The aryl-aryl coupling reaction of 1-naphthol with SnCl_4 for 2,2'-binaphthol synthesis and its application to the biomimetic synthesis of binaphthoquinone isolated from Plumbago zeylanica

摘要

A simple method for the direct synthesis of 2,2'-binaphthols was developed, utilizing aryl-aryl coupling reaction via electron donor-acceptor complexes of 1-naphthols with SnCl_4. Heating of the complex in a sealed tube afforded the corresponding o-o coupling product in excellent yield. This method was utilized for a biomimetic synthesis of the binaphthoquinone, 3,3'-biplumbagin, isolated from Plumbago zeylanica.