FSNews365 The Next Generation of News

Breakthrough in Chemistry: Scientists Unveil Hidden Pathway of the Ullmann Reaction Edited by Fasi Uddin 28 September 2025 The Ullmann reaction, one of the most reliable and time-tested tools in organometallic chemistry, has taken center stage again. For over a century, this copper-mediated process has been trusted for building carbon-carbon and carbon-heteroatom bonds, playing a critical role in drug discovery, material science and industrial chemistry. Now, researchers from the Chinese Academy of Sciences and UCLA have revealed groundbreaking evidence that redefines the copper redox cycle underlying Ullmann reaction. Their work, published in Nature on September 22, uncovers a Cu(I)/Cu(III)/Cu(II)/Cu(III)/Cu(I) pathway — an unexpected yet elegant cycle that could reshape our understanding of copper chemistry. The Ullmann Reaction: A Legacy in Organic Synthesis The Ullmann reaction, first discovered in the early 20th century, is one of the oldest copper-catalyzed coupling reacti...