Organic syntheses by microwave selective heating of novel metal/CMC catalysts – The Suzuki–Miyaura coupling reaction in toluene and the dehydrogenation of tetralin in solvent-free media

2012 ◽  
Vol 289 ◽  
pp. 266-271 ◽  
Author(s):  
Satoshi Horikoshi ◽  
Yindee Suttisawat ◽  
Atsushi Osawa ◽  
Chiemi Takayama ◽  
Xiuqin Chen ◽  
...  
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

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.


2020 ◽  
Vol 65 (10) ◽  
pp. 61-66
Author(s):  
Trang Nguyen Thi Minh ◽  
Trang Tran Thi Thu ◽  
Hoan Duong Quoc

Salicylic aldehydes, amine, and phenyl acetylene could react under the solvent-free, metal-free conditions to form propargylamines 1-4 via A3 coupling reaction. The yield of the reaction was up to 83% for 5h. In acetonitrile, the amine became a catalyst to form 6-bromo-3-(5-bromo-2-hydroxybenzyl)-2-phenyl-4Hchromen-4-one (5). Under microwave conditions, it took about 20 min to complete the reaction and gave the same yields as theconventional method. Structures of these compounds were firm with NMR, MS spectra.


RSC Advances ◽  
2015 ◽  
Vol 5 (57) ◽  
pp. 46074-46087 ◽  
Author(s):  
Giovanna Bosica ◽  
John Gabarretta

An environmentally benign, one-pot, A3-coupling reaction of various aldehydes, amines and terminal alkynes for the synthesis of propargylamine was catalysed by Amberlyst A-21 supported CuI, under heterogeneous and solvent-free conditions.


1999 ◽  
Vol 1 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Rajender S. Varma

ChemInform ◽  
2004 ◽  
Vol 35 (28) ◽  
Author(s):  
Juergen O. Metzger

2017 ◽  
Vol 15 (27) ◽  
pp. 5805-5810 ◽  
Author(s):  
Yan Liu ◽  
Jia Yuan ◽  
Zi-Fei Wang ◽  
Si-Hao Zeng ◽  
Meng-Yue Gao ◽  
...  

An efficient solvent-free and aqueous protocol for the Buchwald–Hartwig cross-coupling reaction has been developed. Notably, the catalytic system also efficiently catalyzed the reaction under aqueous conditions.


Synlett ◽  
2004 ◽  
Vol 2004 (11) ◽  
pp. 1980-1984 ◽  
Author(s):  
Mohammad Khodaei ◽  
Ahmad Khosropour ◽  
Mehdi Kookhazadeh

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