Direct coupling of aryl halides and alkyllithium compounds by palladium catalysis — ScienceDaily

Palladium catalysts help synthesize key chemicals for many industries. However, direct reaction of two basic reagents, aryl halides and alkyllithium compounds, remains a challenge. Now, a team of scientists have found that a catalyst containing YPhos-type ligands can mediate this reaction even at room temperature. This discovery may contribute to the development of more sustainable processes in the chemical industry, the authors write in the journal Angewandte Chemie.

Palladium-catalyzed chemical processes are very useful. Palladium catalysts help to couple simple carbon-containing compounds to form more complicated chemical structures. However, they have yet failed to couple two common reagents in chemical synthesis, aryl halides and alkyllithium compounds. Among the aryl halides, aryl chlorides are common synthesis reagents that react variably during palladium-catalyzed reactions to produce side products.

For coupling reactions with aryl halides and alkyllithium compounds, chemists usually take “detours” by adding intermediate synthesis steps. Unfortunately, every extra synthesis step

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Noble metal clusters can enhance performance of catalysts and save resources: Lower-cost production thanks to optimized distribution of atoms – publication in Nature Catalysis –

Billions of noble metal catalysts are used worldwide for the production of chemicals, energy generation, or cleaning the air. However, the resources required for this purpose are expensive and their availability is limited. To optimize the use of resources, catalysts based on single metal atoms have been developed. A research team of Karlsruhe Institute of Technology (KIT) demonstrated that noble metal atoms may assemble to form clusters under certain conditions. These clusters are more reactive than the single atoms and, hence, exhaust gases can be much better removed. The results are reported in Nature Catalysis.

Noble metal catalysts are used for a wide range of reactions. Among others, they are applied in nearly all combustion processes to reduce pollutant emissions. Often, they consist of very small particles of the active component, such as a noble metal, which are applied to a carrier material. These so-called nanoparticles are composed of

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