Synthesis and spectral studies on some tetrahydrobenzoxanthen-11-ones: crystal and molecular structure of 9,9-dimethyl-12-(2-nitrophenyl)-8,9,10,12-tetrahydrobenzo[<Emphasis Type="Italic">a</Emphasis>]xanthen-11-one

A series of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones have been synthesized by the multicomponent reaction (MCR) of β-naphthol, aryl aldehydes, and dimedone by using BF₃:OEt₂ as a catalyst. The derived compounds have been analyzed by IR, NMR (1D and 2D), and mass spectra. The single crystal X-ray structural analysis of 9,9-dimethyl-12-(2-nitrophenyl)-8,9,10,12-tetrahydrobenzo[a]-xanthen-11-one evidences the envelope conformation of the cyclohexane ring and the pyran ring tends to adopt flattened-boat conformation.     

A new green approach for the synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one derivatives using task specific acidic ionic liquid[NMP]H_2PO_4

12-Aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one derivatives were synthesized by a convenient and environmentally benign procedure involving multicomponent condensation reactions of substituted aromatic aldehydes with 2,7-dihydroxynaphthalene/2-naphthols/2,6-dihydroxynaphthlene and cyclic 1,3-dicarbonyl compounds in task specific acidic ionic liquid[NMP]H_2PO_4 at 80 ℃.This protocol has proved to be efficient in terms of good yields,operational simplicity,easy workup,recyclability of reaction medium/catalyst,and short reaction time.     

An efficient one-pot synthesis of tetrahydrobenzo[a]xanthene-11-one and diazabenzo[a]anthracene-9,11-dione derivatives under solvent free condition

Indium(III) chloride catalyzed one-pot synthesis of 12-aryl/alkyl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one and 8,10-dimethyl-12-aryl-8,12-dihydro-7-oxa-8,10-diazabenzo[a]anthracene-9,11-dione derivatives have been achieved by three component cyclocondensation of aldehydes, β-naphthol and cyclic 1,3-dicarbonyl compounds under solvent free condition in high yields. P₂O₅ too has been found as an effective catalyst towards this transformation.     

A novel polymeric catalyst for the one-pot synthesis of xanthene derivatives under solvent-free conditions

A simple, efficient, and environmentally benign route was developed for the preparation of 14-aryl or alkyl-14H-dibenzo[a,j]xanthene, 1,8-dioxo-octahydroxanthene and 12-aryl??8,9,10,12-tetrahydrobenzo[a]xanthene-11-ones from condensation of various aldehydes with (i) ??-naphthol, (ii) cyclic 1,3-dicarbonyl compounds and (iii) ??-naphthol and cyclic 1,3-dicarbonyl compounds, using novel polymeric catalyst [poly(AMPS-co-AA)] under solvent-free conditions. Use of easily available catalyst, shorter reaction times, better yields, simplicity of the reaction, heterogeneous system, and easy work-up are the advantages of the present method.     

Efficient One-pot Synthesis of 12-Aryl-8, 9, 10, 12-tetrahydrobenzo[a]xanthen-11-ones Under Solvent-free Conditions

Multi-component condensation of 2-naphthol, aromatic aldehydes, and cyclic 1,3-dicarbonyl compounds catalyzed by ionic liquid [NSPTEA][HSO₄] was accomplished for the synthesis of a series of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones under solvent-free conditions. High yields, ease recovery, short reaction time and reusability of catalyst are significant advantages. ZrOCl₂·8H₂O was also found to act as an effective catalyst towards this transformation.     

pTSA-catalyzed one-pot synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones in ionic liquid and neat conditions

Multi-component condensation of β-naphthol, aromatic aldehydes, and cyclic 1,3-dicarbonyl compounds catalyzed by p-toluenesulfonic acid has been accomplished for the synthesis of a series of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones in ionic liquid([bmim]BF₄) and in solvent-free media. High yields, ease of recovery, and reusable reaction medium (ionic liquid) with consistent activity makes this protocol efficient and environmentally benign.     

Efficient and Green Syntheses of 12-Aryl-2,3,4,12-tetrahydrobenzo[b]xanthene-1,6,11-triones in Water and Task-Specific Ionic Liquid

Facile and convenient one-pot cascade/tandem approaches for the syntheses of privileged medicinal scaffolds, 12-aryl-2,3,4,12-tetrahydrobenzo[b]xanthene-1,6,11-trione derivatives, have been reported under extremely mild reaction conditions using a catalytic amount of H₂SO₄ in water or in the presence of the acidic ionic liquid bmim[HSO₄], which could be recycled.

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

Green Approaches for the Synthesis of 12-Aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones in Aqueous Media and Under Microwave Irradiation in Solventless Conditions

Convenient and environmentally benign procedures have been reported for the synthesis of 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one derivatives by multi component condensation reactions of aromatic aldehydes with β-naphthol and cyclic 1,3-dicarbonyl compounds, namely, dimedone and cyclohexane-1,3-dione. The three-component condensation has been successfully achieved in one pot by refluxing the components in water and is efficiently catalyzed by sulfuric acid. The condensation has also been achieved by irradiating the components in the presence of a catalytic amount of para-toluene sulfonic acid under neat conditions with microwaves. The green methodologies defined herein avoid the severe conditions posed by the older existing methods and prove to be efficient in terms of good yields, operational simplicity, easy workup, and short reaction time.     

New applications of cellulose-SO3H as a bio-supported and biodegradable catalyst for the one-pot synthesis of some three-component reactions

A bio-supported solid acid catalyst, cellulose-SO₃H, was used for three-component reactions to synthesize 2-amino-4-aryl-5-oxo-4H,5H-pyrano[3,2-c]chromene-3-carbonitriles, spirooxindoles, 2,3-dihydroquinazolin-4(1H)-ones, 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-ones, α-amidoalkyl-β-naphthols, and α-carbamato-alkyl-β-naphthols derivatives under solvent-free conditions.     

Synthesis and structure of 2-phenyl-4-aryl-3,4,5,6-tetrahydrobenzo[h]quinazolines

Summary The reaction of 2-arylidene-1-tetralones1 with benzamidine gave 2-phenyl-4-aryl-3,4,5,6-tetrahydrobenzo[h]quinazolines2. Investigations on the tautomeric equilibria of2 by IR,¹H- and¹³C-NMR showed the compounds to exist predominantly in the tautomeric form2A both in the solid state and in solution. Acetylation and oxidation of the heterocyclic ring of2 provided further evidence for the structural assignment of the title compounds.

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Synthese und Struktur von 2-Phenyl-4-aryl-3,4,5,6-tetrahydrobenzo[h]chinazolinen

Zusammenfassung Die Reaktion von 2-Aryliden-1-tetralonen1 mit Benzamidin ergab 2-Phenyl-4-aryl-3,4,5,6-tetrahydrobenzo[h]chinazoline2. Untersuchungen über das tautomere Gleichgewicht von2 mittels IR,¹H-NMR, und¹³C-NMR Spektroskopie zeigten, daß für die Verbindungen das Tautomere2A dominierte (sowohl in fester Phase als auch in Lösung). Acetylierung und Oxidation des heterocyclischen Ringes von2 ergab weitere Beweise für die Struktur der Titelverbindungen.

     

Efficient One-Pot Condensation of β-Naphthol,Aldehydes, and Cyclic 1,3-Dicarbonyl Compounds Catalyzed by p-TSA Under Solvent-Free and Sonication Conditions

A facile and efficient procedure has been developed by one-pot condensation of β-naphthol, aldehydes, and cyclic 1,3-dicarbonyl compounds for the synthesis of 8,9,10,12-tetrahydrobenzo[a]xanthen-11-one or 8,9-dihydrobenzo-[f]cyclopenta[b]chromen-10(11H)-one derivatives catalyzed by p-toluenesulfonic acid under solvent-free and sonication conditions.     

6,6-Heptamethylenetetrahydropyran-2,4-dione in the Synthesis of Benzo[f]pyrano[3,4-b]quinolines and Pyrano[4,3-b][4,7]phenanthrolines

Three-component condensation of 6,6-heptamethylenetetrahydropyran-2,4-dione with 2-amino-naphthalene or 6-aminoquinoline and aromatic aldehydes in an aliphatic alcohol afforded 12-aryl-9,9-hepta-methylene-8,9,10,12-tetrahydro-7H-benzo[f]pyrano[3,4-b]quinolin-11-ones and 12-aryl-9,9-heptamethylene-8,9,10,12-tetrahydro-7H-pyrano[4,3-b][4,7]phenanthrolin-11-ones, new N,O-heterocycles which include azaor diazaphenanthrene system fused to -pyrone ring and aromatic and spiro substituents.     

Iodine-Catalyzed Synthesis of 12-Aryl-8,9,10,12-tetrahydro-benzo[a]xanthen-11-one Derivatives via Multicomponent Reaction

Iodine efficiently catalyzes the one-pot, three-component reaction of aryl aldehyde, 2-naphthol, and cyclic 1,3-dicarbonyl compound under solvent-free conventional heating conditions to afford the corresponding 12-aryl-8,9,10,12-tetrahydro-benzo[a]xanthen-11-one derivatives. The present approach offers several advantages such as shorter reaction times, good yields, low cost, and mild reaction conditions.     

SYNTHESIS AND REACTIONS OF 2,3-DIHYDRO- 5-ARYL-5H,6H-THIAZOLO[3,2-b]-2,4-DIAZAFLUORENE-3,6-DIONES OF POTENTIAL BIOLOGICAL ACTIVITIES

Abstract

1,2,3,4-Tetrahydro-l-aryl-3,9-dioxo-2,4-diazafluorenes (2) and 1,2,3,4-tetrahydro-1-aryl-9-oxo-3-thi-oxo-2,4-diazafluorenes (3) were newly synthesized. Compounds 3 reacted with chloroacetic acid, α-bromopropanoic acid, or B-bromopropanoic acid in the presence of fused sodium acetate and acetic anhydride to give 2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (4), 2-methyl-2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (5) and 2,3-dihydro-6-aryl-6H,7H-thiazino[3,2-b]2,4-diazafluorene-4,7-diones (6), respectively.

2,3-Dihydro-2-arylmethylene-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (7) were prepared by the reaction of compounds (3) with chloroacetic acid and aromatic aldehydes in the presence of fused sodium acetate and acetic anhydride or by the reactions of (4) with aromatic aldehydes in the presence of acetic anhydride.

2-(Arylhydroazono)-5-aryl-2,3-dihydro-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (8) were synthesized by coupling (4) with aryldiazonium salts in the presence of pyridine.     

Oxidation of 4,7-phenanthroline derivatives

Oxidation of 1,3-diphenyl-4,7-phenanthroline with potassium permanganate in alkaline medium results in transformation of the 4,7-phenanthroline ring system into 1,8-diaazafluorenone. Oxidation of 12-aryl-and 12-aryl-9,9-dimethyl-8,9,10,12-tetrahydro-7H-benzo[b][4,7]phenanthrolin-11-ones (condensation products of 6-arylmethylene-aminoquinolines with 1,3-cyclohexanedione and dimedone) with sodium nitrite in acetic acid leads to 12-aryl-9,10-dihydro-8H-benzo[b][4,7]phenanthrolin-11-ones. 13-Aryl-7,13-dihydro-12H-indeno-[2,1-b][4,7]phenanthrolin-12-ones obtained by reaction of 6-arylmethyleneaminoquinolines with 1,3-indandione are oxidized to 13-aryl-12H-indeno[2,1-b][4,7]phenanthrolin-12-ones on heating in nitrobenzene.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004, pp. 1369–1375.Original Russian Text Copyright © 2004 by Gusak, Kozlov, Tereshko.     

A synthesis and biological screening of newly substituted 9-methyl-6-aryl-[1,2,4]triazolo[4,3-a][1,8]naphthyridines using chloranil

An effective, mild, and convenient method for the synthesis of 10 new substituted 9-methyl-6-aryl-[1,2,4]triazolo[4,3-a][1,8]naphthyridines (5a–j) by the oxidation of the corresponding 2-(2-ethylidenehydrazinyl)-3-aryl-1,8-naphthyridines (4a–j) using chloranil under conventional method has been described. The structures of synthesized compounds (5a–j) were established on the basis of their elemental analysis and spectral (IR, Mass, ¹³C- and¹H-NMR) data. The new compounds were synthesized with the objective of studying their antibacterial activity. The reaction will be characterized by easy workup, good efficacy, simple purification of the products, and availability of catalyst.     

Condensation of quinolin-6-amine with 5-(<Emphasis Type="Italic">p</Emphasis>-methoxyphenyl)-cyclohexane-1,3-dione and substituted benzaldehydes

New 12-aryl-9-(p-methoxyphenyl)-8,9,10,12-tetrahydro-7H-benzo[b][4,7]phenanthrolin-11-ones having two asymmetric carbon atoms (C⁹ and C¹²) were synthesized by three-component condensation of quinolin-6-amine with 5-(p-methoxyphenyl)cyclohexane-1,3-dione and substituted benzaldehydes. According to the ¹H NMR data, the products are mixtures of diastereoisomers.     

Synthesis,Antibacterial, and Antifungal Activities of Imidazo[2,1-c][1,2,4]triazoles and 1,2,4-Triazolo[4,3-a]pyrimidinones

A straightforward method has been developed for the synthesis of 1-phenyl-imidazo [2,1-c][1,2,4]triazole derivatives 5a–j and 1-phenyl-[1,2,4]triazolo[4,3-a]pyrimidinones derivatives 6a–g starting from 5-amino-1-phenyl[1,2,4]triazole and p-toluenesulfonic acid (PTSA). This methodology affords a number of 1-phenyl-imidazo [2,1-c][1,2,4]triazoles 5a–j and 1-phenyl-[1,2,4]triazolo[4,3-a]pyrimidinones 6a–g in reasonable yields and short reaction times. The structures of all new compounds were elucidated using infrared, ¹H and ¹³C NMR, and high-resolution mass spectrometry. Some of the newly synthesized compounds were screened for their antimicrobial activity.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications ^® for the following free supplemental resource(s): Full experimental and spectral details.]     

HClO4–SiO2-catalyzed synthesis of 12-aryl-12H-benzo[i][1,3]dioxolo[4,5-b]xanthene-6,11-diones and 10-aryl-6,7,8,10-tetrahydro-7,7-dimethyl-9H-[1,3]dioxolo[4,5-b]xanthen-9-ones

Abstract  

Three-component one-pot synthesis of some novel 12-aryl-12H-benzo[i][1,3]dioxolo[4,5-b]xanthene-6,11-diones involving treatment of 3,4-methylenedioxyphenol, aldehydes, and 2-hydroxy-1,4-naphthoquinone in presence of HClO₄–SiO₂ was achieved, and this reaction was extended to preparation of 10-aryl-6,7,8,10-tetrahydro-7,7-dimethyl-9H-[1,3]dioxolo[4,5-b]xanthen-9-ones by three-component reaction of 3,4-methylenedioxyphenol, aldehydes, and dimedone.     

Synthesis,Reactions, and Characterization of 6-Amino-4-(Benzo[b]Thiophen-2-YL)-2-Thioxo-1, 2-Dihydropyridine-3, 5-Dicarbonitrile

Abstract

Benzothiophene -2- carbaldehyde 1 reacted with 2-cyanoethanethioamide 2 in 1:2 molar ratios to give the corresponding 6-amino-4-(benzo[b]thiophen-2-yl)-2-thioxo-1, 2-dihydropyridine-3,5-dicarbonitrile 6. The synthetic potentiality of compound 6 was investigated via its reaction with active halogen-containing reagents to afford the corresponding thieno[2,3-b]pyridine derivatives 11a,b, 14, 16, and 19. Also, compound 6 reacted with hydrazine hydrate to give the pyrazolo[3,4-b]pyridine derivative 21. Compound 21 condensed with 4-(2-thienyl)benzaldehyde to afford pyrazolo[3,4-b]pyridine derivative 23. Structural elucidation of all the newly synthesized heterocyclic compounds was based on elemental analyses, IR, ¹H NMR, and mass spectra.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.