Author:
Fong Handrick,Vaughan Keith
Abstract
Diazotization of 2′-aminoacetophenone, followed by coupling with primary aliphatic amines, affords unstable triazenes which readily undergo cyclodehydration over neutral alumina to give 3-alkyl-4-methylene-1,2,3-benzotriazines (5a-d). 3-Aryl-4-methylene-1,2,3-benzotriazines (8a-c) are likewise obtained by cyclodehydration of the stable 1-(ortho-acetylphenyl)-3-aryltriazenes (7a-c). Attempted synthesis of the unsubstituted 4-methylene-1,2,3-benzotriazine (5e), by the same method, did not succeed. 4-Hydroxy-1,2,3-benzotriazines (4) are postulated as intermediates in the cyclodehydration; this hypothesis is supported by the isolation of the stable 4-hydroxy-1,2,3-benzotriazine (12) from the coupling reaction of methylamine with the diazonium salt derived from ortho-aminobenzophenone. An account of a preliminary study of the thermolysis of 3-methyl-4-methylene-1,2,3-benzotriazine (5a) is included.
Publisher
Canadian Science Publishing
Subject
Organic Chemistry,General Chemistry,Catalysis
Cited by
19 articles.
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