(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。     

硝酸镧高效催化合成3,4-二氢嘧啶-2(1H)-(硫)酮

报道了以La(NO3)3催化芳香醛、β-酮酯和脲或硫脲-锅法合成3,4-二氢嘧啶-2(1H)-(硫)酮的简单、有效方法.与经典Biginelli反应条件相比,它具有产率高、反应时间短和操作简单等优点.所有目标化合物的结构经元素分析、IR、13C NMR和1H NMR确证.     

C(5)-对甲基苯甲酰取代的3,4-二氢嘧啶(硫)酮类化合物的微波无溶剂合成

Biginelli反应是约120年前意大利化学家Pietro Biginelli发现的,所涉及的就是乙酰乙酸乙酯、尿素和芳基醛的一锅酸催化环化缩合反应.大量的研究表明Biginelli反应的产物——二氢嘧啶酮类化合物因为具有显著的生理和药理活性以及结构变化的多样性使得人们对于Biginelli反应的关注度持续增高.讲述了在微波无溶剂条件下,通过醛、对甲基苯甲酰丙酮、尿素(硫脲)在对甲苯磺酸催化下进行的Biginelli反应的方法来合成5-(4-甲基苯甲酰基)-3,4-二氢嘧啶-2(1H)-酮(硫酮)类衍生物,不仅易得到且收率高.     

SmI2催化合成3,4-二氢嘧啶-2-酮衍生物

3,4-二氢嘧啶-2-酮衍生物是一类具有生物活性的杂环化合物,在作为钙拮抗剂、降压剂、α1-1-a拮抗物等方面已有广泛的应用.该类化合物的合成法近十年来一直是生物活性杂环化合物领域研究的热点之一.Lewis酸催化的Biginelli反应是"一锅化"得到3,4-二氢嘧啶-2-酮衍生物的有效方法[1-5].我们以价廉易得的SmI2成功催化Biginelli反应,生成多个3,4-二氢嘧啶-2-酮衍生物.该反应无需反应溶剂,产率中等到高,且适用底物范围较广.     

硅胶固载硫酸镧催化一锅法合成3,4-二氢嘧啶-2(1H)-酮

以硅胶固载硫酸镧作为催化剂,由芳香醛、β-酮酸酯和脲(硫脲)合成了相应的3,4-二氢嘧啶-2(1H)-酮化合物,考察了苯甲醛、乙酰乙酸乙酯、脲三组分发生Biginelli反应时的催化剂用量、反应物物质的量比、反应时间及催化剂重复使用对反应收率的影响;并利用核磁共振谱(1H NMR)和红外光谱(IR)表征了合成产物的结构...     

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(英文)

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。     

磺酸功能化介孔聚合物催化“一锅法”无溶剂合成3,4-二氢嘧啶-2(1H)-酮

通过软模剂合成方法合成了高度有序具有二维六方(p6mm)的FDU-15介孔聚合物材料.利用气固相磺化法制备得到新型磺酸基功能化介孔聚合物固体酸(FDU-SO3H).通过X-射线衍射(XRD)、扫描电镜(SEM)及元素分析等测试手段对FDU-SO3H介孔材料的物化性能进行了表征.在无溶剂条件下,FDU-SO3H能有效地催化以芳香醛、乙酰乙酸甲酯和尿素(或硫脲)的三组分一锅法的Biginelli反应.在优化实验的条件下,合成了一系列3,4-二氢嘧啶-2(1H)-酮衍生物.考察了加料顺序、溶剂及反应底物对Biginelli反应的影响.苯甲醛、乙酰乙酸甲酯和尿素在无溶剂,90℃加热1 h的条件下反应,3,4-二氢嘧啶-2(1H)-酮的产率为91%.探讨了Biginelli可能的反应机理.实验结果证明,FDU-SO3H不仅具有催化活性高、对环境友好及在空气中稳定等优点,而且重复使用后仍能保持优异的催化活性.     

二氧化硅负载磷钨酸催化合成3,4-二氢嘧啶-2(1H)-酮衍生物

以取代苯甲醛、乙酰乙酸乙酯和尿素为原料,以溶胶凝胶法制备二氧化硅负载的磷钨酸（H3PW12O40/SiO2）为催化剂,催化合成3,4-二氢嘧啶-2(1H)-酮,考察了三组分摩尔比、反应温度、催化剂用量及反应时间对反应收率的影响。 研究表明,H3PW12O40/SiO2是合成3,4-二氢嘧啶-2(1H)-酮的良性催化剂,在取代苯甲醛的用量为0.04 mol,反应温度为90 ℃的条件下,收率可达73.1%~88.4%。 催化剂和产品结构分别经IR、XRD、SEM和1H NMR、IR、MS等技术手段表征。     

微波辐射促进选择性合成4,6-二芳基-3,4-二氢嘧啶-2(1H)-酮和嘧啶-2(1H)-酮

探讨了在微波加热条件下,芳香醛、取代苯乙酮和尿素的三组分反应在N,N-二甲基甲酰胺(DMF)中制得4,6-二芳基-3,4-二氢嘧啶-2(1H)-酮类化合物,收率为68%～84%.若在反应体系中加入三甲基氯硅烷,该三组分反应则高产率(66%～87%)地生成相应的脱氢产物4,6-二芳基嘧啶-2(1H)-酮类化合物.该反应具有反应条件温和、产物收率高、操作方便等优点,为4,6-二芳基-嘧啶-2(1H)-酮类药物中间体的合成提供了一条全新的路线.     

三氯化铁催化的—锅法合成3,4-二氢嘧啶-2-酮

六水合三氯化铁催化下,β-酮酸酯、芳香醛、脲(1:1:1.5)在无水乙醇中进行环化缩合反应,合成了3,4-二氢嘧啶-2-酮衍生物,改进了Biginelli用盐酸为催化剂的一锅法反应,缩短了反应时间,操作简便,产率高达80％～90％,且Fe~(3 )对环境友好。     

Facile conversion of Biginelli 3,4-dihydropyrimidin-2(1H)-thiones to 2-(2-hydroxy-2-arylvinyl) dihydropyrimidines via Eschenmoser coupling

A one-pot, two-step synthesis protocol for the conversion of Biginelli 3,4-dihydropyrimidin-2(1H)-thiones to 2-(2-hydroxy-2-arylvinyl) dihydropyrimidine (DHPM) derivatives via Eschenmoser sulfide contraction coupling is described. Solution phase as well as solid-supported protocol was carried out for the decoration of the Biginelli DHMP scaffold at the C-2 position. The scope of the optimized protocol is demonstrated for different DHMP precursors.     

Heteropoly-12-tungstophosphoric acid H3[PW12O40] over natural bentonite as a heterogeneous catalyst for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones

Heteropolyacid 12-tungstophosphoric acid H₃[PW₁₂O₄₀] (TPA) immobilized over natural bentonite (bent) using the impregnation method. Prepared catalyst were well characterized by XRD, FT-IR and FeSEM. The catalytic activity of three catalysts 10%, 20% and 30% TPA/bent examined for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones known as Biginelli reaction. The catalyst 30% TPA/bent exhibited a high yield of the product towards the synthesis of a variety of dihydropyrimidones (DHPMs). The high yield of dihydropyrimidone (DHPM) was obtained in model reaction in ethanol, acetonitrile and solvent - free condition. The reusability test indicated that 5% of yield of product decreased after 5th cycle.     

Training the old dog new tricks: the applications of the Biginelli reaction in polymer chemistry

Recently, the Biginelli reaction, one of the most famous multicomponent reactions, has been introduced into the polymer chemistry to highly efficiently synthesize some interesting functional polymers. In this mini-review, several applications of the Biginelli reaction in polymer chemistry have been summarized, including polycondensation, post-polymerization modification, one-pot synthesis of well-defined polymer, etc. Meanwhile, the utilization of the Biginelli reaction in material science and chemical biology, and the future development of the Biginelli reaction in polymer chemistry have also been discussed.     

A new biginelli reaction procedure using potassium hydrogen sulfate as the promoter for an efficient synthesis of 3,4‐dihydropyrimidin‐2(1H)‐one

Simple and improved conditions have been found to carry out the Biginelli reaction for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐one derivatives. This synthesis was performed using potassium hydrogen sulfate as the promoter in ethylene glycol solution. Compared with the classical Biginelli reaction conditions, this new method has the advantage of excellent yields (85–95%) and short reaction time (0.5–2 h).     

3, 4-二氢嘧啶-2-酮衍生物合成研究进展

综述了近十年来3,4-二氢嘧啶-2-酮衍生物合成的研究进展,包括催化合成、固相合成、微波促进合成及天然产物合成中的一些最新研究进展。     

Magnetically reusable nanocatalysts in biginelli synthesis of dihydropyrimidinones (DHPMs)

Abstract

Molecules containing dihydropyrimidinone (DHPMs) structures are very important in pharmaceutical and medicinal chemistry due to their excellent biological activities application in synthesis of natural products. Biginelli condensation reaction between an aldehyde, urea/thiourea and a carbonyl compound is the most popular strategy for the synthesis of dihydropyrimidinones. Magnetic recoverable nanocatalysts can be readily separated from reaction medium by using an external magnet, without the need for filtration, centrifugation or other tedious workup processes. In recent times, the catalytic potential of magnetically recoverable nanocatalysts was evaluated in a variety of Biginelli reactions. In this review, we focus on the application of magnetically recoverable gold nanocatalysts in Biginelli synthesis of dihydropyrimidinone derivatives.     

An unusual oxidation-dealkylation of 3,4-dihydropyrimidin-2(1H)-ones mediated by Co(NO3)2·6H2O/K2S2O8 in aqueous acetonitrile

4-Aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one (DHPM) scaffolds of Biginelli type were oxidized using Co(II)/S₂O₈²⁻ and the reaction afforded 6-unsubstituted pyrimidin-2(1H)-ones through an unprecedented dealkylation process. 4-Alkyl DHPMs under similar conditions afforded yet another unusual product, ethyl tetrahydropyrimidin-2,4(1H,3H)-dione-5-carboxylate.     

Demonstration of the feasibility of a direct solid-phase split-pool Biginelli synthesis of 3,4-dihydropyrimidinones

[reaction: see text] A direct, Lewis acid-catalyzed Biginelli synthesis of 3,4-dihydropyrimidinones has been performed on high-capacity polystyrene macrobeads with a polymer O-silyl-attached N-(3-hydroxypropyl)urea. Resin-urea was first reacted separately with either 4-bromo- or 4-chlorobenzaldehyde and LiOTf in MeCN at 80 degrees C. After washing, the beads were pooled and reacted with ethyl acetoacetate and LiOTf in MeCN at 80 degrees C. Formation of only one kind of Biginelli product per bead demonstrated the feasibility of a solid-phase non-Atwal two-step split-and-pool synthesis of 3,4-dihydropyrimidinones.     

Efficient and Green Microwave-Assisted Multicomponent Biginelli Reaction for the Synthesis of Dihydropyrimidinones Catalyzed by Heteropolyanion-Based Ionic Liquids Under Solvent-Free Conditions

An efficient and green route for the synthesis of dihydropyrimidinones via microwave-assisted Biginelli reaction catalyzed by 3 mol% of heteropolyanion-based ionic liquids under solvent-free conditions has been reported. The practical reaction was found to be compatible with different structurally diverse substrates. Good to excellent yields, short reaction times, and operational simplicity are the main highlights of this protocol. Moreover, the heteropolyanion-based ionic liquids were easily reusable for this Biginelli reaction.     

An efficient synthesis of β-ketoesters via transesterification and its application in Biginelli reaction under solvent-free,catalyst-free conditions

A simple and efficient transesterification process for the synthesis of β-ketoester derivatives has been achieved by the reaction of methyl β-ketoester with higher alcohols at 110 °C under solvent-free, catalyst-free conditions and its application in synthesis of 3,4-dihydropyrimidin-2(1H)-ones C-5 ester derivatives via Biginelli reaction has been described.