2,3-Dihydropyrrole-2,3-diones 1 thermally extrude CO, giving imidoylketenes 2, which cyclse efficiently to 4-quinolones 3; however, the analogous nitro(imidoyl)ketene 5 eliminates CO2 and rearranges to the 3-oximino-3H-indole 9, presumably via an imidoylnitrile oxide 7.
2,3-二氢
吡咯-2,3-二酮1在热条件下排出CO,生成亚咪酰酮烯2,后者高效环化形成4-
喹啉酮3;然而,类似的硝基(亚咪酰)酮烯5则排出
CO2,并重排生成3-羟
肟基-
3H-吲哚9,可能是通过亚咪酰腈氧化物7实现的。