Dedicated to Professor Kazuo Nagasawa on the occasion of his 60th birthday.
Catechols exhibit unique chemical properties owing to the presence of two hydroxyl
groups on adjacent positions in the benzene ring. Although cross-dehydrogenative coupling
reactions of catechols have a long-standing history, with seminal reports dating back
to the mid-1890s, they have recently garnered renewed attention as strategies for
accessing multisubstituted catechols. Furthermore, achieving catalyst-controlled regioselectivity
in these transformations expands their synthetic utility and enables streamlined access
to structurally diverse catechol derivatives. In this short review, we highlight the
scope and limitations of recently developed strategies for regiodivergent cross-dehydrogenative
coupling reactions of catechols. Emphasis is placed on the mechanistic principles
that govern regioselectivity, thus providing a foundation for the rational design
of future regiodivergent catalytic systems.
Keywords
Regioselectivity - Catechols - Cross-dehydrogenative couplings -
ortho-Quinones - Persistent radicals
