[3+3] CYCLOCONDENSATION OF β-CARBONYL-SUBSTITUTED 1<i>H</i>-BENZO[<i>f</i>]CHROMENES WITH 3-AMINO-1,2,4-TRIAZOLES: SYNTHESIS OF [1,2,4]TRIAZOLO[1,5-<i>a</i>]PYRIMIDINES</i>
DOI:
https://doi.org/10.1007/6981Keywords:
3-amino-1, 2, 4-triazoles, β-carbonyl-substituted 1H-benzo[f]chromenes and 4Н-chromenes, [1, 4]triazolo[1, 5-a]pyrimidines, aza-Michael reaction, cascade reactions, [3 3] cyclocondensationAbstract
The reaction of β-carbonyl-substituted 1H-benzo[f]chromenes with 3-amino-1,2,4-triazoles provides a new avenue for the preparation of [1,2,4]triazolo[1,5-a]pyrimidines containing a (2-hydroxynaphthalen-1-yl)methyl group at position 6. The reaction of 2-trifluoroacetyl-1Н-benzo[f]chromene with 3-amino-5-(methylsulfanyl)-1H-1,2,4-triazole yielded a derivative of a new 4,5,5a,13a-tetrahydro-6H-benzo[5,6]chromeno[3,2-e][1,2,4]triazolo[1,5-a]pyrimidine heterocyclic system. The proposed cascade reaction mechanism includes an aza-Michael reaction, cyclodehydration, and a retro-oxa-Michael reaction.
Authors: Dmitry V. Osipov, Kirill S. Korzhenko1, Vitaly A. Osyanin*, Pavel E. Krasnikov, Yuri N. Klimochkin
