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Updated: Jul 17, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
N-N ring opening of diazabicyclo[3.1.0]hexanes with aryl isocyanates and isothiocyanates
Stanislav A Linnik1, Alexander P Molchanov1, Denis V Solovev1
1Institute of Chemistry, Saint Petersburg State University (SPbU), Universitetskaya nab. 7/9, Saint Petersburg 199034, Russian. m.efremova@spbu.ru.
Abstract:
Diazabicyclo[3.1.0]hexanes were shown to react selectively with three equivalents of aryl isocyanate to form 2,4-dioxo-N,1,3-triarylhexahydro-1H-pyrimido[1,2-a][1,3,5]triazine-9(2H)-carboxamides. A reaction with aryl isothiocyanates under similar conditions gives N1,N3-diaryldihydropyrimidine-1,3(2H,4H)-bis(carbothioamides). The addition of boron trifluoride etherate to the diaziridine-isothiocyanate system changes the reaction path giving bridged (N,N'Z,N,N'Z)-N,N'-(3,4,5-trithio-1,7-diazabicyclo[5.3.1]undecane-2,6-diylidene)dianilines.
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