Fused N-(di)arylamino-pyrrol-2,3-diones I are reacted with diphenylketene,
thiosemicarbazide or 1,2-diaminobenzene to afford the 3-diphenylmethylene p
yrrolones 2, the thiosemicarbazones 4 or the quinoxaline derivatives 5 as w
ell as 6, respectively. Thermolysis of 2b,c,e,f,6b and the pyrrolo-quinoxal
ine 8 afford the corresponding N-deaminated products 3, 7 and 9. Rearrangem
ents into diazapropellanes following a thermally initiated Fischer - indoli
zation as originally expected do not occur.