Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact: purchase@heterocycles.com

Price: ¥ 4,320 (Yen only)
Period: This Article can be accessed for 7 days.

Paper | Regular issue | Vol 41, No. 2, 1995, pp.329-336
Published online, 1st January, 1970
DOI: 10.3987/COM-94-6950
Thermal Reaction of 1,2,4-Triazolium N-Allylides: Formation of Mesomeric Betaines, 1,2,4-Triazolo[4,3-a]pyridiniumides, via Back-donated 1,6-Cyclization

Yoshiro Matsuda*, Yasushige Chiyomaru, Chieko Motokawa, and Takanobu Nishiyori

*School of Pharmaceutical Sciences, Nagasaki University, 1-14, Bunkyo-machi, Nagasaki 852, Japan

Abstract

The reaction of 1,2,4-triazolium salt (7) with polarized olefins (2, 3a,b) in the presence of K2CO3 in CHCl3-EtOH gave the corresponding triazolium N-allylides (8a-c). Thermolyses of the N-allylides (8a,c) afforded the mesomeric betaine (9a) and the 8-amino-1,4-triazolo[4,3-a]pyridine derivative (10). Similar treatment of the salt (7) with polarized olefins (3c,d, 4a) directly yielded mesomeric betaines (9c-e), while the reaction of the salt (7) with polarized olefin (4b) gave the pyrrolo[1,2-d]-1,2,4-triazine derivative (11). The formation of mesomeric betaines is suggested to proceed via back-donated 1,6-cyclization.