The synthesis of 3-substituted 1-methylpyrrolo[1,2-a]pyrazines and 3-substitutedisoquinolines was achieved by the intramolecular cyclisation of 2-acetyl-1-propargylpyrroles and 2-alkynylbenzaldehydes, respectively, in the presence of ammonia under microwave heating. The tandem imination/annulation of 2-alkynylbenzaldehydes was easily accomplished under standard conditions, while TiCl4 was used to
NHC-Mediated Stetter-Aldol and Imino-Stetter-Aldol Domino Cyclization to Naphthalen-1(2<i>H</i>)-ones and Isoquinolines
作者:Debabrata Barman、Tanmoy Ghosh、Krishanu Show、Sudipto Debnath、Tapas Ghosh、Dilip K. Maiti
DOI:10.1021/acs.orglett.1c00337
日期:2021.3.19
N-Heterocyclic carbene-catalyzed tandem Stetter-aldol reaction of phthalaldehyde and α,β-unsaturated ketimines has been developed to afford functionalized naphthalen-1(2H)-one derivatives as the formal [4+2] annulation product. Interestingly, the reaction of aldimines led to the formation of isoquinoline derivatives instead of the expected indanone derivatives as a [4+1] annulation product.
A variety of substituted isoquinoline derivatives can be synthesized in moderate yield by a palladium-catalyzed, microwave-assisted MCR starting from o-bromoarylaldehydes, terminal alkynes, and aqueous ammonia.
Copper-Catalyzed Domino Three-Component Benzannulation: Access to Isoquinolines
作者:Peng Ma、Yuhang Wang、Jianhui Wang
DOI:10.1021/acs.organomet.2c00195
日期:2022.8.22
We report herein the synthesis of isoquinolines through a copper(I)-catalyzed domino reaction. During this transformation, three molecules of terminal alkynes, 2-bromoaryl aldehydes (ketones), and acetamide react together, in a sequence including Sonogashira coupling, condensation, 6-endo-dig cyclization, elimination of acetic acid, and hydrolysis. In this reaction, isoquinolines with broad functional