Ullmann reaction

The Ullmann reaction, also recognized as Ullmann coupling, represents a significant method in organic chemistry for synthesizing biaryl compounds – molecules characterized by two aromatic rings joined by a single carbon-carbon bond. This reaction involves the coupling of two aryl halides, leveraging a copper catalyst to facilitate the bond formation. The reaction, first described by German chemist Fritz Ullmann in 1901, remains a foundational process for creating these vital structural motifs, often used in the synthesis of pharmaceuticals, polymers, and other complex organic molecules.