Thermolysis of some 2,3-diazabicyclo[3.3.0]octene systems

The kinetics and products of thermolysis of 2,3-diazabicyclo[3.3.0]oct-2-ene (1), 2,3-diazabicyclo-[3.3.0]octa-2,7-diene (2), and exo-4-methyl-2,3-diazabicyclo[3.3.0]octa-2,7-diene (3) are described and compared with previously studied pyrazolines. The secondary kinetic isotope effects of 1-d2 and 2-d2 have been measured. The synthesis and nuclear magnetic resonance spectra of these compounds and their thermolysis products are discussed.