N,N′-Dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent for the synthesis of pyrimidone and pyrimidine derivatives via Biginelli reaction

Green High-Yielding One-Pot Approach to Biginelli Reaction under Catalyst-Free and Solvent-Free Ball Milling Conditions

“…Despite all of the improved methods, organic synthesis methods still have many drawbacks, such as the use of organic solvents, long reaction times, high costs, low yields, nonsustainable catalysts, and purification issues [34][35][36][37][38][39][40].…”

One-pot synthesis of tricyclic dihydropyrimidine derivatives and their biological evaluation

“…11 Among MCRs, Biginelli (aldehydes or ß-keto esters with urea/thiourea) 12 and Traube-Schwarz (α,β-unsaturated carbonyl compounds with amidines, guanidines or heterocyclic amines) 13 reactions are served as powerful tools in the development of 3,4-dihydropyrimidin-2(1H)-ones and tricyclic 1,6-dihydropyrimidines in the presence of promoters such as base, 13a microwave, 13b thiamine hydrochloride, 14 H 3 BO 3 , 15 melamine trisulfonate, 16 ionic liquid (1,1,3,3-N,N,N',N'-tetramethylguanidinium trifluoroacetate or [bmim]BF 4 ), 17-18 N,N'-dichlorobis(2,4,6-trichlorophenyl) urea, 19 α-zirconium sulfophenylphosphonate, 20 H 2 NSO 3 H 21 and tetrabutylammonium hydrogen sulfate (TBAHS). 13d Recently, we have reported the effective and efficient synthesis of pyrimidone derivatives using Biginelli reactions.…”

Recent synthetic methodologies for pyrimidine and its derivatives

“…To overcome these limitations, Rao and colleagues incorporated N, N ′ −dichlorobis (2,4,6-trichlorophenyl)urea 41 in the Biginelli reaction between β -ketoesters 40, arylaldehyde 7, and urea 8 and achieved good to excellent yields of 3,4-dihydropyrimidin-2-(1H) ones 42 (80%-98% yield) (Scheme 9). 25 The N, N ′ −dichlorobis (2,4,6-trichlorophenyl)urea 41 is applied to a variety of reagents due to its high chlorine contents and harmless and stable character. The remarkable property of this reagent is that it releases positive chlorine, which participates in the reaction, while it itself transforms into an insoluble material that can easily be filtered off.…”