Synthesis of Mesomeric Betaines, [1,2,4]Triazolo[2,3-a]pyridiniumides, via Back-donated 1,6-Cyclization
摘要:
The reaction of [1, 2, 4]triazolium salts (4a, b) with polarized alkenes (1a, b, 2a) in the presence of K2CO3 in CHCl3-EtOH gave the corresponding triazolium N-allylides (5 a-c). Thermolyses of the N-allylides (5 a-c) afforded the 7-imino[1, 2, 4] triazolo[2, 3-a]pyridiniumide derivatives (6a,b) and the 7-oxo-[1,2, 4]triazolo[2, 3-a]pyridiniumide derivative (7a). Similar treatment of the salts (4a, b) with alkenes (1c, 2b) directly yielded mesomeric betaines (7b, c), while the reaction of the salt (4 b) with alkene (2 c) gave the pyrrolo[2, 1-f] [1, 2, 4]triazine derivative (8).
Synthesis of Mesomeric Betaines, [1,2,4]Triazolo[2,3-a]pyridiniumides, via Back-donated 1,6-Cyclization
摘要:
The reaction of [1, 2, 4]triazolium salts (4a, b) with polarized alkenes (1a, b, 2a) in the presence of K2CO3 in CHCl3-EtOH gave the corresponding triazolium N-allylides (5 a-c). Thermolyses of the N-allylides (5 a-c) afforded the 7-imino[1, 2, 4] triazolo[2, 3-a]pyridiniumide derivatives (6a,b) and the 7-oxo-[1,2, 4]triazolo[2, 3-a]pyridiniumide derivative (7a). Similar treatment of the salts (4a, b) with alkenes (1c, 2b) directly yielded mesomeric betaines (7b, c), while the reaction of the salt (4 b) with alkene (2 c) gave the pyrrolo[2, 1-f] [1, 2, 4]triazine derivative (8).