Synthesis and reactions of 11<i>H</i>-benzo[<i>b</i>]pyrano[3,2-<i>f</i>]indolizines an pyrrolo[3,2,1-<i>ij</i>]pyrano[3,2-<i>c</i>]quinolines
作者:Thomas Kappe、Peter Roschger、Birgit Schuiki、Wolfgang Stadlbauer
DOI:10.1002/jhet.5570400215
日期:2003.3
2-Methyl-3H-indoles 1 cyclize with two equivalents of ethyl malonate 2 to form 4-hydroxy-11H-benzo[b]pyrano[3,2-f]indolizin-2,5-diones 3, whereas 2-mefhyl-2,3-dihydro-1H-indoles 9 give under similar conditions regioisomer 8-hydroxy-5-methyl-4,5-dihydro-pyrrolo[3,2,1-ij]pyrano[3,2-c]quinolin-7,10-diones 10. The pyrone rings of 3 and 9 can be cleaved either by alkaline hydrolysis to give 7-acetyl-8-
2-甲基-3 H-吲哚1与两个当量的丙二酸乙酯2环合形成4-羟基-11 H-苯并[ b ]吡喃并[3,2- f ]吲哚并嗪-2,5-二酮3,而2- mefhyl-2,3-dihydro-1 H-吲哚9在相似条件下给出区域异构体8-hydroxy-5-methyl-4,5-dihydro-pyrrolo [3,2,1- ij ] pyrano [3,2- c ]喹啉7,10-二酮10。3和9的吡喃环可通过碱解反应裂解,得到7-乙酰基-8-羟基-10 H-吡啶并[1,2- a ]吲哚-6-酮4或5-乙酰基-6-羟基-2-甲基-1,2-二氢-4 H-吡咯并-[3,2,1- ij ]喹啉-4-酮11。在随后的开环下,用硫酰氯氯化3和9,得到7-二氯乙酰基-8-羟基-10 H-吡啶并[1,2 - a ]吲哚-6-酮5或5-二氯乙酰基-6-羟基-2-甲基- 1,2-二氢-4 H-吡咯并[3,2,1- ij