1373946-53-2Relevant academic research and scientific papers
Synthesis of some new 1,4-dihydropyridine derivatives through a facile one-pot Hantzsch condensation catalyzed by triethylamine
Ghalem, Wassima,Boulcina, Raouf,Debache, Abdelmadjid
, p. 733 - 737 (2012)
A facile and efficient synthesis of new 1,4-dihydropyridine derivatives was reported via Hantzsch three-component condensation reaction of aldehydes or formylphenylboronic acids, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of triethylamine under solvent-free conditions. The method described here offers several advantages including high yields, short reaction times, and simple work-up procedure.
MIL-101-SO3H metal-organic framework as a Br?nsted acid catalyst in Hantzsch reaction: An efficient and sustainable methodology for one-pot synthesis of 1,4-dihydropyridine
Devarajan, Nainamalai,Suresh, Palaniswamy
, p. 6806 - 6814 (2019/05/10)
A straightforward and efficient methodology for the one-pot multicomponent synthesis of 1,4-dihydropyridine has been developed using MIL-101-SO3H metal-organic framework as a solid Br?nsted acid. The presence of the uniformly distributed Br?nsted acidic sulfonic acid sites throughout the framework and the high stability bestow the catalyst with excellent reactivity towards the synthesis of 1,4-dihydropyridine under simple reaction conditions using renewable ethanol as the solvent. The present methodology tolerates various functional groups and allows the synthesis of 1,4-dihydropyridine derivatives in good to excellent yields through Hantzsch reaction. The developed methodology proceeds under mild conditions, avoids corrosive reagents and special reaction conditions, and is amenable to gram scale synthesis. The sustainable nature of the catalyst was proved by the easy recovery and the reusability of the catalyst, as it was reused several times without loss in activity, which was confirmed from the FTIR, PXRD and SEM analyses of the reused catalyst.
Thioglycerol matrix interactions in the positive ion fast atom bombardment mass spectrometry of several Hantzsch and Biginelli ester derivatives of boronic acids
Martínez, Joel,Abarca, Vida,Pérez, F. Javier,Carranza, Vladimir,Miranda, René
, p. 1573 - 1578 (2013/07/27)
RATIONALE Fast atom bombardment (FAB) ionization is a valuable tool for analyzing non-volatile or thermally labile compounds when harder ionization methods (EI or CI) have been unsuccessful. Unexpected interactions between matrix and analyte may, however, occur in FAB ionization leading to the formation of artifacts whose structures have to be determined. METHODS We used esters synthesized by our research group following green chemistry protocols. Artifacts relating to the target molecules were produced in the solvent cage using positive ion FAB using thioglycerol as the matrix and analyzed by accurate mass measurement. RESULTS Through interactions between thioglycerol and the boron atom, various adducts associated with boron-containing Hantzsch and Biginelli ester derivatives appeared in the FAB mass spectra. These interactions must arise in a solvent cage involving a Lewis acid-base bond. Accurate mass determinations of these adducts confirmed the presence of the target molecules. CONCLUSIONS Interactions between the thioglycerol matrix and the eleven boron-containing Hantzsch and Biginelli ester derivatives in addition to the three reagents were seen in their FAB+ spectra. These interactions, together with their accurate mass determinations, allowed us to determine the structures of the new molecules. Copyright 2013 John Wiley & Sons, Ltd. Copyright
