Catalytic application of task specific ionic liquid on the synthesis of benzoquinazolinone derivatives by a multicomponent reaction

Benzoquinazolin-2-one derivatives were synthesized by using a catalytic amount of task specific ionic liquid, [1-methyl-3-(4-sulfobutyl)imidazolium-4-methylbenzenesulfonate] through a one-pot multicomponent Biginelli reaction of α-tetralone, aldehyde, and urea/thiourea in excellent yields within a short reaction time. Mechanism studies suggest that the reaction proceeds through iminium intermediate and C2-H of the TSIL plays a major role on its catalytic activity. The catalyst has been reused four times without any significant loss in catalytic activity. Large scale reaction by using this TSIL suggests the applicability of this methodology for bulk synthesis of quinazolinone derivatives.     

Biginelli reaction starting directly from alcohols

An efficient of one-pot oxidative access to 3,4-dihydropyrimidin-2-(1H)-ones directly from aromatic alcohols under mild conditions is reported. The protocol involves 1-methylimidazolium hydrogen sulphate [Hmim]HSO₄ catalyzed oxidation of aromatic alcohols to aromatic aldehydes with NaNO₃ followed by their cyclocondensation with 1,3-dicarbonyl compounds and urea in the same reaction vessel at 80 °C within 2-4 h to afford 3,4-dihydropyrimidin-2-(1H)-ones in 55-97% overall yields. Thus, the present work utilizing alcohols instead of aldehyde in Biginelli reaction is a valid and green alternative to the classical synthesis of 3,4-dihydropyrimidin-2-(1H)-ones.     

离子液体中微波促进的Biginelli缩合反应

在微波辐射下,以离子液体1-丁基-3-甲基咪唑四氟硼酸盐([bmim]BF4)为催化剂,三组分一锅法Bigi-nelli缩合反应快速地合成了10种高收率的5-乙氧羰基4-芳基二氢嘧啶酮衍生物的缩合产物,其结构经IR和^1H NMR确证。     

One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Catalyzed by Acidic Ionic Liquids Under Solvent-Free Conditions

The acidic ionic liquids were new catalysts for the one-pot Biginelli reaction coupling of aldehyde, 1,3-dicarbonyl compound, and urea to afford the corresponding dihydropyrimidinones in good yields under solvent-free conditions. The catalysts could be recycled and reused five times without a noticeable decrease in catalytic activity.     

Biginelli 3,4-二氢嘧啶-2-酮衍生物的合成研究新进展

1893年, 意大利化学家Biginelli首次利用芳香醛、乙酰乙酸乙酯和尿素三组分“一锅煮法”合成了3,4-二氢嘧啶-2(1H)-酮. 此类化合物具有良好的生物活性和反应活性, 对近几年来有关Biginelli 3,4-二氢嘧啶-2(1H)-酮的衍生化反应、Biginelli不对称合成和Biginelli反应在天然产物合成中的应用研究进行了综述.     

Concise synthesis of guanidine-containing heterocycles using the Biginelli reaction

Two general methods for the synthesis of 2-imino-5-carboxy-3,4-dihydropyrimidines were developed using the three-component Biginelli reaction. The first method utilizes pyrazole carboxamidine, a beta-ketoester, and an aldehyde in an initial Biginelli reaction. After Boc protection, these products undergo aminolysis and acidic deprotection to generate 2-imino-5-carboxy-3,4-dihydropyrimidines in a four-step sequence. The second method utilizes a triazone-protected guanidine, a beta-ketoester, and an aldehyde in a Biginelli reaction. Acidic cleavage of the triazone yields 2-imino-5-carboxy-3,4-dihydropyrimidines in a two-step sequence. We also describe the further elaboration of several of these products using a tethered Biginelli reaction to give triazaacenaphthalene structures similar to those found in crambescidin and batzelladine alkaloids.     

Advances in Biginelli reaction: A comprehensive review

The Biginelli reaction, a conventional three-component reaction provides 3,4-dihydropyrimidin-2(1H)-ones/thiones via one-pot acid catalyzed cyclocondensation of an aldehyde, a β-keto ester, and urea or thiourea. Dihydropyrimidones are well-known scaffolds having a wide range of pharmacological activities. So far classical Biginelli reaction has witnessed several modification and studies are still continuing in this field to develop greener and efficient methodologies. In this review, we summarize the recent advances in Biginelli reaction covering literature from 2020 to 2023.     

Diastereo- and enantioselective synthesis of oxazine and oxazolidine derivatives with a chiral quaternary carbon center under multifunctional catalysis

An easy one-pot, multistep cascade reaction which could afford a series of substituted benzo[d]pyrido[2,1-b]oxazolidine and [1,3]oxazine derivatives in a highly enantio- (up to 98% ee) and diastereoselective (4:1 to >20:1 dr) manner with generally good to excellent yields (up to 99%) has been developed. This well designed strategy could be applied to a wide scope of substrates under mild conditions with simple operations.     

Synthesis,reactions, and antimicrobial activity of some novel fused thiazolo[3,2-<Emphasis Type="Italic">a</Emphasis>]pyrimidine-5<Emphasis Type="Italic">H</Emphasis>-indeno[1,2-<Emphasis Type="Italic">d</Emphasis>]pyrimidine derivatives

Series of novel substituted thioxopyrimidine and thiazolo[3,2-a]pyrimidine compounds that combine various heteroaryl rings have been synthesized via Biginelli one-pot three-component reaction and elucidated with chemical and spectral analysis. Several products were tested for their antimicrobial properties.     

Refined methods for the synthesis of meso-substituted A3- and trans-A2B-corroles

We have refined a one-pot synthesis of A3-corroles via "3 + 4" condensation of an aldehyde with a pyrrole followed by macrocyclization mediated by DDQ. After thorough examination of various reaction parameters (reactivity of an aldehyde, catalyst, solvent, concentration, time etc.) we have elaborated three different sets of conditions for different types of aromatic aldehydes--highly reactive, moderately reactive and sterically hindered. Thanks to the identification of the key factors influencing the yield of bilanes and the yield of their conversion to corroles we were able to improve yields to ca. 17% for highly reactive aldehydes and ca. 13% for moderately reactive aldehydes. Altogether fourteen A3-corroles have been prepared in 7-21% yield. 5,10,15-Trimesitylcorrole has been obtained for the first time. [2 + 1] Condensation between sterically hindered dipyrromethanes and aldehydes has also been refined and yields of trans-A2B-corroles have been improved by ca. 10%.     

SYNTHESIS AND PROPERTIES OF TWO POLY(PHENYL METHACYLATE)S FUNCTIONALIZED WITH PEDENT DIHYDROPYRIMID(THI)ONE GROUPS

New polymers with functionalized dihydropyrimidones were synthesized.The methacryloyl chloride was first reacted with 4-hydroxybenzaldehyde,and the affording aldehyde was upon the one-pot Biginelli reaction to afford new monomers with dihydropyrimidone as pending groups (M1,M2).Two new monomers were polymerized via radical polymerization to afford interesting color changeable polymers in different pH.The polymers were characterized by ~1H-NMR and IR methods.The color changeable properties were also inves...     

Bismuth compounds in organic synthesis. A one-pot synthesis of homoallyl ethers and homoallyl acetates from aldehydes catalyzed by bismuth triflate

[reaction: see text] Three one-pot methods for the conversion of aldehydes to homoallyl ethers catalyzed by Bi(OTf)(3).xH(2)O (1 < x < 4) have been developed. The one-pot synthesis of homoallyl ethers can be achieved either by in situ generation of the acetal followed by its reaction with allyltrialkylsilane or by a three-component synthesis in which the aldehyde, trimethylorthoformate or an alkoxytrimethylsilane and allyltrimethylsilane are mixed together in the presence of bismuth triflate (0.1-1.0 mol %). In addition, a three-component synthesis of homoallyl acetates, which is achieved by reacting the aldehyde, acetic anhydride, and allyltrimethylsilane in the presence of bismuth triflate (3.0-5.0 mol %), has been developed. The use of a relatively nontoxic, easy to handle, and inexpensive catalyst adds to the versatility of these methods.     

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.     

Catalyst free synthesis of fused pyrido[2,3-d]pyrimidines and pyrazolo[3,4-b]pyridines in water

A one-pot,three-component condensation reaction of an aldehyde,benzoyl acetonitrile(3-oxo-3-phenylpropane nitrile) and 6- amino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione or 3-methyl-1-phenyl-1H-pyrazol-5-amine in water to give fused pyrido[2,3- d]pyrimidines and pyrazolo[3,4-b]pyridines in high yields without any catalyst,is described.     

One-pot Copper Nanoparticle-catalyzed Synthesis of Imidazo[1,2-α]pyridines Under Solvent-free Conditions

A direct and efficient approach to synthesize imidazo[1,2-α]pyridines through three-component one-pot reaction of 2-aminopyridine,aldehyde and terminal alkyne catalyzed by Cu-nanoparticles under solvent-free conditions has been developed.This method provides a rapid access to substituted imidazo[1,2-α]pyridines with good yields（up to 85％）.     

Synthesis of environmentally friendly,magnetic acid-type calix[4]arene catalyst for obtaining Biginelli adducts

An immobilized p-sulfonic acid calix[4]arene was synthesized on the surface of silica-coated Fe₃O₄ nanoparticles. Due to the combination of the magnetic recovery and the acid properties, it acted as a robust, safe and environmentally friendly catalyst for the one-pot synthesis of Biginelli adducts under microwave irradiation and solvent-free conditions. A series of Biginelli adducts were obtained in moderate to excellent yields, and most importantly, the catalyst could be easily recovered by an external magnet and reused five times without significant loss of catalytic activity (ca. 80% yield for all reuses using 0.64 mol% of the catalyst).     

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.     

INVESTIGATION OF THE EFFECTS OF SOME HEAT SINKS IN MICROWAVE-ASSISTED SYNTHESIS OF SOME BIGINELLI COMPOUNDS

Pyrimidine derivatives 4a–ewere synthesized by Biginelli reaction under microwave irradiation. The effectiveness of different baths or containers including ceramic, silica gel, potsherd, alumina, and molecular sieve as heat sinks in mediating the microwave irradiation for the formation of 4a–ehas been investigated. All one-pot condensations of β -Ketoester 1, aryl aldehyde 2, and (thio)urea 3in heat sinks provide high yields of the desired compounds, particularly when reactions are run at low temperature. In addition, we found that potsherd and ceramic are suitable heat sinks for preparation of these cyclocondensation products under microwave irradiation.     

Efficient one-pot synthesis of 1,3-diaryl-3H-benzo[f]chromenes using ferric hydrogensulfate

<正>An efficient and easy method for one-pot three-component synthesis of l,3-disubstituted-3H-benzo[f]chromenes by the condensation of naphtol,aromatic aldehyde derivatives and phenylacetylene in the presence of ferric hydrogensulfate[Fe(HSO_4)_3], has been described.The catalyst displayed high activity which afforded the corresponding 1,3-disubstituted-3H-benzo[f]chromenes in satisfying yields.Alkyl-substituted phenols were examined and the corresponding benzopyran derivatives were synthesized in moderate yields.Heterogeneous nature of the using catalyst made it reusable for further chemical reactions.     

A convenient one-pot synthesis of new chromeno[3,4-c]chromene and chromeno[3,4-c]pyridine derivatives in the presence of high surface area of magnesium oxide

In this investigation a new strategy involves the one-pot,three-component reaction of malononitrile,salycilaldehyde and phenol derivatives in the presence of high surface area of MgO is extended to the formation of chromeno[3,4-c]chromene derivatives in good to excellent yields in a short reaction time.Also,the three component reactions of an aldehyde such as salycilaldehyde and ketones with malononitril for the formation of chromeno[3,4-c]pyridines are investigated.