Aim And Objective: The Biginelli reaction, first reported in 1893, is one great example of the important multicomponent reactions reported from 1893. Under the same conditions, the influence of the common catalysts on the yield of the Biginelli reaction was investigated.
Materials And Method: To a round-bottom flask equipped with a spherical condenser were added 1,3- dicarbonyl compound (1.0 eq), urea (1.45 eq), aromatic aldehyde (1.0 eq), catalyst and methanol. The mixture was heated at reflux for 16 h. After cooling off, the mixture was filtered and washed with cold methanol to give DHPMs. Reaction solution was further purified by recrystallization with petroleum ether and ethyl acetate. Six catalytic systems, different 1,3-dicarbonyl compounds and different substituted aromatic aldehydes with varied substitutions are described for the Biginelli reaction. An analysis was also performed to study the factors that affect the yield of the reaction.
Results: When 1,3-dicarbonyl compound was ethyl acetoacetate, the CuCl/ conc.H2SO4 system gave the highest yield (90.5%). While when acetoacetamide was used, the yields of DHPMs in presence of PTSA/conc. HCl, conc. HCl or FeCl3•6H2O were all over 90%. Nine DHPMs with different substituents were obtained.
Conclusion: The Lewis acid or mixed catalyst had no significant advantage over a single protonic acid as catalyst. Conc. HCl as the catalyst was found to be the most effective condition for the preparation of DHPMs. The aromatic aldehyde with weak electron-withdrawing substituent such as Br resulted in the best yield.
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http://dx.doi.org/10.2174/1570179416666181122100405 | DOI Listing |
RSC Adv
December 2024
Department of Chemistry, National Institute of Technology Karnataka (NITK) Surathkal Mangalore-575025 India
3,4-Dihydropyrimidin-2(1)-ones (DHPMs) and 1,4-dihydropyridines (DHPs), prepared by applying the Biginelli and Hantzsch reaction protocols, respectively, are well-documented nitrogen-containing heterocycles with intriguing pharmacological properties. The aqueous solution of biogenic carboxylic acids renewably produced from biomass catalytic or enzymatic processes can be used as a sustainable catalyst and green reaction media for synthesizing DHPs and DHPMs. This work evaluates the efficacy of various biogenic acids in their aqueous solutions as catalysts for synthesizing DHPs and DHPMs from substituted benzaldehydes.
View Article and Find Full Text PDFBioorg Chem
November 2024
Department of Pharmaceutical Organic Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt.
Heliyon
October 2024
Jai Research Foundation, Valvada, Vapi, Gujarat, 396105, India.
The paper describes the construction of a new series of pyrimidinone-linked thiazole derivatives through bromination of the initial Biginelli reaction product followed by the Hantzsch thiazole synthesis route. Various analytical techniques, including FT-IR, H NMR, C NMR, and LCMS analysis, were employed to confirm the formation of the products. The synthesized compounds were primarily evaluated for their antibacterial activity, with a specific focus on their IC values.
View Article and Find Full Text PDFBioorg Chem
December 2024
Department of Science, Institute for Information Technologies Kragujevac, University of Kragujevac, Kragujevac 34000, Serbia. Electronic address:
The aim of the presented research was to explore anticancer potential of eleven newly synthesized tetrahydropyrimidine derivatives. The compounds were synthesized via Biginelli multicomponent one-pot reaction using different derivatives of vanillin, ethyl 4-chloroacetoacetate and (N-methyl)urea. The cytotoxic effects of the compounds were examined on three human malignant cell lines (HeLa, K562, and MCF7), and normal lung fibroblasts MRC-5.
View Article and Find Full Text PDFFront Chem
September 2024
Advanced Materials Division, Mintek, Randburg, South Africa.
Since Strecker's discovery of multicomponent reactions (MCRs) in 1850, the strategy of applying an MCR approach has been in use for over a century. Due to their ability to quickly develop molecular diversity and structural complexity of interest, MCRs are considered an efficient approach in organic synthesis. Although MCRs such as the Ugi, Passerini, Biginelli, and Hantzsch reactions are widely studied, this review emphasizes the significance of selective MCRs to elegantly produce organic compounds of potential use in medicinal chemistry and industrial and material science applications, as well as the use of the MCR approach to sustainable methods.
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