Thermal rearrangement of 3-acylisoxazole arylhydrazones allowed facile preparation of 2H- 1,2,3-triazoles which were firstly reacted with isoamyl nitrite and then with an opportune arylhydrazine to produce the corresponding a-hydroxyiminohydrazones 8a-h. The reaction of compounds 8a-h with phosphorus pentachloride afforded the desired 4,4'-bitriazoles 1a-h. The a-hydroxyiminoketone derivative 7 or the a-diketone 14 reacted easily with 1,2- phenylenediamine to afford 1,2,3-triazoles 2a-c bearing the quinoxaline moiety at position 4. Improved yields of the quinoxalines 2a-c were obtained when 1,2-phenylenediamine was reacted with the dioxime 15.
Synthesis of new 2,2 '-disubstituted 5,5 '-dimethyl-4,4 '-bitriazoles and 2-(4-triazolyl)quinoxalines
SIMONI, Daniele;RONDANIN, Riccardo
2000
Abstract
Thermal rearrangement of 3-acylisoxazole arylhydrazones allowed facile preparation of 2H- 1,2,3-triazoles which were firstly reacted with isoamyl nitrite and then with an opportune arylhydrazine to produce the corresponding a-hydroxyiminohydrazones 8a-h. The reaction of compounds 8a-h with phosphorus pentachloride afforded the desired 4,4'-bitriazoles 1a-h. The a-hydroxyiminoketone derivative 7 or the a-diketone 14 reacted easily with 1,2- phenylenediamine to afford 1,2,3-triazoles 2a-c bearing the quinoxaline moiety at position 4. Improved yields of the quinoxalines 2a-c were obtained when 1,2-phenylenediamine was reacted with the dioxime 15.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
