Three-component Condensation Of Aromatic Aldehydes Research Articles

ChemInform Abstract: Michael Initiated Ring Closure (MIRC) Reaction on in situ Generated Benzylidenecyclohexane‐1,3‐diones for the Construction of Chromeno[3,4‐b]quinoline Derivatives.

Abstract One-pot synthesis of chromeno[3,4-b]quinoline derivatives have been achieved in good yields through Michael Initiated Ring Closure (MIRC) by employing three-component condensation of aromatic aldehydes, 3-aminocoumarins, and cyclic 1,3-diketones in the presence of catalytic amount of p-toluenesulfonic (p-TSA) acid in ethanol under reflux condition. The salient features of this protocol are: simple reaction procedure, shorter reaction time, good yields, avoidance of aqueous work-up, and column-chromatographic separation. The merit of this process is highlighted by its high bond efficiency of producing three new bonds and one stereocenter in a single operation.

Efficient Synthesis of 12-Aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one Derivatives Catalyzed by p-Dodecylbenzenesulfonic Acid in Aqueous Media Under Ultrasound Irradiation

An efficient synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one derivatives via the three-component condensation of aromatic aldehyde, 2-naphthol, and 5,5-dimethyl-1,3-cyclohexanedione was carried out in 76–93% yields at 40–42 °C using p-dodecylbenzenesulfonic acid as catalyst in aqueous media under ultrasound irradiation.

Brønsted acid ionic liquid [Et3NH][HSO4] as an efficient and reusable catalyst for the synthesis of 2,4,5-triaryl-1H-imidazoles

A simple and efficient procedure for synthesis of 2,4,5-triaryl-1H-imidazoles by one-pot three-component condensation of aromatic aldehydes, benzil and ammonium acetate under solvent-free conditions using ionic liquid [Et3NH][HSO4] as catalyst is described. The remarkable features of this procedure are high yields, cleaner reaction profiles, use of non-toxic, easily available, cheap, recyclable catalyst, which also has an environmentally benign nature, and simple experimental and work-up procedures.

Ultrasonic-Promoted One-Pot Synthesis of 4H-chromenes, pyrano[2,3- d]pyrimidines, and 4H-pyrano[2,3-c]pyrazoles

A facile and versatile procedure has been explored for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4Hchromenes, pyrano[2,3-d]pyrimidines and 1,4-dihydropyrano[2,3-c]pyrazole-5-yl cyanides. This protocol employs the one-pot three-component condensation of aromatic aldehydes and malononitrile with 5,5-dimethyl-cyclohexane-1,3- dione, 1,3-dimethyl barbituric acid or 3-methyl-1-phenyl-2-pyrazolin-5-ones respectively in ethanol under the catalytic effect of triethylamine and ultrasonic-irradiation conditions. Simple manipulation, high reaction rates, improved yields, use of inexpensive and non-toxic catalyst, and also use of ethanol as a relatively environmentally benign solvent are the main advantages of this protocol. Keywords: 4H-chromenes, pyrano[2, 3-d]pyrimidines, pyrano[2, 3-c]pyrazole, ultrasonic-irradiation, triethylamine, scaffolds, antibronchitics, microwave, electrochemically, induced

New example of acyl cleavage of benzoyl-1,1,1-trifluoroacetone in a three-component synthesis of 4-aryl-2-thioxo-6-phenyl-1,2-dihydropyridine-3-carbonitriles

A three-component condensation of aromatic aldehydes, cyanothioacetamide, and benzoyl-1,1,1-trifluoroacetone, involving the acyl cleavage of the latter, results in 4-aryl-2-thioxo-6-phenyl-1,2-dihydropyridine-3-carbonitriles. Their alkylation was studied.

ChemInform Abstract: Synthesis of 4‐Aryl‐6‐phenyl‐2‐thioxo‐1,2‐dihydropyridine‐3‐carbonitriles by Three‐Component Condensation of Aromatic Aldehydes with Cyanothioacetamide and 4,4,4‐Trifluoro‐1‐phenylbutane‐1,3‐dione.

4-Aryl-6-phenyl-2-thioxo-1,2-dihydropyridine-3-carbonitriles were synthesized by three-component condensation of aromatic aldehydes with cyanothioacetamide and 4,4,4-trifluoro-1-phenylbutane-1,3-dione. The reaction involved initial formation of Michael adducts which underwent acyl cleavage.

ChemInform Abstract: An Improved Procedure for the Three‐Component Synthesis of Benzo[g]chromene Derivatives Using Basic Ionic Liquid.

A basic ionic liquid, 1-butyl-3-methyl imidazolium hydroxide ([bmim]OH), efficiently promotes a one-pot, three-component condensation of aromatic aldehydes, malononitrile or ethyl cyanoacetate, and 2-hydroxy-1,4-naphthoquinone to produce 4-aryl-5,10-dihydro-4H-benzo[g]chromene-5,10-dione derivatives in high yields at room temperature. This reaction does not involve any hazardous organic solvent and toxic catalyst. The ionic liquid is recovered and recycled for subsequent reactions. Moreover, this protocol has the advantages of easy work-up, short reaction time, high yields, and environmentally benign procedure compared with the reported methods. J. Heterocyclic Chem., (2011).

Michael Initiated Ring Closure (MIRC) reaction on in situ generated benzylidenecyclohexane-1,3-diones for the construction of chromeno[3,4-b]quinoline derivatives

One-pot synthesis of chromeno[3,4-b]quinoline derivatives have been achieved in good yields through Michael Initiated Ring Closure (MIRC) by employing three-component condensation of aromatic aldehydes, 3-aminocoumarins, and cyclic 1,3-diketones in the presence of catalytic amount of p-toluenesulfonic (p-TSA) acid in ethanol under reflux condition. The salient features of this protocol are: simple reaction procedure, shorter reaction time, good yields, avoidance of aqueous work-up, and column-chromatographic separation. The merit of this process is highlighted by its high bond efficiency of producing three new bonds and one stereocenter in a single operation.

Synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one Catalyzed by Silica Sulfuric Acid Under Solvent Free Condition

An efficient synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one derivatives via the three-component condensation of aromatic aldehyde, 2-naphthol and 5,5-dimethyl-1,3-cyclohexanedione was carried out in 72- 85% yields at 80 °C under solvent free condition using silica sulfuric acid (SSA) as catalyst.

Synthesis of 4-aryl-6-phenyl-2-thioxo-1,2-dihydropyridine-3-carbonitriles by three-component condensation of aromatic aldehydes with cyanothioacetamide and 4,4,4-trifluoro-1-phenylbutane-1,3-dione

4-Aryl-6-phenyl-2-thioxo-1,2-dihydropyridine-3-carbonitriles were synthesized by three-component condensation of aromatic aldehydes with cyanothioacetamide and 4,4,4-trifluoro-1-phenylbutane-1,3-dione. The reaction involved initial formation of Michael adducts which underwent acyl cleavage.

Silica Gel을 이용한 효율적인 3,4-dihydropyrano[c]chromenes의 합성

실온에서 방향족 알데히드, 말론니트릴과4-히드록시쿠마린을neat 실리카젤 속에서 one-pot반응시켜서 3,4-dihydropyrano[c]chromenes을 좋은 수율로 합성하였다. Highly efficient, three-component condensation of aromatic aldehyde, malononitrile and 4-hydroxycoumarin promoted by neat silica gel at room temperature is described. The method offers an excellent alternative to the synthesis of 3,4-dihydropyrano[c]chromenes. The reactions are fast and clean, and the products are obtained with good yield and purity.

Synthesis of some oxa- and thiazolidine-1,3-diones and their oxiranyl and thiiranyl derivatives

Thiazolidinones (IV) and (VII), thiazolidinediones (V), and imidazolidinediones (IX) are synthesized in one step by three-component condensation of aromatic aldehydes or amines with chloroacetic acid and thiourea or urea.

Synthesis of 3,4-Dihydropyrano(c)Chromene Derivatives Using Sulfonic Acid Functionalized Silica (SiO 2 PrSO 3 H)

chromene derivatives were synthesized using sulfonic acid functionalized silica (SiO 2-Pr-SO 3H) as a highly efficient heterogenous solid acid catalyst via one-pot three-component condensation of aromatic aldehydes with malononitrile and 4-hydroxycoumarin in excellent yields.

ChemInform Abstract: Regio and Diastereoselective Synthesis of Functionalized 2,3‐Dihydrofuro[3,2‐c]coumarins via a One‐Pot Three‐Component Reaction.

Abstract An efficient and straightforward synthesis of furo[3,2-c]coumarins via the one-pot three-component condensation of aromatic aldehydes, 4-hydroxycoumarin and α-chloroketones in refluxing n-propanol is described. Pyridine or a mixture of AcOH and AcONH4 was used as a basic catalyst.

α-Fe2O3 nanoparticles: An efficient, inexpensive catalyst for the one-pot preparation of 3,4-dihydropyrano[c]chromenes

This paper describes the combustion synthesis of α-Fe2O3 nanopowder at much lower temperature and its catalytic activity for the one-pot preparation of 3,4-dihydropyrano[c]chromenes. The combustion derived α-Fe2O3 nanopowder was characterized by powder X-ray diffraction (PXRD), Braunauer, Emmett and Teller (BET) surface area, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Highly efficient, three-component condensation of aromatic aldehyde, malanonitrile and 4-hydroxycoumarin catalyzed by α-Fe2O3 nanoparticles at room temperature is described. The method offers an excellent alternative to the synthesis of 3,4-dihydropyrano[c]chromenes. The reactions are rapid, clean, and the products with good yield and high purity.

Regio and diastereoselective synthesis of functionalized 2,3-dihydrofuro[3,2-c]coumarins via a one-pot three-component reaction

An efficient and straightforward synthesis of furo[3,2-c]coumarins via the one-pot three-component condensation of aromatic aldehydes, 4-hydroxycoumarin and α-chloroketones in refluxing n-propanol is described. Pyridine or a mixture of AcOH and AcONH4 was used as a basic catalyst.

Three-component synthesis of some 2-amino-5-hydroxy-[1,2,4]triazolo[1,5-a]pyrimidine-6-carbonitriles and 2-(cyanoamino)-4-hydroxypyrimidine-5-carbonitriles

Nine new 2-amino-5-hydroxy-[1,2,4]triazolo[1,5-a]pyrimidine-6-carbonitriles and eight 2-(cyanoamino)-4-hydroxypyrimidine-5-carbonitriles have been synthesized in a simple and convenient method by three-component condensation of aromatic aldehydes, ethyl cyanoacetate, and 3,5-diamino-1,2,4-triazole or cyanoguanidine hydrochloride in alkaline ethanol. All new synthesized compounds were characterized by nuclear magnetic resonance (NMR), infrared (IR), ultraviolet (UV), mass spectrometry (MS), and elemental analyses.

Cost-effective ionic liquid for environmentally friendly synthesis of 3,4-dihydropyrimidin-2(1H)-ones

A simple, efficient and environmentally friendly process for synthesis of 3,4-dihydropyrimidinones using a one-pot three-component condensation of aromatic aldehydes, β-dicarbonyl compounds, and urea/thiourea is discussed. The cost-effective, new generation ionic liquid (IL), tri-(2-hydroxyethyl) ammonium acetate was used as both solvent and catalyst. The reactions were carried out using both conventional heating and microwave energy. Application of IL technology with microwave energy represents an attractive and rapid alternative to the conventional acid–base catalyzed thermal processes.

Synthesis of N,N-dimethyl(diethyl)-7-aryl-5-methyl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-6-carboxamides

It is known that N,N-dimethyl-3-oxobutanamide reacts with aromatic aldehydes in the presence of piperidine to give N,N,N′,N′,6-pentamethyl-2-aryl-6hydroxy-4-oxocyclohexane-1,3-dicarboxamides [1]. Zhidovinova et al. [2] described three-component condensation of ethyl 3-oxobutanoate with aromatic aldehydes and 5-aminotetrazole, which led to the formation of dihydrotetrazolopyrimidines [2]. While continuing studies in this line, we examined for the first time three-component condensation of aromatic aldehydes with 5-aminotetrazole and such substrates as N,N-dimethyland N,N-diethyl-3-oxobutanamides with a view to obtain new fused heterocyclic systems. The reactions occurred at 120–150°C in 20– 60 min, and the products were the corresponding N,N-dimethyland N,N-diethyl-7-aryl-5-methyl-4,7dihydrotetrazolo[1,5-a]pyrimidine-6-carboxamides Ia, Ib, and IIa–IId. These compounds were isolated as colorless crystalline substances which are soluble in chloroform, DMF, and DMSO and insoluble in water. The IR spectra of Ia, Ib, and IIa–IId contained absorption bands due to stretching vibrations of the amide carbonyl group (1660–1680 cm), NH group (3150–3200 cm), and C=C bonds (1600–1620 cm). In the H NMR spectra of Ia, Ib, and IIa–IId, protons in the 5-methyl group resonated as a singlet at δ 1.80– 1.90 ppm, the 7-H proton gave a singlet at δ 6.30– 6.65 ppm, and signal from the NH proton appeared as δ 10.30–10.50 ppm; also signals from aromatic protons were present. Signals from protons in the N-alkyl group were located at δ 2.70 ppm (s, CH3; Ia, Ib) or at δ 0.75-0.90 (m, CH3) and 3.05–3.10 ppm (m, CH2; IIa–IId). Compound Ib displayed in the mass spectrum [M – CO] ion peak with m/z 301 and peaks from fragment ions [M – CONMe2] (m/z 260), [M – NMe2] (m/z 285), and [Ph] (m/z 77) in support of the assumed structure.

Proline-Catalyzed Simple and Efficient Synthesis of 1,8-Dioxo-decahydroacridines in Aqueous Ethanol Medium

Proline-catalyzed synthesis of 1,8-dioxo-decahydroacridines is achieved via one-pot, three-component condensation of aromatic aldehydes, cyclic diketone, and aryl amines in aqueous ethanol medium. This method offers the advantages of proceeding in neutral and mild conditions, giving high to excellent yields of acridines with easy workup procedure.