This review focuses on various side chain groups based on PDAs published over the last 3 years, covering urea, melamine, ferriferous oxide and coumarin. Perspectives on the remaining challenges and future developments are also proposed.

Ruthenium- and rhodium-catalyzed oxidative couplings between versatile directed aromatic C–H bonds and allylic alcohols have been achieved. This method provides efficient synthesis of functional β-aryl ketones and aldehydes in good to excellent yields, and the carbonyl group in the desired products was a significant synthon for organic synthesis.