Synthesis of 1,2,4-Triazoles and 1,2,4,6-Tetraazabicyclo[3.3.0]octanes from diphenyl cyanocarbonimidate. Competition between addition of hydrazines to esters or nitriles

Article abstract of DOI:10.1016/S0040-4020(01)80516-0

The reaction of hydrazine with suitably substituted isoureas gives tetraazabicyclo[3.3.0]octanes. The products obtained in this reaction are extremely susceptible to the nature of the substrate and the reaction conditions, but a suitable combination of th