ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Preparation and ring transformation reactions of 1,2,4-Triazolium-4N-aroylarylazomethylides

H.J. Timpe, V. Schikowski, and K.D. Remmler

Technische Hochschule ,,Carl Schorlemmer" Leuna-Merseburg, Sektion Chemie, DDR-4200 Merseburg

Abstract: 4-Phenacyl-l,2,4-triazolium salts react in the presence of sodium acetate with ^ryldiazonium salts at the methylene group giving 47V-aroylarylazo methylides. With acids a protonation occurs at the exocyclic substituent. In basic media the 47V-ylides give ring-opened products, which react to 1-aryl-3-aroyl-l,2,4-triazoles by a new ring closure including the N⁴ —C⁵ moiety of the initial triazole ring and the total moiety of the exocyclic substituent. At about 80 °C a fragmentation of the exocyclic part proceeds and the formed intermediates dimerize to l,4-dihydro-l,2,4,5-tetrazines.

Full paper in Portable Document Format: 412a259.pdf

Chemical Papers 41 (2) 259–270 (1987)