Indium-catalyzed Annulation of Indoles with Ethyl (2-Ethynylaryl)methyl Carbonates: Synthesis and Photoluminescent Properties of Aryl- and Heteroaryl[b]carbazoles
Indium-catalyzed Annulation of Indoles with Ethyl (2-Ethynylaryl)methyl Carbonates: Synthesis and Photoluminescent Properties of Aryl- and Heteroaryl[b]carbazoles
Rapid access to benzo-annelated heterocycles, naphthalenes, and polysubstituted benzenes through a novel benzannulation reaction
作者:Inga Cikotiene、Rita Buksnaitiene、Rokas Sazinas
DOI:10.1016/j.tet.2010.11.073
日期:2011.1
mercaptoacetate triggered benzannulation reaction is described. The precursors are heterocyclic, aromatic or acyclic compounds bearing a carbonyl group at ortho position to an internal alkyne. The methodology does not require transition-metal catalysts and moreover it is general for the preparation of wide range of benzo-annelated heterocycles, naphthalenes and benzenes.
Tandem Approach to Benzothieno- and Benzofuropyridines from <i>o</i>-Alkynyl Aldehydes via Silver-Catalyzed 6-<i>endo-dig</i> Ring Closure
作者:Sonu Kumar、Carlos Cruz-Hernández、Shilpi Pal、Rakesh K. Saunthwal、Monika Patel、Rakesh K. Tiwari、Eusebio Juaristi、Akhilesh K. Verma
DOI:10.1021/acs.joc.5b01647
日期:2015.11.6
An operationally simple silver-catalyzed tandem strategy for the synthesis of benzothienopyridines 7a-t and benzofuropyridines 8a-p by the reaction of o-alkynyl aldehyde 4a-t and 5a-p with tert-butylamine 6 under mild reaction conditions is described. The present methodology provides a facile conversion of easily accessible o-alkynyl aldehydes into medicinally useful heterocycles in good to excellent yields under mild and environmentally friendly reaction conditions with excellent regioselectivity. The developed chemistry has been successfully extended for the selective synthesis of C-4 deuterated benzothienopyridines 7u-v and benzofurop-yridines 8q-r. The role of the ethanolic proton in the reaction was validated by deuterium-labeling experiments.