Synthesis and antitubercular activity evaluation of 4-furano-coumarins and 3-furano-chromones
作者:Ankita Singh、Devla Bimal、Rajesh Kumar、Vipin K. Maikhuri、M. Thirumal、Nihar Nalini Senapati、Ashok K. Prasad
DOI:10.1080/00397911.2018.1480041
日期:2018.9.17
Abstract The synthesis of novel 4-furano-coumarins and 3-furano-chromones has been achieved using silver-mediated oxidative C–H/C–H functionalization of 4-ethynylcoumarin/3-ethynylchromone with ethyl acetoacetate in 80%–90% and 82%–90% yields, respectively. The structure of the synthesized compounds was established on the basis of their spectral data analysis and the structure of one of the 4-furano-coumarins
C-Alkynylation of Chromones by Sonogashira Reaction
作者:Tamás Patonay、István Pazurik、Anita Ábrahám
DOI:10.1071/ch13006
日期:——
Sonogashira reaction of bromochromones and -flavones with a bromine atom on their benzene or heterocyclic ring with various terminal alkynes gave the desired products with nearly the same efficiency as the previously used iodine derivatives. The coupling reactions were performed in the presence of [tetrakis(triphenylphosphine)palladium(0)], copper(i) co-catalyst, and triethylamine, resulting in the
An unexpected one step domino conversion of TMS-alkynes to protected ketones in 4-chromenone system
作者:Prabuddha Bhattacharya、Amit Basak
DOI:10.1016/j.tetlet.2013.07.082
日期:2013.9
An unexpected metal-free high yielding one step domino procedure for TMS-deprotection and simultaneous conversion of resulting alkynes to protected carbonyls (ketals) in 4-chromenone systems is reported. A mechanistic rationale involving an allene intermediate is also proposed based on dynamic NMR and mass spectra. (C) 2013 Elsevier Ltd. All rights reserved.
Imidazole-Selective Alkyne Hydroamination under Physiological Conditions
作者:Hyung-Joon Kang、Joon-Ho Lee、Dong-Hyun Kim、Cheon-Gyu Cho
DOI:10.1021/acs.orglett.0c02785
日期:2020.10.2
Imidazole-selective intermolecular hydroamination reaction has been discovered. This unprecedented additive-free addition reaction proceeds in an exclusively regioselective and stereoselective manner with high atom economy under extremely mild reaction conditions.