Indole-to-Carbazole Strategy for the Synthesis of Substituted Carbazoles under Metal-Free Conditions
作者:Shanping Chen、Yuxia Li、Penghui Ni、Huawen Huang、Guo-Jun Deng
DOI:10.1021/acs.orglett.6b02762
日期:2016.10.21
An efficient indole-to-carbazole strategy has been developed under metal-free conditions. This carbazole formation was highly promoted by NH4I with high regioselectivity through formal [2 + 2 + 2] annulation of indoles, ketones, and nitroolefins. It thus conveniently enabled the assembly of a large number of diversified carbazole products with good tolerance of a broad range of functional groups.
One-pot synthesis of benzo[c]carbazoles by photochemical annulation of 2-chloroindole-3-carbaldehydes
作者:Cailin Wang、Wei Zhang、Shenci Lu、Jingfei Wu、Zongjun Shi
DOI:10.1039/b808854c
日期:——
A novel and efficient procedure for the synthesis of benzo[c]carbazoles has been achieved in moderate to high yields by the one-potphotochemicalannulations of 2-chloroindole-3-carbaldehydes by styrenes via photodechlorination-initiated coupling of 2-chloroindole-3-carbaldehydes with styrenes, electrocyclic reactions and deformylative aromatization in the presence of pyridine.
One-pot access to tetrahydrobenzo[<i>c</i>]carbazoles from simple ketones by using O<sub>2</sub> as an oxidant
作者:Shuvendu Saha、Modhu Sudan Maji
DOI:10.1039/c9ob02751c
日期:——
diversely functionalized carbazole frameworks starting from protecting group free 2-alkenyl indoles. The employment of easily available unactivated ketones as annulating partners, mostly unexplored for the synthesis of carbazoles, is the major highlight of this protocol. This protocol is step- and atom-economical, uses molecular oxygen as the green oxidant, and gives water as the only by-product and is amenable