Phosphorus Radical-Initiated Cascade Reaction To Access 2-Phosphoryl-Substituted Quinoxalines
摘要:
An effective radical cascade cyclization strategy was developed, by which a wide range of 2-phosphoryl-substituted quinoxalines were prepared in one pot via reaction of ortho-diisocyanoarenes with diarylphosphine oxides in the presence of AgNO3 under mild reaction conditions.
A halogen-bond-promoted double radical isocyanide insertion with perfluoroalkyliodides is reported. With perfluoroalkyliodides as halogen-bond donors and organic bases as halogen-bond acceptors, fluoroalkyl radicals can be generated by a visible-light-induced single electron transfer (SET) process. The fluoroalkyl radicals are trapped by o-diisocyanoarenes to give quinoxaline derivatives. This mechanistically
A general method for the preparation of o-diisocyanoarenes in moderate to good yields has been developed by the dehydration of o-di(formamido) arenes with trichloromethyl chloroformate at - 78°C to 0°C.
imidazo[1,2-a]pyridine and benzimidazole skeletons through the C–N bond was described as a new type of Buchwald–Hartwig reaction. Furthermore, the bis(imidazo[1,2-a]pyridin-3-yl)aryl-1,2-diamine scaffolds were obtained by changing the equivalent ratio of the starting materials. Some advantages of the protocol are the formation of four new bonds (C═C, C–N), a transition-metal-free reaction, a broad
通过 C-N 键获得多种连接的咪唑并[1,2- a ]吡啶和苯并咪唑骨架的有效程序被描述为一种新型的 Buchwald-Hartwig 反应。此外,通过改变起始材料的当量比获得了双(咪唑并[1,2- a ]吡啶-3-基)芳基-1,2-二胺支架。该方案的一些优点是形成四个新键(C = C,C-N),无过渡金属反应,底物范围广,产率高,反应条件温和。通过DFT计算证实了反应机理。
Visible‐Light‐Induced Radical Cascade Cyclization of o‐Diisocyanoarenes: Synthesis of Diethyl Benzo[a]phenazine‐6,6(5H)‐Dicarboxylate
A visible-light-induced radical cascade cyclization of ortho-diisocyanoarenes for the synthesis of diethyl benzo[a]phenazine-6,6(5H)-dicarboxylates has been developed. This process provides an efficient and convenient protocol for the construction of benzo[a]phenazine skeleton that widely present in biologically active molecules and pharmaceuticals. The reaction takes place under mild conditions and
已开发出用于合成苯并[ a ]吩嗪-6,6(5 H )-二羧酸二乙酯的邻二异氰芳烃的可见光诱导自由基级联环化。该过程为构建广泛存在于生物活性分子和药物中的苯并[ a ]吩嗪骨架提供了一种高效便捷的方案。该反应在温和的条件下进行,以中等至极好的收率获得产物。