Synthesis of Indolonesvia Radical Cyclization ofN-(2-Halogenoalkanoyl)-Substituted Anilines
作者:Takehiko Nishio、Kyoko Iseki、Norihito Araki、Takenori Miyazaki
DOI:10.1002/hlca.200490294
日期:2005.1
The radical reactions of N-(2-halogenoalkanoyl)-substituted anilines (anilides) of type 1 have been investigated under various conditions. Treatment of compounds 1a–1o with Bu3SnH in the presence of (2,2′-azobis(isobutyronitrile) (AIBN) afforded a mixture of the indolones (oxindoles) 2a–2o and the reduction products 5a–5o (Table 1). In contrast, the N-unsubstituted anilides 1p–1s, 1u, and 1v gave the
已经在各种条件下研究了1型N-(2-卤代链烷酰基)-取代的苯胺(苯胺)的自由基反应。在(2,2'-偶氮二(异丁腈)(AIBN)存在下,用Bu 3 SnH处理化合物1a - 1o,得到吲哚酮(吲哚)2a - 2o和还原产物5a - 5o的混合物(表1)相比之下,N-未取代的苯胺1p - 1s,1u和1v仅给出了相应的还原产物(表1)。用镍粉(表2)或Et 3 B(表3)处理1可获得相似的结果。具有较长N-(苯基烷基)链(例如6和7)的苯胺对自由基环化呈惰性,但N-苄基-2-溴-N,2-二甲基丙酰胺(6b)除外,后者在用镍粉处理后-PrOH,以低收率得到环化产物9b(表4)。在照射时,所述扩展苯胺6,7,10,和11仅产生相应的脱氢溴化产物(表5)。