Taifead r-phoist: Autoxidation of 4-Hydrazinylquinolin-2(1<i>H</i>)-one; Synthesis of Pyridazino[4,3-<i>c</i>:5,6-<i>c</i>′]diquinoline-6,7(5<i>H</i>,8<i>H</i>)-diones