Naslov
An expedient metal-free cascade route to chromonyl diene scaffolds: thermodynamic vs. kinetic control

Autori
Alizadeh, Abdolali ; Bagherinejad, Akram ; Kayanian, Jasmine ; Vianello, Robert

Izvornik
RSC Advances (2046-2069) 12 (2022), 54; 34946-34950

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
chromonyl diene scaffolds

Sažetak
A piperidine-catalyzed reaction between 3- formylchromone, 1, 3-dimethyl barbituric acid, and ylidenemalononitriles is developed that offers chromonyl diene products in good yields. This cascade reaction proceeds via the insertion of ylidenemalononitriles between the Knoevenagel adduct obtained from 3-formylchromone and 1, 3- dimethylbarbituric acid, where the pyrimidine- based enaminone is integrated with the chromone through the central diene linker. Similarly, introducing pyrimidine-based enaminone into the terminal part of the chromonyl diene scaffold gave an equilibrium mixture of rotational isomers in DMSO, which could be separated and isolated by crystallization. The computational analysis confirmed the role of barbiturate in directing the type of final chromonyl diene via kinetic or thermodynamic control. Moreover, computations revealed that one of these species, observed in the NMR spectra, is produced by the bond cleavage in the spirocyclic intermediate.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA