Microwave-assisted Palladium catalysed C-H acylation with aldehydes. Synthesis and diversification of 3-acylthiophenes

2022 ◽  
Author(s):  
Carlos Santiago ◽  
Xabier Jimenez-Aberasturi ◽  
Eztizen Leicea ◽  
Marta G. Lete ◽  
Nuria Sotomayor ◽  
...  
Keyword(s):  
Alkyl Aryl ◽  
Microwave Assisted

The use of MW allows the efficient palladium(II)-catalysed C-3 acylation of thiophenes with aldehydes via C(sp2)-H activation for the synthesis of (cyclo)alkyl/aryl thienyl ketones (43 examples). Compared to standard thermal...

scholarly journals Microwave-assisted Efficient Synthesis of Alliodorin and (±)-Curcuhydroquinone

1999 ◽  
Vol 23 (2) ◽  
pp. 164-165
Author(s):  
Goverdhan L. Kad ◽  
Anupam Khurana ◽  
Vasundhara Singh ◽  
Jasvinder Singh
Keyword(s):  
Grignard Reagents ◽  
Methyl Groups ◽  
Efficient Synthesis ◽  
Alkyl Aryl ◽  
Microwave Assisted ◽  
Aryl Bromides ◽  
Key Steps

Terpenoids 1 and 2 have been synthesized from readily available starting materials using Li2CuCI4-catalysed coupling of Grignard reagents with alkyl/aryl bromides and microwave-assisted oxidation of allylic methyl groups, using SeO2/ButOOH adsorbed over SiO2 as key steps.

scholarly journals Optimization of a microwave-assisted extraction procedure for the determination of selected alkyl, aryl, and halogenated phenols in sewage sludge and biosolids

2016 ◽  
Vol 51 (4) ◽  
pp. 344-356 ◽  
Author(s):  
Hing-Biu Lee ◽  
M. Lewina Svoboda ◽  
Thomas E. Peart ◽  
Shirley Anne Smyth
Keyword(s):  
Sewage Sludge ◽  
Extraction Procedure ◽  
Negative Ion ◽  
Gas Chromatography Mass Spectrometry ◽  
Microwave Assisted Extraction ◽  
Alkyl Aryl ◽  
Microwave Assisted ◽  
Assisted Extraction ◽  
Halogenated Phenols

A microwave-assisted extraction method for the determination of 15 alkyl, aryl, and halogenated phenols in sewage sludge and biosolids samples was developed and optimized. The effects of solvent, temperature, time, moisture content, acid, and number of extractions on the recovery of phenols were evaluated. Results indicated that extraction solvent had the greatest impact on the recovery of all phenols while pH had the largest effect on recovery of hexachlorophene and pentachlorophenol. Wet sludge samples were extracted with acetone-hexane mixture in the presence of glacial acetic acid. The extract was evaporated, acetylated by acetic anhydride and cleaned up by silica gel. For dry sludge samples, an optional procedure for the simultaneous extraction and acetylation of phenols was also proposed. Triclosan (TCS) and the alkyl and aryl phenols in sludge extracts were analyzed by gas chromatography-mass spectrometry (GC-MS) in electron-impact mode while polyhalogenated phenols were analyzed by GC-MS in negative ion chemical ionization mode. Method detection limits were ca. 200 ng/g for nonylphenol, <25 ng/g for TCS and other alkyl and aryl phenols, and <5 ng/g for other halogenated phenols. This method has been applied to the determination of phenolic compounds in over 150 sludge and biosolids samples since 2009.

scholarly journals Microwave-assisted synthesis of 2,8-di(alkyl/aryl)-4,6-dichloro-2H,8H-pyrano[3,2-g] chromene-3,7-dicarbaldehydes and their antimicrobial activity

2019 ◽  
Vol 84 (4) ◽  
pp. 355-364
Author(s):  
Rupireddy Venkataramana ◽  
Venkata Chittireddy ◽  
Dongamanti Ashok ◽  
Kudle Rao
Keyword(s):  
Antimicrobial Activity ◽  
Pathogenic Bacteria ◽  
Aromatic Aldehydes ◽  
Conventional Heating ◽  
Microwave Assisted Synthesis ◽  
Good Activity ◽  
One Pot ◽  
Alkyl Aryl ◽  
Microwave Assisted ◽  
Bacteria And Fungi

A series of 2,8-di(alkyl/aryl)-substituted bischromanone derivatives were synthesized in one pot from 4,6-diacetylresorcinol and aliphatic/aromatic aldehydes in the presence of pyrrolidine/piperidine under conventional heating and microwave irradiation. The 2,8-di(alkyl/aryl)-substituted bischromanones were converted into a new series of 4,6-dichloro-3,7-diformyl-2,8-di(alkyl/aryl)-substituted bischromenes using the Vilsmeier?Haack reagent. The structures of the compounds were established based on elemental analysis, IR, 1H-NMR, 13C- -NMR and LC?MS spectral data. All the synthesized compounds were evaluated for their antimicrobial activity. Some of the compounds showed very good activity compared to standard drugs against all the tested pathogenic bacteria and fungi.

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