Formation of 1,2-dihydroquinazolin-4(3H)-ones. Reinvestigation of a recently reported 1,3,-4-benzotriazepine synthesis

✍ Scribed by Ferenc Fülöp; Mario Simeonov; Kalevi Pihlaja

• Book ID: 104204559
• Publisher: Elsevier Science
• Year: 1992
• Tongue: French
• Weight: 510 KB
• Volume: 48
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)89014-1

✦ Synopsis

A recent pap@ (Bull. Chem. Sot. Jpn. 59, IS75 /1986/) repotted that the reactions of o-aminobenzylh~ne with benzykieneanilines lead to the fonnatiotl of 1,3,4-benrotriazepitl-5~ne or I-(o-benzylideneaminobetuoyl)-2benz.

yIidenehydrazines, depending on the substituents used. This is shown by the present paper to be incorrect. Depending on the proportions of the reagents, the above reactions lead to I-(o-aminobenzoyl)-2-benzykienehydrazines (7) or 2-a@3-ben~lideneamino-1,2-dihydroquinazolita-4(3H)-ones (8).

The cyclization of o-aminobenzoylhydrazines

1 is a thoroughly studied field of heterocyclic chemistry, since a great variety of potential pharmacon heterocyclest-9 can be produced in this way, depending on the reagents and conditions.

Because of the appreciable number of possible products, certain compounds were initially reported with erroneous structures, which were later corrected.lu-14