Abstract
Thermolysis of various 4- and/or 6-methyl-1, 2-diazepines (12a, b and 18a-e), prepared from pyridine and lutidine N-imides (11 and 17a-d) having a methyl group in the 3-position, gave the corresponding 1, 3-diazepines (13 and 19) and the 2-aminopyridine derivatives (14 and 20), whereas 1, 2-diazepines (9a-d) having no methyl group in the 4- or 6-position gave only the parent N-imides (8) and no 1, 3-diazepines. Heating of the 2, 3-diazabicyclo [3. 2. 0] hepta-3, 6-dienes (21a, b) formed from the corresponding 1, 2-diazepines by irradiation also gave the 1, 3-diazepines (13a and 19b).
