DABCO Promoted Regioselective Synthesis of New Diversely Functionalized 3-Hydroxy-2-Oxindole Scaffolds

2014 ◽  
Vol 67 (5) ◽  
pp. 768 ◽  
Author(s):  
Pramod B. Thakur ◽  
Jagdeesh B. Nanubolu ◽  
Harshadas M. Meshram
Keyword(s):  
Catalytic Amount ◽  
Regioselective Synthesis ◽  
Reaction Conditions ◽  
Metal Free ◽  
Structural Framework

An efficient and highly regioselective γ-addition of β-keto sulfones on isatins has been achieved in the presence of a catalytic amount of 1,4-diazabicyclo[2.2.2]octane (DABCO) to afford a γ-(3-hydroxy-2-oxindole)-β-keto sulfone structural framework. The scope of the method is tested by screening a series of isatin electrophiles as well as β-keto sulfones. The described method was found to be very handy and provides straightforward access for the diversely functionalized 3-β-keto sulfone substituted-3-hydroxy-2-oxindole structural scaffolds in very good yields from readily available starting materials under metal-free reaction conditions.

scholarly journals Morpholin-2-one Derivatives via Intramolecular Acid-Catalyzed Hydroamination

Synthesis ◽  
2019 ◽  
Vol 51 (07) ◽  
pp. 1643-1648 ◽  
Author(s):  
David Knight ◽  
Thomas Wirth ◽  
Abdul Hadi Aldmairi
Keyword(s):  
Amino Acids ◽  
Catalytic Amount ◽  
Practical Method ◽  
Trifluoromethanesulfonic Acid ◽  
Reaction Conditions ◽  
Available N ◽  
Metal Free ◽  
Acid Catalyzed

Substituted morpholin-2-one derivatives were readily obtained in two steps starting from commercially available N-protected amino acids. In a metal-free and practical method, a catalytic amount of trifluoromethanesulfonic acid was sufficient to generate morpholinones under mild reaction conditions in an intramolecular hydroamination reaction in good to excellent yields.

A General Method for the Synthesis of 11H-indeno[1,2-b]quinoxalin-11-ones and 6H-indeno[1,2-b]pyrido[3,2-e]pyrazin-6-one Derivatives using Mandelic Acid as an Efficient Organo-catalyst at Room Temperature

2021 ◽  
Vol 08 ◽  
Author(s):  
Aditi Sharma ◽  
Gurpreet Kaur ◽  
Diksha Singh ◽  
Vivek Kumar Gupta ◽  
Bubun Banerjee
Keyword(s):  
Mandelic Acid ◽  
Room Temperature ◽  
Aqueous Ethanol ◽  
Low Cost ◽  
Catalytic Amount ◽  
Reaction Conditions ◽  
Metal Free ◽  
Naturally Occurring ◽  
Column Chromatographic ◽  
General Method

Aims: Synthesis of 11H-indeno[1,2-b]quinoxalin-11-ones as well as 6H-indeno[1,2-b]pyrido[3,2-e]pyrazin-6-one derivatives under greener conditions. Background: Quinoxaline and related skeletons are very common in naturally occurring bioactive compounds. Objective: Design a facile, green and organo-catalyzed method for the synthesis of 11H-indeno[1,2-b]quinoxalin-11-ones as well as 6H-indeno[1,2-b]pyrido[3,2-e]pyrazin-6-one derivatives. Methods: Both the scaffolds were synthesized via the condensation of ninhydrin and o-phenylenediamines or pyridine-2,3-diamines respectively by using a catalytic amount of mandelic acid as an efficient, commercially available, low cost, organo-catalyst in aqueous ethanol at room temperature. Results: Mild reaction conditions, use of metal-free organocatalyst, non-toxic solvent, ambient temperature, and no column chromatographic separation are some of the notable advantages of our developed protocol. Conclusion: In conclusion, we have developed a simple, mild, facile and efficient method for the synthesis of structurally diverse 11H-indeno[1,2-b]quinoxalin-11-one derivatives via the condensation reactions of ninhydrin and various substituted benzene-1,2-diamines using a catalytic amount of mandelic acid as a commercially available metal-free organo-catalyst in aqueous ethanol at room temperature. Under the same optimized reaction conditions, synthesis of 6H-indeno[1,2-b]pyrido[3,2-e]pyrazin-6-one derivatives was also accomplished with excellent yields by using pyridine-2,3-diamines instead of o-phenylenediamine.

p-Sulfonic acid calix[n]arene catalyzed synthesis of bioactive heterocycles: A review

2020 ◽  
Vol 24 ◽  
Author(s):  
Bubun Banerjee ◽  
Gurpreet Kaur ◽  
Navdeep Kaur
Keyword(s):  
Supramolecular Chemistry ◽  
Sulfonic Acid ◽  
Catalytic Efficiency ◽  
The Other ◽  
Reaction Conditions ◽  
Metal Free ◽  
Bioactive Scaffolds ◽  
Wide Range ◽  
Efficient Alternative ◽  
Bioactive Heterocycles

: Metal-free organocatalysts are becoming an important tool for the sustainable developments of various bioactive heterocycles. On the other hand, during last two decades, calix[n]arenes have been gaining considerable attention due to their wide range of applicability in the field of supramolecular chemistry. Recently, sulfonic acid functionalized calix[n] arenes are being employed as an efficient alternative catalyst for the synthesis of various bioactive scaffolds. In this review we have summarized the catalytic efficiency of p-sulfonic acid calix[n]arenes for the synthesis of diverse biologically promising scaffolds under various reaction conditions. There is no such review available in the literature showing the catalytic applicability of p-sulfonic acid calix[n]arenes. Therefore, we strongly believe that this review will surely attract those researchers who are interested about this fascinating organocatalyst.

Synthesis of Pyrrolo[1,2-a][1,6]- and [1,8]naphthyridines by Alkyne-Carbonyl Metathesis

Synthesis ◽  
2020 ◽  
Author(s):  
Peter Ehlers ◽  
Peter Langer ◽  
Marian Blanco Ponce ◽  
Silvio Parpart ◽  
Alexander Villinger ◽  
...  
Keyword(s):  
Heterocyclic Compounds ◽  
Metathesis Reaction ◽  
Synthetic Methodology ◽  
Facile Synthesis ◽  
Reaction Conditions ◽  
One Pot ◽  
Metal Free ◽  
Modular Synthesis

AbstractA concise and modular synthesis of pyrrolo[1,2-a][1,6]- and [1,8]naphthyridines by a one-pot two-step reaction consisting of electrophilic acylation followed by an alkyne-carbonyl-metathesis reaction as the final cyclization step is reported. This developed synthetic methodology allows the facile synthesis of these heterocyclic core structures in mainly high overall yields under metal-free conditions. Reaction conditions are carefully optimized and display a novel supplement to access these tricyclic heterocyclic compounds.

Chlorination of Arylaldehyde-Derived Arylsulfonylhydrazones with N-Chlorosuccinimide Leading to 1,2,4,5-Tetrazine Derivatives

Synthesis ◽  
2019 ◽  
Vol 52 (01) ◽  
pp. 69-74
Author(s):  
Yuan-Zhao Ji ◽  
Hui-Jing Li ◽  
Ying Liu ◽  
Yan-Chao Wu
Keyword(s):  
Potassium Hydroxide ◽  
Reaction Conditions ◽  
Metal Free ◽  
Vinyl Halides

It has been reported previously that treatment of aryl­ketone-derived arylsulfonylhydrazones with NXS/(nBu)4NX affords exclusively vinyl halides. In contrast, we have found that treatment of aryl­aldehyde-derived arylsulfonylhydrazones with N-chlorosuccinimide in the presence of potassium hydroxide affords 1,2,4,5-tetrazine derivatives in good to excellent yields. The present reactions are carried out under metal-free and mild reaction conditions.

Deadly KCN and pricey metal free track for accessing β-ketonitriles employing mild reaction conditions

2021 ◽  
pp. 1-10
Author(s):  
Pawan K. Sharma ◽  
Rajiv Kumar ◽  
Sita Ram ◽  
Navneet Chandak
Keyword(s):  
Reaction Conditions ◽  
Metal Free

Green synthesis of benzoimidazopyrimidine, benzimidazoloquinazolinone, triazolopyrimidine and triazoloquinazolinone derivatives catalyzed by oxalic acid dihydrate

2021 ◽  
Vol 18 ◽  
Author(s):  
Seyed Sajad Sajadikhah ◽  
Bagher Liravi-Deylami
Keyword(s):  
Oxalic Acid ◽  
Green Synthesis ◽  
Column Chromatography ◽  
Catalytic Amount ◽  
Atom Economy ◽  
One Pot ◽  
Oxalic Acid Dihydrate ◽  
Metal Free ◽  
Solvent Free Conditions ◽  
Simple Filtration

: Benzoimidazopyrimidine, benzimidazoloquinazolinone, triazolopyrimidine, and triazoloquinazolinone derivatives were synthesized via a one-pot multi-component reaction in the presence of a catalytic amount of oxalic acid dihydrate. The reactions were performed in the mixture of EtOH: H2O or under solvent-free conditions as green media. The advantageous features of these methodologies are inexpensive starting materials and catalyst, high atom economy and good yields, and metal-free synthesis. Moreover, all the products were obtained by simple filtration with no need for column chromatography or tedious separation procedures, which is very important in terms of reducing environmental pollutions.

Iodine-mediated C–N and C–S bond formation: regioselective synthesis of benzo[4,5]imidazo[2,1-b]thiazoles

2017 ◽  
Vol 41 (1) ◽  
pp. 75-80 ◽  
Author(s):  
Sethurajan Ambethkar ◽  
Muthalu Vellimalai ◽  
Vediappen Padmini ◽  
Nattamai Bhuvanesh
Keyword(s):  
Reaction Time ◽  
Intramolecular Cyclization ◽  
Simple Procedure ◽  
Bond Formation ◽  
Molecular Iodine ◽  
Regioselective Synthesis ◽  
Thiazole Derivatives ◽  
Short Reaction Time ◽  
Metal Free

The regioselective synthesis of benzo[4,5]imidazo[2,1-b]thiazole derivatives via amination (C–N) and intramolecular cyclization (C–S) reactions in the presence of molecular iodine has been reported. This method is base and metal free and features inexpensive catalysts, with a simple procedure and a short reaction time.

scholarly journals One-Pot and Metal-Free Synthesis of 3-Arylated 4-Nitrophenols via Polyfunctionalized Cyclohexanones from β-Nitrostyrenes

2020 ◽  
Author(s):  
Haruyasu Asahara ◽  
Minami Hiraishi ◽  
Nagatoshi Nishiwaki
Keyword(s):  
Dimethyl Sulfoxide ◽  
Catalytic Amount ◽  
Alder Reaction ◽  
Diels Alder ◽  
One Pot ◽  
Metal Free ◽  
Diels Alder Reaction ◽  
Thienyl Group ◽  
Danishefsky's Diene

β-Nitrostyrenes underwent the Diels-Alder reaction with Danishefsky’s diene to afford cyclohexenes together with the corresponding hydrolyzed products, 3-arylated 5-methoxy-4-nitrocyclohexanones. When the reaction was conducted in the presence of water, the cyclohexenes were efficiently hydrolyzed into cyclohexanones. Subsequent aromatization by heating the cyclohexanone with a catalytic amount of iodine in dimethyl sulfoxide gave 3-arylated 4-nitrophenols. The reaction of nitrostyrenes with Danishefsky’s diene could be conducted in one-pot to directly afford the corresponding nitrophenols. Moreover, a heteroaryl group such as a thienyl group could be introduced into the nitrophenol framework.

An efficient multicomponent, one-pot synthesis of Betti bases catalyzed by cerium (IV) ammonium nitrate (CAN) at ambient temperature

2016 ◽  
Vol 5 (4) ◽  
Author(s):  
Ramadan Ahmed Mekheimer ◽  
Abdullah Mohamed Asiri ◽  
Afaf Mohamed Abdel Hameed ◽  
Reham R. Awed ◽  
Kamal Usef Sadek
Keyword(s):  
Ambient Temperature ◽  
Environmental Pollution ◽  
Ammonium Nitrate ◽  
Room Temperature ◽  
Catalytic Amount ◽  
High Yield ◽  
Reaction Conditions ◽  
One Pot ◽  
Work Up ◽  
Cerium Iv Ammonium Nitrate

AbstractStarting from readily available 2-naphthol, aldehydes, aryl and alkylamines, a variety of Betti bases were efficiently synthesized utilizing a catalytic amount of cerium (IV) ammonium nitrate (CAN) at room temperature. This protocol has advantages of high yield, mild reaction conditions, no environmental pollution, diversity of reactants and simple work up procedure.

Sign in / Sign up

Export Citation Format

Share Document