Biginelli Reaction Concepts and Mechanisms

The video tutorial covers multicomponent reactions, focusing on the Biginelli reaction. It explains the reaction's historical background, mechanism, and significance in synthesizing heterocyclic compounds like dihydropyrimidinone. The tutorial also discusses pyrimidine derivatives, their role in nucleic acids, and the potential for enantioselective synthesis using chiral acids. Applications in drug design and modern organic synthesis are highlighted, demonstrating the reaction's enduring relevance.

Which chemist is credited with inventing the Biginelli reaction?

• Giulio Natta

• Alessandro Volta

• Pietro Biginelli

• Amedeo Avogadro

What are the three components involved in the Biginelli reaction?

• Aromatic aldehyde, urea, beta-keto ester

• Aromatic aldehyde, ammonia, beta-keto ester

• Aromatic aldehyde, urea, alpha-keto ester

• Aromatic ketone, urea, beta-keto ester

What is the trivial name for the compound obtained by replacing a carbon atom in benzene with a nitrogen atom?

• Pyridazine

• Pyridine

• Pyrazine

• Pyrimidine

Which pyrimidine derivative is a key component of nucleic acids like DNA and RNA?

• Pyrazine

• Pyridine

• Pyrimidine

• Pyridazine

What is the complete name of the Biginelli reaction product discussed?

• 4-aryl-5-carbethoxy-3,4-dihydropyrimidin-2(1H)-one

• 4-aryl-5-carbethoxy-3,4-dihydropyrazine-2(1H)-one

• 4-aryl-5-carbethoxy-3,4-dihydropyridazine-2(1H)-one

• 4-aryl-5-carbethoxy-3,4-dihydropyridine-2(1H)-one

What is the first step in the proposed mechanism of the Biginelli reaction?

• Formation of a carbamoyl iminium ion

• Formation of an acylimine

• Formation of a hemiaminal

• Formation of an alpha,beta-unsaturated ketoester

Which intermediate is formed after the dehydration step in the Biginelli reaction mechanism?

• Hemiacetal

• Acylimine

• Carbamoyl iminium ion

• Alpha,beta-unsaturated ketoester

What is the role of chiral phosphoric acid in the enantioselective Biginelli reaction?

• It acts as a catalyst

• It acts as a solvent

• It acts as a reactant

• It acts as a nucleophile

Which enantiomer was preferentially obtained in Professor Liu-Zhu Gong's research on the Biginelli reaction?

• Neither enantiomer

• Both enantiomers equally

• R enantiomer

• S enantiomer

What is a common challenge when using aliphatic aldehydes in the Biginelli reaction?

• Lower yields

• Higher yields

• Formation of multiple products

• No reaction occurs