Resumen de Multicomponent Heterocyclic Chemistry for Undergraduate Organic Laboratory: Biginelli Reaction with Multiple Unknowns
Multicomponent reactions and heterocyclic chemistry are important concepts of organic synthesis, especially in the pharmaceutical industry. A one-pot, multicomponent Biginelli condensation reaction to synthesize dihydropyrimidine derivatives from multiple unknowns is investigated as a discovery-based experiment in a second semester, second-year undergraduate organic chemistry laboratory course. Three 1,3-dicarbonyl compounds, two aryl aldehydes, and urea are utilized to provide six different unknown dihydropyrimidine derivatives with average yields ranging from 63-79%. Students identify their products using 1H NMR, 13C NMR, DEPT, and IR spectroscopic data. The experiment provides an opportunity to discuss multicomponent reactions, carbonyl condensations with amines, enol chemistry, and interpretation of spectra, while being completed in a 3-h laboratory period.
