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On triazoles. XII . The carbamoylation and thiocarbamoylation of 5‐amino‐1,2,4‐triazoles
Author(s) -
Reiter József,
Pongó László,
Dvortsák Péter
Publication year - 1987
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570240637
Subject(s) - chemistry , tautomer , ring (chemistry) , derivative (finance) , stereochemistry , medicinal chemistry , organic chemistry , financial economics , economics
Abstract The reaction of 5‐amino‐3‐R‐1 H ‐1,2,4‐triazoles 1 with isocyanates 2 (X = O) and isothiocyanates 2 (X = S) was studied. It was stated that with isocyanates 3a (X = O) type ring‐carbamoylated products were formed which did not rearrange to the corresponding exo‐carbamoylated derivatives 6a (X = O). On the other hand the thiocarbamoylation of derivatives 1 provided at mild conditions lead to derivatives 3a (X = S) which could be rearranged by heating to derivatives 6a (X = S). In one case the isomeric 4a (X = S) type derivative was also isolated. The comparison of the ir, uv, pmr and cmr spectra of the isomers isolated with the corresponding spectra of the carbamoylated and thiocarbamoylated 3,5‐diamino‐1,2,4‐triazole derivatives helped to prove unequivocally the isomeric and tautomeric structure of compounds obtained giving a possibility to correct many confusions in the literature.