Highly Diastereoselective Synthesis of Orthoquinone Monoketals through λ 3 ‐Iodane‐Mediated Oxidative Dearomatization of Phenols

Versatile chiral substrates for asymmetric synthesis are formed through the spiroketalization of phenols with a chiral substituted ethanol unit O-tethered to the ortho position upon treatment with PhI(OAc)2 (see example; TFE=2,2,2-trifluoroethanol). Intermediates with a six-membered iodine(III)-containing ring (the natural localized molecular orbitals associated with the IC6 bond are shown) undergo ligand coupling to give the spiroketals.