Potassium Fluoride-Modified Clay as a Reusable Heterogeneous Catalyst for One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones

Russian Journal of Organic Chemistry - Potassium fluoride-modified clay collected from the region of Agadir (Morocco) was used as a hetaerogeneous catalyst in the one-pot synthesis of...     

以磷酸二氢铵为催化剂一锅法合成 3,4-二氢嘧啶-2-酮(英文)

A one-pot three component Biginelli condensation of different substituted aromatic and aliphatic aldehydes with ethyl acetoacetate and urea to the respective 3,4-dihydropyrimidin-2-( 1H)-ones under sol...     

无溶剂条件下用于合成3,4-二氢嘧啶-2(1H)-酮的高效、可磁性回收Fe_3O_4纳米粒子催化剂(英文)

The catalytic activity of Fe3O4 nanoparticles (NPs) in a one-pot three component condensation reaction consisting of an aromatic aldehyde, urea or thiourea, and a β-dicarbonyl under solvent-free conditions was investigated. This reaction affords the corresponding dihydropyrimidinones (thiones) in high to excellent yields. Compared with the classical Biginelli reactions this method consistently gives a high yield, easy magnetic separation, a short reaction time, and catalyst reusability.     

高氯酸镁催化合成1,2,3,4-四氢嘧啶-2-酮

在高氯酸镁催化作用下,由醛、1,3-二羰基化合物、脲(硫脲)合成了一系列1,2,3,4-四氢嘧啶-2-酮,此合成方法反应温和、产率高,并且高氯酸镁具有能重复使用的优点.     

三氯化镧催化一锅法合成3,4-二氢嘧啶-2-酮

二氢嘧啶酮;三氯化镧催化一锅法合成3;4-二氢嘧啶-2-酮     

(英)硫酸氢钾高效催化一锅法合成5-未取代的3,4-二氢嘧啶-2(1H)-酮

无溶剂条件下,硫酸氢钾可有效催化芳香醛、苯乙酮衍生物和脲的三组分"一锅法"Biginelli反应来合成5-未取代的3,4-二氢嘧啶-2(1H)-酮。确定了优化反应条件。产品结构经IR、1H NMR、MS和元素分析进行表征。     

Simple and Efficient Synthesis of 2-Aryl-2,3-Dihydroquinolin-4(1H)-ones Using Silica Chloride as a New Catalyst Under Solvent-Free Conditions

A mild, efficient, and high-yielding method for the synthesis of 2-aryl-2,3-dihydroquinolin-4(1H)-ones from their corresponding 2-amino chalcones using silica chloride (SiO₂Cl) under solvent-free conditions is described. A series of 2-aryl-2,3-dihydroquinolin-4(1H)-ones containing both electron-donating and electron-withdrawing substituents were synthesized.     

Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Using Ce(SO4)2-SiO2 as a Heterogeneous and Recyclable Catalyst

A simple and efficient synthesis of 3,4-dihydropyrimidinones or thiones is described, using silica-supported ceric sulfate [Ce(SO₄)₂-SiO₂] as a heterogeneous catalyst from an aldehyde, 1,3-dicarbonyl compound, and urea or thiourea at 110 °C under solvent-free conditions. Compared with the classical Biginelli reaction, this new method consistently has better yields, short reaction time, easy separation, and tolerance toward various functional groups.     

Highly Efficient Synthesis of Substituted Benzenes in the Presence of B(HSO4)3 as a New and Reusable Catalyst Under Solvent-Free Conditions

A highly efficient and simple procedure for the synthesis of substituted benzenes is described. A broad range of ketones (alkyl–aryl ketones and cyclic ketones) were condensed via a cyclotrimerization reaction in the presence of catalytic amounts of boron sulfonic acid [B(HSO₄)₃], a new, highly efficient, and reusable catalyst, under solvent-free conditions. All reactions completed in short times without formation of any by-products. The catalyst was recovered and reused successfully for 15 cycles of the reaction.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications® to view the free supplemental file.     

Synthesis of New 2-Aryl Substituted 2,3-Dihydroquinazoline-4(1H)-ones Under Solvent-Free Conditions,Using Molecular Iodine as a Mild and Efficient Catalyst

A simple, inexpensive, and efficient one-pot synthesis of 2,3-dihydroquinazoline-4(1H)-one derivatives under solvent-free conditions using a catalytic amount of iodine with excellent product yields is reported. This methodology provides easy, quantitative access to various 2,3-dihydroquinazoline-4(1H)-one derivatives, using commercially available iodine as a catalyst.     

Zn3(BTC)2 as a Highly Efficient Reusable Catalyst for the Synthesis of 2‐Aryl‐1H‐Benzimidazole

Zn₃(BTC)₂ metal‐organic frameworks as recyclable and heterogeneous catalysts were effectively used to catalyze the synthesis of benzimidazole derivatives from o‐phenylendiamine and aldehydes in ethanol. This method provides 2‐aryl‐1H‐benzimidazoles in good to excellent yields with little catalyst loading. The catalyst was characterized using different techniques such as X‐ray diffraction (XRD), energy dispersive X‐ray (EDX) analysis, scanning electron microscopy (SEM), and Fourier transform infrared (FT‐IR) spectroscopy.     

Synthesis of 2-Arylquinazolin-4(3H)-one Derivatives Catalyzed by Iodine in [bmim+][ ]

Controlling selectivity of the reactions of aromatic aldehydes and 2-aminobenzamide in ionic liquid catalyzed by iodine at either room temperature or at 80 °C under nitrogen resulted in the synthesis of (E)-Schiff bases, 2,3-dihydro-2-arylquinazolin-4(1H)-one and 2-arylquinazolin-4(3H)-one derivatives, in excellent yields.     

Bioglycerol-Based Sulfonic Acid-Functionalized Carbon Catalyst as an Efficient and Reusable Catalyst for One-Pot Synthesis of 3- Substituted-2H-1,4-Benzothiazines

Abstract

A simple and efficient synthetic protocol has been developed for the synthesis of 3-substituted-2H-1,4-benzothiazines by using bioglycerol-based sulfonic acid-functionalized carbon catalyst, devoid of corrosive acidic and basic reagents. The developed method has the advantages of good to excellent yields, short reaction times, operational simplicity, and a recyclable catalyst.     

Disodium Hydrogen Phosphate as an Efficient and Cheap Catalyst for the Synthesis of 2-Aminochromenes

An efficient and convenient method for the synthesis of 2-aminochromene by the one-pot, three-component reaction of an aromatic aldehyde, malononitrile, and α- or β-naphthol in the presence of a catalytic amount of disodium hydrogen phosphate under solvent-free conditions is described.      

Urea/Thiourea as Ammonia Surrogate: A Catalyst-Free Synthesis of 2-Substituted 2,3-Dihydroquinazolin-4(1H)-ones/Quinazoline-4(3H)-ones

Urea/thiourea have been identified as an effective ammonia surrogate in the construction of quinazolin-4(3H)-one ring. This strategy afforded a simple and catalyst-free synthesis of 2-substituted 2,3-dihydroquinazolin-4(1H)-ones and quinazolin-4(3H)-ones via the reaction of isatoic anhydride and aryl aldehydes in the presence of urea or thiourea in ethanol. The reaction proceeded well to afford the quinazolin-4(3H)-one or its dihydro derivative, depending on the nature of carbonyl compounds employed.     

Al(HSO4)3 and Al2O3-SO3H as Efficient Catalysts for Modified Preparation of 3,4-Dihydropyrimidin-2 (1H)-ones/thiones

An environmentally friendly procedure for the preparation of dihydropyrimidinone derivatives or their sulfur analogues under thermal solvent-free conditions in the presence of aluminium hydrogen sulfate [Al(HSO₄)₃] and alumina sulfuric acid (Al₂O₃-SO₃H) as heterogeneous catalysts was developed.     

Efficient synthesis of some 3-arylisoquinolin-1(2H)-ones

A number of 3-arylisoquinolin-1(2H)-ones were efficiently prepared from the corresponding 3-aryl-isocoumarins by refluxing with methanamide. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1203–1208, August, 2008.     

甲烷磺酸钕催化"一锅法"合成3,4-二氢嘧啶-2-酮

在甲烷磺酸钕催化下,醛、β-二羰基化合物和脲在无水乙醇中进行环化缩合,反应条件为:醛30 mmol,β-二羰基化合物(乙酰乙酸乙酯、乙酰乙酸甲酯、戊二酮)35 mmol,脲45mmol,甲烷磺酸钕3 mmol,无水乙醇10 ml,加热回流0.5～2.0 h,通过一锅法有效地合成了高纯度3,4-二氢嘧啶-2-酮衍生物,产率69%～93%.该催化剂在反应过程中不水解,催化效率高,缩短了反应时间,且操作简便,改进了Biginelli反应.     

离子液体中Yb(OTf)_3催化下喹唑啉酮衍生物的绿色合成

以邻氨基苯甲酰胺和芳醛为原料,离子液体[BMIm]Br为溶剂,Yb(OTf)3为催化剂室温下合成了一系列的2-芳基-2,3-二氢化喹唑啉-4-(1H)-酮衍生物.和其他方法相比,该方法具有反应条件温和、产率高(85%～96%)、环境友好等优点.产物的结构通过熔点,IR,1H NMR和高分辨质谱分析确证.