A DMAP-catalyzed mild and efficient synthesis of 1,2-dihydroquinazolines via a one-pot three-component protocol

International audienceAn efficient and simple method for the synthesis of 1,2-dihydroquinazolines catalyzed by 4-(N,N-dimethylamino) pyridine (DMAP) from readily available aromatic or heteroaromatic aldehydes, 2-aminobenzophenone, and ammonium acetate under mild conditions is described. The scope and limitations of the method are discussed

2-(2-Chloro-8-methylquinolin-3-yl)-4-phenyl-1,2-dihydroquinazoline

In the title compound, C24H18ClN3, the dihydroquinazoline and methyl-substituted quinoline benzene rings make a dihedral angle of 78.18 (4)° and form dihedral angles of 45.91 (5) and 79.80 (4)°, respectively, with the phenyl ring. The dihedral angle between the phenyl ring of dihydroquinazoline and the methyl-substituted benzene ring of quinoline is 78.18 (4)°. The crystal packing can be described as crossed layers parallel to the (011) and (0-11) planes. The structure features N—H...N hydrogen bonds and π–π interactions [centroid–centroid distance between phenyl rings = 3.7301 (9) Å]

2-(4-Chlorophenyl)-4-phenyl-1,2-dihydroquinazoline

In the title compound, C20H15ClN2, the pyrimidine ring is in a flattened half-chair conformation. The phenyl and chloro-substituted benzene rings form dihedral angles of 84.97 (5) and 80.23 (4)°, respectively, with the benzene ring of the dihydroquinazoline group. The dihedral angle between the phenyl and chloro-substituted benzene rings is 61.71 (5)°. In the crystal, molecules are arranged in intersecting layers parallel to (101) and (-102), with N—H...N hydrogen bonds linking molecules along [010]. In addition, a weak C—H...π interaction is observed