Copper-Catalyzed Chemodivergent Synthesis of Oxazoles and Imidazolidones by Selective C-O/C-N Cyclization.

Efficient synthesis of phenylalanine-derived oxazoles and imidazolidones can be achieved by copper-catalyzed reactions that are controlled by directing groups and proceed by selective C-O or C-N coupling. This strategy employs inexpensive commercial copper catalysts and readily available starting materials. It uses a convenient reaction procedure and provides a reliable approach to the versatile and flexible assembly of heterocyclic building blocks.