Palladium-catalyzed coupling reactions

About: Palladium-catalyzed coupling reactions is a research topic. Over the lifetime, 223 publications have been published within this topic receiving 17892 citations.

Palladium-catalyzed cross-coupling reactions of organoboron compounds

Abstract: B. Other Catalyti; Process by Transition-Metal Complexes IV. Cross-Coupling Reaction A. Coupling of 1 -Alkenylboron Derivatives: Synthesis of Conjugated Dienes 6. Coupling of Arylboron Derivatives: Synthesis of Biaryls C. Coupling of Alkylboron Derivatives D. Coupling with Triflates E. Synthesis of Vinylic Sulfides F. Coupling with lodoalkanes: Alkyl-Alkyl CouDlino G. Coupling with Other Organic Halides and Boron Reagents V. Head-to-Tail Coupling VI. Carbonylative Coupling VII. Alkoxycarbonylation and Dimerization VIII. Conclusion 2457 2458 2458

Phosphane-Free Palladium-Catalyzed Coupling Reactions: The Decisive Role of Pd Nanoparticles.

Abstract: Nanosized palladium colloids, generated in situ by reduction of PdII to Pd0 [Eq. (a)], are involved in the catalysis of phosphane-free Heck and Suzuki reactions with simple palladium salts such as PdCl2 or Pd(OAc)2, as demonstrated by transmission electron microscopic investigations.

The Development of Versatile Methods for Palladium-Catalyzed Coupling Reactions of Aryl Electrophiles through the Use of P(t-Bu)3 and PCy3 as Ligands

Abstract: Metal-catalyzed coupling reactions of aryl electrophiles with organometallics and with olefins serve as unusually effective tools for forming new carbon−carbon bonds. By 1998, researchers had developed catalysts that achieved reactions of aryl iodides, bromides, and triflates. Nevertheless, many noteworthy challenges remained; among them were couplings of aryl iodides, bromides, and triflates under mild conditions (at room temperature, for example), couplings of hindered reaction partners, and couplings of inexpensive aryl chlorides. This Account highlights some of the progress that has been made in our laboratory over the past decade, largely through the appropriate choice of ligand, in achieving these synthetic objectives. In particular, we have established that palladium in combination with a bulky trialkylphosphine accomplishes a broad spectrum of coupling processes, including Suzuki, Stille, Negishi, and Heck reactions. These methods have been applied in a wide array of settings, such as natural-prod...

From Noble Metal to Nobel Prize: Palladium-Catalyzed Coupling Reactions as Key Methods in Organic Synthesis

Abstract: Palladium is known to a broad audience as a beautiful, but expensive jewellery metal. In addition, it is nowadays found in nearly every car as part of the automotive catalysts, where palladium is used to eliminate harmful emissions produced by internal combustion engines. On the other hand, and not known to the general public, is the essential role of palladium catalysts in contemporary organic chemistry, a topic which has now been recognized with the Nobel Prize for Chemistry 2010. Have a look at any recent issue of a chemical journal devoted to organic synthesis and you will discover the broad utility of palladium-based catalysts. Among these different palladium-catalyzed reactions, the so-called cross-coupling reactions have become very powerful methods for the creation of new C C bonds. In general, bond formation takes place here between less-reactive organic electrophiles, typically aryl halides, and different carbon nucleophiles with the help of palladium. Remember the situation 50 years ago, when palladium began to make its way into organic chemistry. At that time C C bond formation in organic synthesis was typically achieved by stoichiometric reactions of reactive nucleophiles with electrophiles or by pericyclic reactions. Ironically, however, oxidation catalysis was the start of today s carbon–carbon bond-forming methods: The oxidation of olefins to carbonyl compounds, specifically the synthesis of acetaldehyde from ethylene (Wacker process) by applying palladium(II) catalysts, was an important inspiration for further applications. Probably also for Richard Heck, who worked in the 1960s as an industrial chemist with Hercules Corporation. There, in the late 1960s, he developed several coupling reactions of arylmercury compounds in the presence of either stoichiometric or catalytic amounts of palladium(II). Some of this work was published in 1968 in a remarkable series of seven consecutive articles, with Heck as the sole author! Based on the reaction of phenylmercuric acetate and lithium tetrachloropalladate under an atmosphere of ethylene, which afforded styrene in 80% yield and 10% trans-stilbene, he described in 1972 a protocol for the coupling of iodobenzene with styrene, which today is known as the “Heck reaction”. A very similar reaction had already been published by Tsutomo Mizoroki in 1971. However, Mizoroki didn t follow up on the reaction and died too young from cancer. The coupling protocol for aryl halides with olefins can be considered as a milestone for the development and application of organometallic catalysis in organic synthesis and set the stage for numerous further applications. Hence, palladium-catalyzed coupling reactions were disclosed continuously during the 1970s (Scheme 1). One of the related reactions is the Sonogashira coupling of aryl halides with alkynes, typically in the presence of catalytic amounts of palladium and copper salts.