![]() Nickel-catalyzed cross-couplings involving carbon–oxygen bonds. Solvent effect on palladium-catalyzed cross-coupling reactions and implications on the active catalytic species. Versatile catalysts for the Suzuki cross-coupling of arylboronic acids with aryl and vinyl halides and triflates under mild conditions. Highly selective biaryl cross-coupling reactions between aryl halides and aryl Grignard reagents: a new catalyst combination of N-heterocyclic carbenes and iron, cobalt, and nickel fluorides. Hatakeyama, T., Hashimoto, S., Ishizuka, K. Synthesis of unsymmetrical biaryls by electroreductive cobalt-catalyzed cross-coupling of aryl halides. Gomes, P., Fillon, H., Gosmini, C., Labbé, E. Domino rhodium-catalyzed alkyne arylation/palladium-catalyzed N arylation: a mechanistic investigation. Replacing conventional carbon nucleophiles with electrophiles: nickel-catalyzed reductive alkylation of aryl bromides and chlorides. Control of reactive site in palladium-catalyzed Grignard cross-coupling of arenes containing both bromide and triflate. Pd(0)/Au( i) redox incompatibilities as revealed by Pd-catalyzed homo-coupling of Arylgold( i)-complexes. The catalytic cross-coupling of unactivated arenes. ![]() Aryl-aryl bond formation one century after the discovery of the Ullmann reaction. Hassan, J., Sévignon, M., Gozzi, C., Schulz, E. Cooperative catalysis by Ru and Pd for the direct coupling of a chelating aldehyde with iodoarenes or organostannanes. ![]() Bimetallic catalysis using transition and group 11 metals: an emerging tool for C–C coupling and other reactions. The Sonogashira reaction: a booming methodology in synthetic organic chemistry. A convenient synthesis of acetylenes: catalytic substitutions of acetylenic hydrogen with bromoalkenes, iodoarenes and bromopyridines. The Wacker reaction and related alkene oxidation reactions. Olefinoxydation mit Palladiumchlorid-Katalysatoren. Multimetallic Catalysis in Organic Synthesis (Wiley, 2004) Synergistic catalysis: a powerful synthetic strategy for new reaction development. The medicinal chemist’s toolbox: an analysis of reactions used in the pursuit of drug candidates. The growing impact of catalysis in the pharmaceutical industry. Large-scale applications of transition metal-catalyzed couplings for the synthesis of pharmaceuticals. We anticipate that this reaction will simplify the synthesis of pharmaceuticals, many of which are currently made with pre-formed organometallic reagents 1, 2, 3, and lead to the discovery of new multimetallic reactions. Our results reveal a new method for the synthesis of biaryls, heteroaryls, and dienes, as well as a general mechanism for the selective transfer of ligands between two metal catalysts. Although each catalyst forms less than 5 per cent cross-coupled product in isolation, together they are able to achieve a yield of up to 94 per cent. While (1,3-bis(diphenylphosphino)propane)palladium reacts preferentially with aryl triflates to afford a persistent intermediate, (bipyridine)nickel reacts preferentially with aryl bromides to form a transient, reactive intermediate. Selectivity can be achieved without an excess of either substrate and originates from the orthogonal reactivity of the two catalysts and the relative stability of the two arylmetal intermediates. Our method couples aryl bromides with aryl triflates directly, eliminating the use of arylmetal reagents and avoiding the challenge of differentiating between multiple carbon–hydrogen bonds that is required for direct arylation methods 16, 17. Here, we demonstrate that cooperativity between two group 10 metal catalysts-(bipyridine)nickel and (1,3-bis(diphenylphosphino)propane)palladium-enables a general cross-Ullmann reaction (the cross-coupling of two different aryl electrophiles) 13, 14, 15. Many important reactions rely on multimetallic catalysis 5, 6, 7, 8, 9, 10, such as the Wacker oxidation of olefins 6, 7, 8 and the Sonogashira coupling of alkynes with aryl halides 9, 10, but this approach has largely been limited to the use of metals with distinct reactivities, with only one metal catalyst undergoing oxidative addition 11, 12. In cases where a single metal fails to promote a selective or efficient transformation, the synergistic cooperation 4 of two distinct catalysts-multimetallic catalysis-can be used instead. The advent of transition-metal catalysed strategies for forming new carbon-carbon bonds has revolutionized the field of organic chemistry, enabling the efficient synthesis of ligands, materials, and biologically active molecules 1, 2, 3.
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