An efficient palladium-catalyzed nucleophilic substitution/C–H activation/aromatization cascade reaction between readily available 2-halo-N-Ms-arylamines (Ms = methanesulfonyl) and benzyl halides/sulfonates has been described. A wide variety of phenanthridines were synthesized in a one-pot fashion in moderate to high yields (37–86 %). Notably, this method provides a straightforward, facile approach
Preparation of phenanthridines from N-(o-arylbenzyl)trifluoromethanesulfonamides with 1,3-diiodo-5,5-dimethylhydantoin
作者:Kei Yanai、Hideo Togo
DOI:10.1016/j.tet.2020.131503
日期:2020.10
6-arylphenanthridines and 6-unsubstituted phenanthridines in good to moderate yields, respectively. The reaction proceeds through an oxidative cyclization onto the aromatic ring by sulfonamidyl radicals formed from the N-iodosulfonamides. The present reaction is a one-pot method for the preparation of both 6-arylphenanthridines and 6-unsubstituted phenanthridines from N-(o-arylbenzyl)trifluoromethanesulfonamides
iminyl‐radical formation has been established for the construction of pyridines, quinolines, and phenanthridines from acyl oximes. With fac‐[Ir(ppy)3] as a photoredox catalyst, the acyl oximes were converted by 1 e− reduction into iminyl radical intermediates, which then underwent intramolecular homolytic aromatic substitution (HAS) to give the N‐containing arenes. These reactions proceeded with a broad
已经建立了涉及可见光诱导的亚胺基自由基形成的统一策略,用于从酰基肟中构建吡啶,喹啉和菲啶。用FAC - [的Ir(ppy)3 ]作为催化剂photoredox,酰基肟通过1e中转化-还原成亚氨基自由基中间体,然后行分子内均裂芳族取代(HAS),得到含有N-芳烃其中。这些反应在室温下以宽范围的底物以高收率进行。这种可见光诱导的亚胺基自由基形成策略已成功地应用于五步精简合成苯并[ c ]菲啶生物碱。
Palladium-Catalyzed α-Arylation of Silylenol Ethers in the Synthesis of Isoquinolines and Phenanthridines
A diverse array of isoquinolines and phenanthridines have been accessed by developing a two-step, one-pot method constituting regioselective palladium-catalyzed Kuwajima–Urabe α-arylation of silylenol ethers and acid-mediated deprotection, annulation, and aromatization. Structural diversity in the silylenol ethers leads to three different classes of isoquinolines and phenanthridines from which related