Highly efficient conversion of aromatic acylals to 3, 4-dihydropyrimidinones: a new protocol for the Biginelli reaction

Khabazzadeh, Hojatollah; Saidi, Kazem; Sheibani, Hassan

doi:10.3998/ark.5550190.0009.f04

Cited by 15 publications

(5 citation statements)

References 17 publications

(18 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Only 5% reduction in the catalytic activity was found during the consecutive use of recovered catalyst. A novel version of the Biginelli reaction using an acylal 341 as masked carbonyl functionality together with ethyl acetoacetate 225 and urea or thiourea 140/215 to give dihydropyrimidinones 342 has been reported by Khabazzadeh et al 306 The reaction is catalyzed by PWA, PMo or zinc chloride and has been performed in one-pot under solvent-free conditions (Scheme 100). In the optimized conditions, 10 mol%, 20 mol%, and 80 mol% of PWA, PMo, and ZnCl 2 were used, respectively to get the best yields.…”

Section: Containing Two Heteroatomsmentioning

confidence: 99%

Recent developments in solvent-free multicomponent reactions: a perfect synergy for eco-compatible organic synthesis

2012

View full text Add to dashboard Cite

Section: Containing Two Heteroatomsmentioning

confidence: 99%

Recent developments in solvent-free multicomponent reactions: a perfect synergy for eco-compatible organic synthesis

2012

View full text Add to dashboard Cite

“…The first reported example of a modification at the aldehyde building block in the Biginelli reaction was the use of acylals 27 [52]; this masked carbonyl functionality, together with ethyl acetoacetate 3 and urea or thiourea 1 were employed to give dihydropyrimidinones 4 under acid catalysis. The reaction was catalyzed by 12-tungstophosphoric acid (PW), 12-molybdophosphoric acid (PMo) or zinc chloride and performed in a one-pot procedure under solvent-free conditions (Scheme 10).…”

Section: Modification Of the Aldehyde Counterpartmentioning

confidence: 99%

Synthesis of 3,4-Dihydropyrimidin(thio)one Containing Scaffold: Biginelli-like Reactions

et al. 2022

View full text Add to dashboard Cite

The interest in 3,4-dihydropyrimidine-2(1H)-(thio)ones is increasing every day, mainly due to their paramount biological relevance. The Biginelli reaction is the classical approach to reaching these scaffolds, although the product diversity suffers from some limitations. In order to overcome these restrictions, two main approaches have been devised. The first one involves the modification of the conventional components of the Biginelli reaction and the second one refers to the postmodification of the Biginelli products. Both strategies have been extensively revised in this manuscript. Regarding the first one, initially, the modification of one of the components was covered. Although examples of modifications of the three of them were described, by far the modification of the keto ester counterpart was the most popular approach, and a wide variety of different enolizable carbonylic compounds were used; moreover, changes in two or the three components were also described, broadening the substitution of the final dihydropyrimidines. Together with these modifications, the use of Biginelli adducts as a starting point for further modification was also a very useful strategy to decorate the final heterocyclic structure.

show abstract

“…In 2008, Khabazzadeh and co-workers reported, for the first time, the synthesis of Biginelli products using acylals (1,1-diacetates, 30 ) with PW, PMo, or ZnCl 2 as a catalyst under solvent-free conditions (Scheme ). The solventless reaction mixture containing acylals, β-ketoester, urea or thiourea, and the catalyst was heated to afford good yields of DHPMs . Although the protocol was determined to be conventional because of the elevated temperature and moderate yields, but the short reaction time, solvent-free condition, and use of acylals as substrate was a new valuable modification in the Biginelli reaction.…”

Section: Inorganic Polymersmentioning

confidence: 99%

“…The solventless reaction mixture containing acylals, β-ketoester, urea or thiourea, and the catalyst was heated to afford good yields of DHPMs. 145 Although the protocol was determined to be conventional because of the elevated temperature and moderate yields, but the short reaction time, solvent-free condition, and use of acylals as substrate was a new valuable modification in the Biginelli reaction.…”

Section: Acs Combinatorial Sciencementioning

confidence: 99%

Biginelli Reaction: Polymer Supported Catalytic Approaches

et al. 2019

View full text Add to dashboard Cite

The Biginelli product, dihydropyrimidinone (DHPM) core, and its derivatives are of immense biological importance. There are several methods reported as modifications to the original Biginelli reaction. Among them, many involve the use of different catalysts. Also, among the advancements that have been made to the Biginelli reaction, improvements in product yields, less hazardous reaction conditions, and simplified isolation of products from the reaction predominate. Recently, solid-phase synthetic protocols have attracted the research community for improved yields, simplified product purification, recyclability of the solid support, which forms a special economic approach for Biginelli reaction. The present Review highlights the role of polymer-supported catalysts in Biginelli reaction, which may involve organic, inorganic, or hybrid polymers as support for catalysts. A few of the schemes involve magnetically recoverable catalysts where work up provides green approach relative to traditional methods. Some research groups used polymer−catalyst nanocomposites and polymer-supported ionic liquids as catalyst. Solvent-free, an ultrasound or microwave-assisted Biginelli reactions with polymer-supported catalysts are also reported.

show abstract

Highly efficient conversion of aromatic acylals to 3, 4-dihydropyrimidinones: a new protocol for the Biginelli reaction

Cited by 15 publications

References 17 publications

Recent developments in solvent-free multicomponent reactions: a perfect synergy for eco-compatible organic synthesis

Recent developments in solvent-free multicomponent reactions: a perfect synergy for eco-compatible organic synthesis

Synthesis of 3,4-Dihydropyrimidin(thio)one Containing Scaffold: Biginelli-like Reactions

Biginelli Reaction: Polymer Supported Catalytic Approaches

Contact Info

Product

Resources

About