New green perspective to dihydropyridines synthesis utilizing modified heteropoly acid catalysts

The Q-Tube-Assisted Green Sustainable Synthesis of Fused Azines: New Synthetic Opportunities via Innovative Green Technology

“…Bearing in mind all of the above and inspired by our previous work utilizing green chemistry tools for the synthesis of biologically active heterocyclic compounds [17][18][19][20] and the recently published work on utilizing the high-pressure Q-tube [21][22][23][24][25], we are boiling point is exceeded during the reaction process. The Arrhenius equation states that reaction rates double when the temperature is raised by 10 °C (Equation (1)).…”

“…Bearing in mind all of the above and inspired by our previous work utilizing green chemistry tools for the synthesis of biologically active heterocyclic compounds [17][18][19][20] and the recently published work on utilizing the high-pressure Q-tube [21][22][23][24][25], we are On the other hand, for a plethora of organic reactions, layered double hydroxides [LDHs] can serve as catalysts [12][13][14][15]. The hydroxyl groups in Mg(OH) 2 [brucite] coordinate octahedrally with some Mg 2+ cations, similar to that in brucite, whereas some Al 3+ ions are substituted with trivalent ions.…”

“…Bearing in mind all of the above and inspired by our previous work utilizing green chemistry tools for the synthesis of biologically active heterocyclic compounds [17][18][19][20] and the recently published work on utilizing the high-pressure Q-tube [21][22][23][24][25], we are encouraged to highlight and confirm the success of the Q-tube system in organic synthesis as economic tools that save energy. In this study, we tested the Q-tube for the reaction of chalcones with nitrogen nucleophils.…”

HPW-Catalyzed environmentally benign approach to imidazo[1,2-a]pyridines

“…In contrast, heteropolyacids (HPAs) have been reported as greener catalysts not only for being a safer alternative to toxic catalysts [ 41 ] but also for providing easy recovery and reuse linked to high selectivity [ 42 ]. An example of HPA is phosphotungstic acid, H 3 PW 12 O 40 (HPW), an inexpensive, non-toxic, and green catalyst with greater chemical and thermal stability in comparison to other heteropolyacids [ 43 ]. HPW has been shown to catalyze MCRs in the synthesis of heterocyclic compounds with high efficiency and chemoselectivity ( Figure 2 ), including functionalized benzo[ c ]chromeno[2,3- a ]phenazine [ 44 ], pyrazolo-fused benzophenazines [ 45 ], 4,5-dioxopyrrolidines [ 46 ], 1,2-dihydropyridine (1,2-DHPs) [ 47 ], pyrimido[4,5- b ]quinoline-tetraones [ 48 ], tetrahydrobenzo[ b ]pyrans and indazolo[2,1- b ]phthalazinetriones [ 49 ].…”

Recent Progresses in the Multicomponent Synthesis of Dihydropyridines by Applying Sustainable Catalysts Under Green Conditions

“…MCRs allow the building of multiple bonds and functionalised scaffolds in a one-pot manner, thus boosting efficiency and minimising the generation of by-products and purification techniques, meeting the green chemistry criteria (Maddila et al, 2020b;Maddila et al, 2020c;Devi et al, 2020). Using green principles has been gaining prominence in sustainable/combinatorial chemistry due to the global urge to enhance green credentials on production (Cioc et al, 2014;Shahid et al, 2017;Mokhtar et al, 2021). Sustainable methodologies by the MCR approach driven by green chemistry and green solvents, replacing the volatile and toxic solvents, are crucial in organic synthesis (Sheldon, 2005;Gu, 2012;Ferrazzano et al, 2019).…”