26458-45-7Relevant articles and documents
Copper-promoted oxidative coupling of enamides and alkynes for the synthesis of substituted pyrroles
Zhao, Mi-Na,Ren, Zhi-Hui,Wang, Yao-Yu,Guan, Zheng-Hui
supporting information, p. 1839 - 1842 (2014/03/21)
An efficient copper-promoted oxidative coupling of enamides with alkynes has been developed for the synthesis of substituted pyrroles. The reaction proceeded through C-H and N-H bond functionalization of enamides under mild conditions.
Development of a gold-multifaceted catalysis approach to the synthesis of highly substituted pyrroles: Mechanistic insights via Huisgen cycloaddition studies
Ngwerume, Simbarashe,Lewis, William,Camp, Jason E.
, p. 920 - 934 (2013/04/10)
A novel gold-catalyzed method for the regioselective synthesis of highly substituted pyrroles directly from oximes and alkynes was developed via independent optimization of two key steps of the process. Importantly, a cationic gold(I) species was shown to activate multiple steps along the reaction pathway and therefore act as a multifaceted catalyst. Initial gold-promoted addition of the oxime oxygen to the activated alkyne afforded the O-vinyloxime in situ. The O-vinyloxime was subsequently transformed into the pyrrole via a gold-catalyzed tautomerization, [3,3]-sigmatropic rearrangement, and cyclodehydration process. Notably, this method provides a functional group handle in the form of an ester at the 3/4-position for further exploitation. The proposed mechanistic pathway is supported by a novel application of the Huisgen cycloaddition click reaction, which was used to probe the relative stability of substituted O-vinyloximes. The intermediacy of N-alkenylhydroxylamine O-vinyl ethers and imino ketones or imino aldehydes along the reaction pathway were determined by high-temperature 1H, 2H{1H}, and 13C{1H} NMR experiments. X-ray crystallographic evidence was used to further support the mechanistic hypothesis.
Novel and efficient supramolecular synthesis of pyrroles in the presence of β-cyclodextrin in water
Ramesh,Karnakar,Satish,Nageswar
, p. 1331 - 1334 (2013/02/22)
A simple and efficient synthesis of highly substituted pyrroles was achieved in water medium via multi-component strategy, using amine, DMAD/DEAD as well as phenacyl bromide catalyzed by β-CD. Utilizing this protocol various pyrrole derivatives were synthesized in good to excellent yields.
