BF<sub>3</sub>·OEt<sub>2</sub>-Promoted Tandem<i>O</i>-Arylation/Hydroxylation: Efficient Synthesis of 2-Hydroxyflavanones from Triazenylaryl-Substituted Diketones
A transition-metal-free tandem O-arylation/hydroxylation approach has been developed for the efficientsynthesis of highly substituted 2-hydroxyflavanonesfromtriazenylaryl-substituteddiketones. The intermediate benzopyrylium cation may be involved in these reactions.