(PhTe)<sub>2</sub>-Mediated Intramolecular Radical Cyclization of <i>o</i>-Ethynylaryl Isocyanides Leading to Bistellurated Quinolines upon Visible-Light Irradiation
作者:Takenori Mitamura、Kimiyo Iwata、Akiya Ogawa
DOI:10.1021/ol901267h
日期:2009.8.6
Upon treatment with (PhTe)(2) under visible-light irradiation, o-ethynylaryl isocyanides underwent intramolecular radical cyclization with introduction of telluro groups, affording the corresponding bistellurated quinolines.
Photochemical intramolecular cyclization of o-alkynylaryl isocyanides with organic dichalcogenides leading to 2,4-bischalcogenated quinolines
When a mixture of o-alkynylaryl isocyanides and organic dichalcogenides such as diselenides or ditellurides was irradiated with light of wavelength over 300 or 400 nm, the intramolecular cyclization of the isocyanides took place to afford the corresponding 2,4-bischalcogenated quinolines selectively. The photochemical cyclization of 2-(phenylethynyl)phenyl isocyanide could also proceed in the presence of hydrogen transfer reagents such as tris(trimethylsilyl)silane, tributylgermyl hydride, alkanethiols, and benzeneselenol, providing the corresponding 3-phenylquinoline as the result of 2,4-dihydrogenation.