Facile Synthesis of 2-Substituted Quinazolines via Ruthenium(II)-Catalyzed Acceptorless Dehydrogenative Coupling

This study aims to develop a practical and facile one-pot synthesis of 2- substituted quinazolines. Using a commercially available and structurally simple ruthenium( II) complex as the catalyst to synthesize a series of quinazoline derivatives via acceptorless dehydrogenative coupling. The mechanism of this reaction was explored by control reaction and DFT calculation. This protocol offers access to a diverse array of quinazoline derivatives (52 examples) in moderate to excellent yields (29%-98%). In summary, we have developed an efficient one-pot ruthenium (II)-catalyzed ADC synthesis of quinazoline under an air atmosphere. The reaction only produces hydrogen and water as by-products, serving as a sustainable and atom-efficient synthetic approach.