Chemoselective Oxidative Spiroetherification and Spiroamination of Arenols Using I/Oxone Catalysis.

We developed a chemoselective oxidative dearomative spiroetherification and spiroamination of arenols using I/oxone catalysis. The intramolecular dearomative C-O and C-N couplings proceeded much more efficiently under slightly acidic conditions to give the corresponding spiro adducts in higher yields compared with previous methods using transition metal or hypervalent iodine catalysts. Control experiments suggested that both hypoiodous acid and iodine might be active species for these reactions.