Metal-free C–H arylation of imidazoheterocycles with aryl hydrazines
作者:Sourav Jana、Sadhanendu Samanta、Avik K. Bagdi、Valerii Z. Shirinian、Alakananda Hajra
DOI:10.1039/c8ra01474d
日期:——
A simple and efficient metal-freearylation of imidazo[1,2-a]pyridines at the C-3 position with arylhydrazine has been achieved at room temperature under ambient air conditions. Various 2,3-disubstituted imidazopyridines and imidazothiazoles were synthesized with high yields. The present methodology demonstrates the usefulness of commercially available aryl hydrazine as an arylating agent.
在室温和环境空气条件下,已经实现了在 C-3 位的咪唑并[1,2- a ]吡啶与芳基肼的简单有效的无金属芳基化。以高产率合成了各种 2,3-二取代的咪唑并吡啶和咪唑噻唑。本方法证明了可商购的芳基肼作为芳基化剂的有用性。
Straightforward Synthesis of Various 2,3-Diarylimidazo[1,2-<i>a</i>]pyridines in PEG<sub>400</sub>Medium through One-Pot Condensation and C-H Arylation
PEG400 is described herein as a suitable medium for the condensation of various 2-amino pyridines with α-bromo ketones. 2-Arylimidazo[1,2-a]pyridines were synthetized in a short time through microwave irradiation in moderate to excellent yields. After optimization, a convenient one-pot process enabled access to 2,3-diarylimidazo[1,2-a]pyridines by using a reduced amount of palladium catalyst without