxy-3,4-bis(4-methoxyphenyl)-5,5-dimethyl-2-cyclopenten-1-one was further studied by single-crystal X-ray diffraction analysis. The title compound crystallizes in an orthorhombic space group and intermolecular O–H···O and C–H···O hydrogen bonds stabilize the crystal lattice.     

5-羟基-3,4-二氢异喹啉-1-酮的合成

以异喹啉为起始原料,经成盐、磺化得异喹啉-5-磺酸(3),3与熔融的氢氧化钠和氢氧化钾反应得1,5-二羟基异喹啉(4),以5%Pd-C为催化剂还原4得5-羟基-3,4-二氢异喹啉-1-酮(1),总收率47.6%。1的结构经1H NMR和MS确证。