Oxalic acid as a versatile catalyst for one pot facile synthesis of 3,4‐dihydropyrimidin‐2‐(1H)‐ones and their thione analogues

Abstract

3,4‐Dihydropyrimidin‐2‐(1H)‐ones and their thione analogues are synthesized from the condensation of aromatic aldehydes, β‐dicarbonyl compound and urea or thiourea in presence of 5 mol% of oxalic acid in ethanol‐water (1:2; v/v) under mild reaction conditions. The yields obtained are better and also the use of very inexpensive catalyst, environmentally benign solvent and easy work‐up are the advantageous aspects of the present method.

One‐potandtwo‐potmethods for chalcone derived pyrimidines synthesis and applications

“…[236] Another bispyrimidine (95) was achieved via two steps cyclization and Schiff base formation to get 65%-89% yield of the product [237] (Scheme 23). Compound (94) showed anticancer and antimicrobial activities with the electronwithdrawing groups (i.e., NO 2 , F, Cl, Br). All dichloro and p-bromo derivatives depicted excellent activities against bacterial, fungal, and cancer infections.…”

“…[85] in acidic or basic media with urea derivatives. [86][87][88][89] Several other strategies have also been reported using either one-pot Flögel reaction, [90] Biginelli reaction, [91][92][93][94][95][96][97] or multipot reactions. [98,99] Besides, various conditions have been employed during the synthesis of pyrimidine (i.e., microwave, [100][101][102] ultrasonic-MW, [103] ultrasonic irradiations.…”

Organocatalysis: Key Trends in Green Synthetic Chemistry, Challenges, Scope towards Heterogenization, and Importance from Research and Industrial Point of View

“…Various organocatalysts such as tartaric acid, oxalic acid, citric acid, and lactic acid were found effective in producing Biginelli products [164][165][166][167][168][169][170][171][172]. Because of the "privileged" green nature of this field, it has become an obligation for scientific community and academic institutions to be mindful and teach this branch of catalysis to students and also keep it as a driving force in the generation and dissemination of knowledge in pursuit of efficient synthetic methodologies and processes using organocatalysts.…”

Water-mediated oxalic acid catalysed one-pot synthesis of 2-(substituted phenyl) phthalazin-1(2H)-ones

“…The development of new and simple synthetic methodologies for various heterocycles from readily available starting materials is an important task in organic synthesis. One-pot reactions using three or four components have gained considerable importance for the rapid and efficient synthesis of a wide variety of organic molecules [1,2]. These reactions have been extensively investigated in organic synthesis primarily due to their ability to generate complex molecules from simple starting materials using a one-step reaction.…”