One-pot Syntheses of Fused Quinazolines by Reaction of N-(2-Cyanophenyl)chloromethanimidoyl Chloride. I. A New Synthesis of 1,3-Oxazolo- and 1,3-Oxazino[2,3-b]quinazolines

• Main Authors: Pavel Pazdera, Petr Borek, Helena HavliÅ¡ová, Hana DiviÅ¡ová
• Format: Article
• Language: English
• Published: MDPI AG 2000-10-01
• Series: Molecules
• Subjects: N-(2-cyanophenyl)chloromethanimidoyl chloride; 1; 3-oxazolo[2; 3-b]- quinazoline; 3-oxazino[2; 3-b]quinazoline; methanimidoyl chloride; fused quinazolines; one-pot synthesis
• Online Access: http://www.mdpi.com/1420-3049/5/10/1166/
• ISSN: 1420-3049

12H-Benzo[1,3]oxazolo[2,3-b]quinazolin-12-imine (5a), 9-chloro-12Hbenzo[1,3]oxazolo[2,3-b]quinazolin-12-imine (5b), 2,3-dihydro-5H-[1,3]oxazolo[2,3-b]quinazolin-5-imine (5c), 2,3-dihydro-3,3-dimethyl-5H-[1,3]oxazolo[2,3-b]quinazolin-5-imine (5d) and 3,4--dihydro-2H,6H-[1,3]oxazino[2,3-b]quinazolin-6-imine (5e) were synthesized in a one-pot reaction of N-(2-cyanophenyl)chloromethanimidoyl chloride (1) with 2-aminophenols, 2-aminoethanol, and 3-aminopropanol in the presence of a base. The course of the reaction was controlled by the temperature and the amount of base used. N-(2-Cyanophenyl)-(2-hydroxyanilino)methanimidoyl chloride (3a), 2-chloro-3-(2-hydroxyphenyl)-3,4-dihydroquinazolin-4-imine (4a) and 6-imino-2H, 3H, 4H, 6H, 11H-1,3-oxazino[2,3-b]-5-quinazolinium chloride (6) were identified as intermediates of the one-pot process.