Iodine-Catalyzed Oxidative Aromatization: A Metal-Free Concise Approach to meta-Substituted Phenols from Cyclohex-2-enones

A metal-free approach to meta-substituted phenols from cyclohex-2-enone via catalytic oxidative aromatization has been developed. The transformations are initiated with a catalytic amount of molecular iodine as the direct oxidant, while dimethyl sulfoxide is employed as the terminal oxidant. This practical approach is capable of avoiding the use of metal promoters and costly reagents, the lengthy synthesis, and overoxidation of products, and thus facilitates the efficient construction of meta-substituted phenol derivatives from inexpensive commercial chemicals under mild conditions. The synthetic utility of this approach is evident in the de novo syntheses of two bioactive molecules with good total yields, in which easily available chemicals were employed, protective groups were not utilized, and no unwanted carbon atoms were removed in each step.