An eco-friendly and magnetized biopolymer cellulose-based heterogeneous acid catalyst for facile synthesis of functionalized pyrimido[4,5-b]quinolines and indeno fused pyrido[2,3-d]pyrimidines in water

Nano-[Fe3O4@SiO2/N-propyl-1-(thiophen-2-yl)ethanimine][ZnCl2] as a nano magnetite Schiff base complex and heterogeneous catalyst for the synthesis of pyrimido[4,5-b]quinolones

“…In a proposed mechanism which is supported by the literature, [17][18][19][20][21][22][23][24]44 in the rst step, dimedone in enole form was reacted with activated aldehyde by the catalyst to give (I) and then by removing of one molecule of H 2 O, intermediate (II) as an Michael acceptor was prepared. In the next step, by the reaction of 6-amino-1,3-dimethyluracil with (II), which was activated by the catalyst, (III) was obtained.…”

“…1 Multi-component reactions are one of the most successful methods in organic chemistry to increase the structural diversity and molecular complexity using a simple process without the formation of side-products and save energy, time, solvent and chemical materials and reduce the chemical waste. [10][11][12][13][14][15][16] Multi-component reaction of aryl aldehyde, dimedone and 6-amino-1,3dimethyluracil is carried out by various catalysts including nano-[Fe 3 O 4 @-SiO 2 @R-NHMe 2 ][H 2 PO 4 ], 1 SBA-15/PrN(CH 2 PO 3 -H 2 ) 2 , 17 [TSSECM], 18 Fe 3 O 4 @cellulose sulfuric acid, 19 Agarentrapped sulfonated DABCO, 20 [C 4 (DABCO) 2 ]$2OH, 21 nanocrystalline MgO, 22 [H 2 -DABCO][ClO 4 ] 2 (ref. 23) and [bmim]Br.…”

Magnetic Nanoparticles Functionalized with Copper Hydroxyproline Complexes as an Efficient, Recoverable, and Recyclable Nanocatalyst: Synthesis and Its Catalytic Application in a Tandem Knoevenagel–Michael Cyclocondensation Reaction

“…The paramagnetic and insoluble nature of the nanomagnetic allows simple separation of this catalyst from the reaction medium and eliminates the need for catalyst filtration. Although MNPs are nontoxic and could be easily prepared, − low thermal and chemical stability in environmental conditions limits their applications. However, immobilization of these MNPs with a nitrogen-impermeable scabbard is a necessary prerequisite for their potential use in catalyst support and biomedical applications. − Because of their low toxicity, superparamagnetic behavior, and large surface-area-to-volume ratio, MNPs have attracted significant attention in various technological fields. − In recent years, multicomponent reaction (MCR) has emerged in organic synthesis because of the ability to combine three or more starting materials in a flask for the synthesis of a new product. − In fact, one of the most effective procedures for the synthesis of complex structures from simple and available starting materials is MCR, , which has been extensively used in the synthesis of natural product, organic material, and biologically active molecules thanks to some prominent features such as low waste production, high convergence, and high atomic economy. − The main part of a large number of natural products and chemical molecules is 4 H -pyran and its derivatives.…”

Synthesis, characterization, and biological activities of new conjugates of Guanosine grafted on polyvinyl alcohol, carbohydrate chitosan, and cellulose

“…The synthetic strategy for the preparation of starch derivatives bearing aminopyridinium groups (2-aminopyridine, 3-aminopyridine, 4-aminopyridine, 2,3-diaminopyridine, 2,6-diaminopyridine, and 3,4-diaminopyridine) was performed through starch functionalization with chloroacetyl chloride molecule [31]. CL-based magnetic nano-composite functionalized with -SO 3 H groups was synthesized to promote the synthesis of pyrimido [4,5-b] quinolone and pyrido [2,3-d] pyrimidine derivatives [32].…”