63574-86-7Relevant academic research and scientific papers
Radical Arylation of Anilines and Pyrroles via Aryldiazotates
Hofmann, Josefa,Gans, Eva,Clark, Timothy,Heinrich, Markus R.
supporting information, p. 9647 - 9656 (2017/07/22)
The radical arylation of anilines and pyrroles can be achieved under transition-metal- and catalyst-free conditions by using aryldiazotates in strongly alkaline aqueous solutions. The aryldiazotates act as protected diazonium ions, which do not undergo azo coupling with electron-rich aromatic substrates, but can still serve as an aryl radical source at slightly elevated temperatures. Based on an improved preparation of aryldiazotates in aqueous solution, homolytic aromatic substitutions of anilines and pyrroles were conducted with good overall yields and high regioselectivity. Moreover, DFT calculations provided further mechanistic insights.
Palladium-catalysed direct desulfitative arylation of pyrroles using benzenesulfonyl chlorides as alternative coupling partners
Jin, Rongwei,Yuan, Kedong,Chatelain, Emmanuelle,Soul, Jean-Franois,Douceta, Henri
, p. 3831 - 3841 (2015/01/16)
The reactivity of pyrrole derivatives for palladium-catalysed desulfitative arylation has been investigated. 1-Methyl-, 1-phenyl- and 1-benzylpyrroles were successfully coupled with a variety of benzenesulfonyl chlorides using a phosphine-free catalyst. Highly regioselective arylations at carbon C2 of pyrroles were observed in all cases. A wide variety of substituents on the benzenesulfonyl derivative was tolerated. It should be noted that even bromo- and iodo-benzenesulfonyl chlorides were successfully coupled with pyrrole derivatives without cleavage of the C-Br or C-I bonds, allowing further transformations. Surprisingly, with indoles, mixtures of C2- and C3-arylation products were obtained.
