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An efficient protocol for C-O and C-S bonds formation by the cross-coupling reaction of 1,2-di(pyrimidin-2-yl) disulfides with phenols/thiophenols promoted by copper(I) chloride was established. It was discovered that variously substituted di(hetero)aryl disulfides and phenols were well tolerated. This strategy is the conversion of disulfides into hetero-aryl ethers and thioethers by a copper-promoted chemoselective C-S bond cleavage of disulfides. [ABSTRACT FROM AUTHOR]

Pyrimidin-2-yl sulfonate, as an efficient reaction partner, can be easily prepared from cheap commercial materials, reacted with sodium azide and alkynes to give C2-triazolo functionalized pyrimidines in good yields under mild reaction conditions. This procedure eliminates the need to handle organic halides or organic azides, as they are generated in situ, making this already powerful click process even more user-friendly and safe. [ABSTRACT FROM AUTHOR]

New 2-(1,2,3-triazol-1-yl)pyrimidines were synthesized in good yields by the three-component reaction of pyrimidin-2-yl sulfonates, sodium azide and active methylene ketones in the presence of K2CO3 at room temperature. This procedure eliminates the need to handle organic azides in the synthesis of analogous compounds. [ABSTRACT FROM AUTHOR]

Abstract: A Cu (I) generated in situ from Cu(OAc)2·H2O/sodium ascorbate catalyzed one-pot multicomponent reaction for the synthesis of a series of N-functionalized 1,2,3-triazoles with 3,4-dihydropyrimidione from 3,4-dihydropyrimidiones, paraformaldehyde, sodium azide and alkynes is described. Remarkably N-functionalized 1,2,3-triazoles with amide were prepared by this method. This procedure eliminates the need to handle organic halides or organic azides, as they are generated in situ, making this already powerful click process even more user-friendly and safe. [Copyright &y& Elsevier]

New arylahdehyde oxime ethers functionalised with N3-3,4-dihydropyrimidinone and 2,5-quinazolinedione groups were synthesised in moderate to good yields by the reaction of the corresponding 3,4-dihydropyrimidinones and quinazolinediones with paraformaldehyde and arylaldehyde oximes via a one-pot two-step strategy in the presence of chlorotrimethylsilane. The advantages of this method are the simple procedure, the high regioselectivity of the products and the mild reaction conditions. [ABSTRACT FROM AUTHOR]

A series of 2,5,6-trisubstituted imidazo[2,1- b][1,3,4]thiadiazoles via Mannich reaction of imidazo[2,1- b][1,3,4]thiadiazoles with morpholine and formaldehyde were synthesized. Structures of all the newly synthesized compounds are well supported by spectral data such as IR, NMR, Mass, and Elemental analysis. Compound 3a has been confirmed by X-ray diffraction studies. J. Heterocyclic Chem., (2012). [ABSTRACT FROM AUTHOR]

Development of green solvents from renewable resources has gained much attention recently, because of the extensive uses of solvents in almost all of the chemical industry and the predicted disappearance of fossil oil. Here we show that glycerol and PS-PEGOSO3H as a green and recyclable catalyst system were used in the multicomponent reactions for the synthesis of 3,4-dihydropyrimidinones, amidoalkyl naphthols, and dibenzoxanthenes, respectively. Excellent products yields and good recyclability of catalyst and glycerol were achieved. It demonstrates that glycerol is a renewable and recyclable green solvent that is nontoxic, biodegradable, and able to dissolve organic substrates. It was easy to isolate the reaction products by simple extraction. [image omitted] [ABSTRACT FROM AUTHOR]

A simple, inexpensive, and green reaction permitting the synthesis of new C-6 arylsulfonylmethyl 4-aryl-3,4-dihydropyrimidinones in water by S-alkylation of 6-bromomethyl 3,4-dihydropyrimidinones 2 with benzenesulfinic acid anions 3 is reported. The required 6-bromomethyldihydropyrimidone precursors 2 were readily prepared using an organic solid brominating reagent. [ABSTRACT FROM AUTHOR]

Abstract: Polymer bound sulfonic acid was prepared on polystyrene–poly(ethylene glycol) (PS–PEG) resin. The PS–PEG-bound sulfonic acid exhibited good catalytic activity in the Biginelli-type reaction for the synthesis of 3,4-dihydropyrimidinones with good yield and good recyclability (six times). This method presents a remarkable technique toward an efficient synthesis of 3,4-dihydropyrimidinones. [Copyright &y& Elsevier]

The article presents a chemical reactions polysubstituted tetrahydro-4H-pyrido[1,2-a]pyrimidines by using acylation-hydration-michael addition process.

The article presents information on chemical synthesis of arylaldehyde oxime ethers.

This one-pot, two-step protocol gives rise to N-functionalized triazoles by a Cu(I)-catalyzed multicomponent reaction between dihydropyrimidinones, paraformaldehyde, sodium azide, and alkynes. [ABSTRACT FROM AUTHOR]

Iodine-catalyzed three component reaction of quinazoline-2,5-diones, aldehydes, and styrenes provides allylamine derivatives was described. Both paraformaldehyde and ethyl glyoxalate can be applied in this reaction with simple styrenes with high regioselectivity. [ABSTRACT FROM AUTHOR]

Abstract: The Biginelli 3,4-dihydropyrimidin-2(1H)-one was converted to various C2-multifunctionalized pyrimidines via the dehydrogenation and Mitsunobu reaction using amines, alcohols, phenols and carboxylic acids as nucleophiles. A possible mechanism was also proposed to rationalize the formation of products. [Copyright &y& Elsevier]