N,N-Dialkyl-N'-Chlorosulfonyl Chloroformamidines in Heterocyclic Synthesis. Part XIII. *Cleavage and Rearrangement Reactions of Pyrazolo [1,5-b][1,2,4,6] thiatriazine 1,1-Dioxides

Rebecca Norman, Michael Perkins, Andris Liepa, Craig Francis

    Research output: Contribution to journalArticle

    3 Citations (Scopus)

    Abstract

    Treatment of pyrazolo[1,5-b][1,2,4,6]thiatriazines 1 with the Vilsmeier-Haack reagent afforded pyrazolo[1,5-a][1,3,5]triazines 5. Reaction of compounds 1 with trifluoroacetic anhydride, dimethyl sulfoxide, and triethylamine afforded 5-dimethylsulfanylidene derivatives 8. The guanidino-pyrazole-sulfonic acid 9 was produced from treatment of compounds 1 with trifluoroacetic acid under anhydrous conditions. Similar treatment in the presence of water afforded the desulfonated pyrazolo-guanidine 6. Reactions of 6 with one-carbon electrophiles provided various 4-substituted pyrazolo[1,5-a][1,3,5]triazines 5. Attempted catalytic hydrogenolysis of N7-benzyl pyrazolo[1,5-b][1,2,4,6]thiatriazines 2 in alcohols led to sulfamates 12 from thiatriazine ring cleavage. Ethyl acetate or tert-butanol as solvent allowed successful debenzylation to provide compounds 1. Aminolysis of compounds 2 gave sulfamides 13. Thermal rearrangement of compounds 2 afforded 6-benzyl-pyrazolo[3,4-e][1,2,4]thiadiazines 14.

    Original languageEnglish
    Pages (from-to)61-75
    Number of pages15
    JournalAustralian Journal of Chemistry
    Volume69
    Issue number1
    DOIs
    Publication statusPublished - 2016

    Fingerprint Dive into the research topics of 'N,N-Dialkyl-N'-Chlorosulfonyl Chloroformamidines in Heterocyclic Synthesis. Part XIII. *Cleavage and Rearrangement Reactions of Pyrazolo [1,5-b][1,2,4,6] thiatriazine 1,1-Dioxides'. Together they form a unique fingerprint.

  • Cite this