Palladium catalysts Suzuki-Miyaura coupling

Boronic acid derivatives are easily available and useful substrates especially in the palladium-catalysed Suzuki-Miyaura coupling reaction. In copper-catalysed reactions, they are also versatile starting materials. Dimerisation of arylboronic acids was first reported with copper acetate as a catalyst under ojgrgen at 100 Later, it was found that CuCl(OH)(phen) complex was much more efficient as a catalyst to afford dimer in high yields at 28 °C (Scheme 15.17). ... 

An der Heiden, M. and Plenio, H. (2004) Homogeneous catalysts supported on soluble polymers biphasic Suzuki— Miyaura coupling of aryl chlorides using phase-tagged palladium—phosphine catalysts. Chem. Ear. ]., 10, 1789. 

A rapid and efficient Suzuki-Miyaura coupling protocol utilising fibrous PS-based palladium catalysts (FibreCaF ) and microwave irradiation has been reported by Wang and Sauer (Scheme 8). The biaryl motif 26, formed in this reaction, is an important pharmacophore in many biologically active compounds. Each reaction... 

Polymer-stabilized palladium nanoparticles (or nanoclusters) [125-127] have recently received increasing attention in the field of synthetic organic chemistry [128, 129]. Thus, for example, the poly(iV-vinyl-2-pyrrolidone) (PVP)-supported Pd particle catalyzed the Suzuki-Miyaura coupling in water [130]. Poly(amidoamine) (PAMAM) dendrimer-encapsulated palladium nanoparticles were designed and prepared to provide highly selective catalysts for hydrogenation of olefins [131-133]. Hyperbranched aromatic amides (aramids) and PS-DVB-methacryloylethylenesulfonic acid resin have also been... 

Cross-coupling reactions have also been examined in water using amphiphilic PS-PEG resin-supported palladium complexes. Palladium-catalyzed coupling of aryl halides with aryl(or alkenyl)boronic acids (the so-called Suzuki-Miyaura coupling) took place in aqueous alkaline solution in the presence of polymeric catalyst 59 at 25 °C to give the biaryls in excellent yields [90,... 

Suzuki-Miyaura coupling, involving the reaction of aryl boronic derivatives with aryl halides in the presence of a palladium catalyst, is a very powerful method for the preparation of biaryls. Solutions of aryl bromides or iodides supported on onium salts via an ester link in an RTIL lead to BTSILs that can be engaged in the Suzuki-Miyaura coupling reaction with aryl boronic derivatives. like the Heck reaction, this coupling is also sensitive to the variations in different parameters. The possibility to synthesize libraries of biarylic derivatives by parallel synthesis is illustrated by (Scheme 5.5-39) [51]. 

The Suzuki-Miyaura coupling can also be performed with a ligandless palladium catalyst, using a mixture of water and ammonium salt 93 or pyrrolidinium salt 94 (Scheme 38). These BF4 salts have high melting points (125°C and 160 C, respectively) but melt in water to form a biphasic mixture at much lower temperatures ( 50 C and 80°C). The recycling was not efficient, but salts 93 and 94 can be separated and purified, unUke the case with standard ionic Uquids. 

Secondary phosphine oxides were used as ligands/preligands in palladium catalysts that were useful in the Suzuki-Miyaura coupling, in intramolecular ot-arylations of amides and in the arylation of indoles. ... 

Walker SD, Barder TE, Martinelli JR, Buchwald SL (2004) A Rationally Designed Universal Catalyst for Suzuki-Miyaura Coupling Processes. Angew Chem Int Ed 43 1871 Oh-e T, Miyaura N, Suzuki A (1990) Palladium-catalyzed Cross-coupling Reaction of Aryl or Vinylic Triflates with Organoboron Cmnpounds. Synlett 221... 

The Suzuki-Miyaura coupling joins an alkenyl or aryl borate with an alkenyl or aryl halide in the presence of a palladium catalyst. The stereochemistry of alkenyl reactants is preserved in the coupling. 

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