Improvement of Selectivity in the Fries Rearrangement and Direct Acylation Reactions by Means of P2O5/SiO2 under Microwave Irradiation in Solvent-Free Media.

ChemInform ◽  
2004 ◽  
Vol 35 (27) ◽  
Author(s):  
Hossein Eshghi ◽  
Mohammad Rafie ◽  
Zinat Gordi ◽  
Moosa Bohloli
Keyword(s):  
Microwave Irradiation ◽  
Solvent Free ◽  
Fries Rearrangement ◽  
Direct Acylation ◽  
Free Media ◽  
Acylation Reactions

scholarly journals Tandem Fries Reaction–Conjugate Addition under Microwave Irradiation in Dry Media; One-pot Synthesis of Flavanones

1999 ◽  
Vol 23 (9) ◽  
pp. 574-575
Author(s):  
Firouz Matloubi Moghaddam ◽  
Mohammad Ghaffarzadeh ◽  
Seyed Hossein Abdi-Oskoui
Keyword(s):  
Microwave Irradiation ◽  
Silica Gel ◽  
Conjugate Addition ◽  
Solvent Free ◽  
Naphthalene Derivatives ◽  
One Pot ◽  
Fries Rearrangement ◽  
One Pot Synthesis ◽  
Solvent Free Conditions ◽  
Fries Reaction

An AICl3–ZnCl2 mixture supported on silica gel is found to be an efficient medium for the Fries rearrangement of acyloxybenzene or naphthalene derivatives in solvent-free conditions under microwave irradiation.

scholarly journals K-10 clay as a reusable catalyst for the solvent-free MW-induced synthesis of enaminones

2014 ◽  
Vol 79 (8) ◽  
pp. 921-926 ◽  
Author(s):  
Omid Marvi ◽  
Masoud Giahi ◽  
Pouran Ayub ◽  
Mohammad Nikpasand
Keyword(s):  
Microwave Irradiation ◽  
Solvent Free ◽  
Reusable Catalyst ◽  
Dicarbonyl Compounds ◽  
Unsaturated Ketones ◽  
Acidic Catalyst ◽  
Free Media

A series of ?-amino-?, ?-unsaturated ketones and esters synthesized from the reaction of different amines with 1,3- dicarbonyl compounds in solvent-free media using montmorillonite K-10 clay as solid recyclable heterogeneous acidic catalyst and microwave irradiation in good to excellent yields.

scholarly journals Design of a New Gemini Lipoaminoacid with Immobilized Lipases Based on an Eco-Friendly Biosynthetic Process

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 164
Author(s):  
Patrícia M. Carvalho ◽  
Rita C. Guedes ◽  
Maria R. Bronze ◽  
Célia M. C. Faustino ◽  
Maria H. L. Ribeiro
Keyword(s):  
High Performance ◽  
Transfection Efficiency ◽  
Sol Gel ◽  
Reaction Rates ◽  
Solvent Free ◽  
Bioactive Molecules ◽  
Thermomyces Lanuginosus ◽  
Chemical Production ◽  
Immobilized Lipases ◽  
Free Media

Lipoaminoacids (LAA) are an important group of biosurfactants, formed by a polar hydrophilic part (amino acid) and a hydrophobic tail (lipid). The gemini LAA structures allow the formation of a supramolecular complex with bioactive molecules, like DNA, which provides them with good transfection efficiency. Since lipases are naturally involved in lipid and protein metabolism, they are an alternative to the chemical production of LAA, offering an eco-friendly biosynthetic process option. This work aimed to design the production of novel cystine derived gemini through a bioconversion system using immobilized lipases. Three lipases were used: porcine pancreatic lipase (PPL); lipase from Thermomyces lanuginosus (TLL); and lipase from Rizhomucor miehei (RML). PPL was immobilized in sol-gel lenses. L-cystine dihydrochloride and dodecylamine were used as substrates for the bioreaction. The production of LAA was evaluated by thin layer chromatography (TLC), and colorimetric reaction with eosin. The identification and quantification was carried out by High Performance Liquid Chromatographer-Mass Spectrometry (HPLC-MS/MS). The optimization of media design included co-solvent (methanol, dimethylsulfoxide), biphasic (n-hexane and 2-propanol) or solvent-free media, in order to improve the biocatalytic reaction rates and yields. Moreover, a new medium was tested where dodecylamine was melted and added to the cystine and to the biocatalyst, building a system of mainly undissolved substrates, leading to 5 mg/mL of LAA. Most of the volume turned into foam, which indicated the production of the biosurfactant. For the first time, the gemini derived cystine lipoaminoacid was produced, identified, and quantified in both co-solvent and solvent-free media, with the lipases PPL, RML, and TLL.

scholarly journals TMSOTf-catalyzed synthesis of trisubstituted imidazoles using hexamethyldisilazane as a nitrogen source under neat and microwave irradiation conditions

RSC Advances ◽  
2021 ◽  
Vol 11 (45) ◽  
pp. 28061-28071
Author(s):  
Kesatebrhan Haile Asressu ◽  
Chieh-Kai Chan ◽  
Cheng-Chung Wang
Keyword(s):  
Microwave Irradiation ◽  
Nitrogen Source ◽  
Microwave Heating ◽  
Solvent Free ◽  
Solvent Free Conditions

Trisubstituted imidazoles are synthesized efficiently from the readily available 1,2-diketones and aldehydes using hexamethyldisilazane as a new and stable nitrogen source under TMSOTf-catalysis system, microwave heating and solvent-free conditions.

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