HETEROCYCLIC IONS FROM N-OXIDES OF N-(4-NITROBENZYLIDENE)-2-CYCLOPROPYLANILINE AND N-(4-NITROBENZYLIDENE)-2-CYCLOPROPYLMETHYLANILINE: FORMATION, ISOMERIZATION, AND CONVERSIONS
Keywords:
o-(2-hydroxyalkyl)anilines, heterocyclic ions, N-oxides of N-(4-nitrobenzylidene)-2-cyclopropylanilines, 2,1-benzoxazinium salts, 2,1-benzoxazepinium salts, isomerizationAbstract
The N-oxide of N-(4-nitrobenzylidene)-2-cyclopropylaniline is converted by the action of strong acids into the corresponding 2,1-benzoxazinium derivative. Under identical conditions the N-oxide of N-(4-nitrobenzylidene)-2-cyclopropylmethylaniline forms the corresponding 2,1-benzoxazinium and 2,1-benzoxazepinium salts in a ratio of 1 : 2. The 2,1-benzoxazepinium ions are thermodynamically less stable and are isomerized with time into 2,1-benzoxazinium ions. Treatment of 2,1-benzoxazinium salts with hydrobromic acid solution and subsequent neutralization leads to o-(2-hydroxyalkyl)anilines and p-nitrobenzaldehyde. The effect of the nature of the ortho substituent on the direction of the conversions of the corresponding arylcyclopropanes is discussed.
How to Cite
Trofimova, E. V.; Fedotov, A. N.; Gazzaeva, R. A.; Mochalov, S. S.; Shabarov, Yu. S.; Zefirov, N. S. Chem. Heterocycl. Compd. 2003, 39, 205. [Khim. Geterotsikl. Soedin. 2003, 234.]
For this article in the English edition, see DOI https://doi.org/10.1023/A:1023720525095