Visible light enabled [4+2] annulation reactions for anthracenone-furans from 2,3-dibromonaphthoquinone and phenylbenzofurans†
Abstract
A facile visible light promoted approach to anthracenone-furans from readily available 2,3-dibromonaphthoquinones and phenylbenzofurans via a formal Diels Alder reaction is reported. This reaction involves wavelength-selective agitation of 4CzIPN, energy transfer to quinones, recombination of 1,6-biradicals and elimination to give anthracenone-furans in good to excellent yields in one pot.