Highly efficient monophosphine-based catalyst for the palladium-catalyzed suzuki-miyaura reaction of heteroaryl halides and heteroaryl boronic acids and esters

A highly active and efficient catalyst system derived from a palladium precatalyst and monophosphine ligands 1 or 2 for the Suzuki-Miyaura cross-coupling reaction of heteroaryl boronic acids and esters has been developed. This method allows for the preparation of a wide variety of heterobiaryls in good to excellent yields and displays a high level of activity for the coupling of heteroaryl chlorides as well as hindered aryl and heteroaryl halides. Specific factors that govern the efficacy of the transformation for certain heterocyclic motifs were also investigated.     

One step entry to P,O- and P,N-type heterocyclic tertiary phosphine ligands and application in Suzuki-Miyaura cross-coupling reactions

A direct synthesis of conformationally mobile P,O- and P,N-type heterocyclic phosphine ligands is described involving radical-mediated addition of diisobutylphosphine to olefinic-heterocycles. Palladium complexes of the P,N-ligand were determined to be highly active in the Suzuki-Miyaura cross-coupling reactions, including deactivated aryl chlorides.     

Suzuki-Miyaura reactions of arenediazonium salts catalyzed by PD(0)/C. One-pot chemoselective double cross-coupling reactions

The Suzuki-Miyaura cross-coupling of arenediazonium tetrafluoroborate salts with boronic acid partners catalyzed by Pd(0)/C is described as a practical and efficient alternative to classical homogeneous conditions. Reactions conducted in alcoholic solvents proved to be extremely fast using mild conditions. Additionally, we developed a chemoselective double Suzuki-Miyaura cross-coupling in a single reaction vessel allowing the synthesis of unsymmetrical terphenyls.     

Palladium(0)-catalyzed, copper(I)-mediated coupling of boronic acids with cyclic thioamides. selective carbon-carbon bond formation for the functionalization of heterocycles

The palladium-catalyzed cross-coupling of cyclic thioamides with arylboronic acids in the presence of stoichiometric amounts of a copper(I) cofactor is described. The desulfitative carbon-carbon cross-coupling protocol is performed under neutral conditions and can be applied to a range of heterocyclic structures with embedded thioamide fragments. Successful carbon-carbon cross-coupling is independent of the ring size, aromaticity/nonaromaticity, the presence of additional heteroatoms, or other functional groups in the starting thioamide structure. Employing controlled microwave irradiation at 100 degrees C, most cross-couplings can be completed within 2 h and proceed in high yields. An advantage of using thioamides as starting materials is the fact that the system can be tuned to an alternative carbon-sulfur cross-coupling pathway by changing to stoichiometric copper(II) under oxidative conditions. Both types of thioamide cross-couplings are orthogonal to the traditional base-catalyzed Suzuki-Miyaura cross-coupling of aryl halides with boronic acids.     

Suzuki-Miyaura Cross-Coupling of Benzylic Bromides Under Microwave Conditions

A procedure for benzylic Suzuki-Miyaura cross-coupling under microwave conditions has been developed. These conditions allowed for heterocyclic compounds to be coupled. Optimum conditions found were Pd(OAc)₂, JohnPhos as the catalyst and ligand, potassium carbonate as the base, and DMF as the solvent. Using these conditions, a library of structurally diverse compounds was synthesized.     

Suzuki-Miyaura cross-coupling reaction on copper-trans-A(2)B corroles with excellent functional group tolerance

The palladium-catalyzed Suzuki-Miyaura cross-coupling reaction has been investigated on meso-substituted trans-A₂B-corrole using tailored Pd-catalyst systems.We present the first examples of Suzuki-Miyaura cross-coupling reactions on meso-substituted trans-A₂B-corrole derivatives with neutral, sterically hindered, inactivated and heteroaromatic boronic acids and esters, alkenylboronic acids, as well as quickly deboronating aryl boronic acids and benzo-condensated five membered heterocyclic boronic acids. In addition, we established a high-yield procedure for the Suzuki-Miyaura cross-coupling reaction of corroles with neutral boronic acids.Due to the lability of the free-base corrole macrocycles, functionalization of the corrole periphery was performed with the corresponding Cu-metallated species. meso-Substituted trans-A₂B-corrole can hence be regarded as highly versatile platform towards more sophisticated corrole systems.X-ray structure analysis of a functionalized meso-substituted trans-A₂B copper corrole exhibited the typical features of such a Cu-complex: short N-Cu distances and a saddled corrole configuration.Moreover, we observed a sensitivity of the formal oxidation state of the coordinated copper ions towards Suzuki-Miyaura cross-coupling reaction conditions, where the central copper(III) ion approaches the characteristic features of a copper(II) species. This redox behaviour was examined by UV/vis absorption spectra, nuclear magnetic resonance (NMR) experiments and time-dependent density functional theoretical calculations.     

胺作为配体在钯催化偶联反应中应用

对近期我们研究小组及其它研究小组在利用胺作为钯催化偶联反应的配体研究进展进行了总结. 钯/胺作为催化体系主要应用的偶联反应包括: Suzuki-Miyaura交叉反应, Sonogashira交叉反应, Stille交叉反应, Hiyama交叉反应和Heck反应. 研究结果表明胺可以作为价廉和高效的配体促进钯催化交叉偶联反应.     

Solid-phase synthesis of biaryl cyclic peptides by borylation and microwave-assisted intramolecular Suzuki-Miyaura reaction

Miyaura borylation and Suzuki-Miyaura cross-coupling have been combined to set up an efficient strategy for the solid-phase synthesis of biaryl cyclic peptides. The Miyaura borylation was the key step in obtaining the linear peptidyl resin precursor containing both the boronate and the halogenated derivative of an aromatic amino acid. The Suzuki-Miyaura macrocyclization was performed under microwave irradiation leading to biaryl cyclic peptides of different ring sizes.     

Synthesis and Suzuki-Miyaura reactions of 5-halo-3,4-dihydropyrimidin-2(1H)-ones

A novel synthesis of 6-methyl-4-phenyl-5-substituted-3,4-dihydropyrimidin-2(1H)-ones from 6-methyl-4-phenyl-5-halo-3,4-dihydropyrimidin-2(1H)-ones via the Suzuki-Miyaura reaction is reported. These previously unknown heterocyclic halides are easily prepared using the Biginelli multicomponent reaction followed by halodecarboxylation. The effect of varied substitution at the C-4 position on the cross-coupling reaction is also examined.     

The B-Alkyl Suzuki-Miyaura Cross-Coupling Reaction: Development,Mechanistic Study,and Applications in Natural Product Synthesis A list of abbreviations can be found at the end of the article

The development of new reactions that facilitate the creative and efficient synthesis of molecular structures with desirable properties continues to fascinate chemists. The test of a significant contribution is its acceptance over time by the scientific community. The B-alkyl Suzuki-Miyaura cross-coupling reaction appears to be one such reaction. Since its disclosure by Suzuki and Miyaura in 1986, this reaction has been an attractive solution to challenging synthetic problems.     

A simple and highly efficient P,O-type ligand for Suzuki-Miyaura cross-coupling of aryl halides

A simple and efficient hemilabile-type phosphine ligand, found to be highly effective in Suzuki-Miyaura cross-coupling of aryl chlorides with generally low Pd-catalyst loading (0.05%), was prepared in one step based on an economically attractive approach from commercially available benzamide starting material.     

A cycloalkane-based thermomorphic system for palladium-catalyzed cross-coupling reactions

In this paper, we describe a practical and efficient protocol for Sonogashira, Suzuki-Miyaura, and Mizoroki-Heck cross-coupling using a CBT system. The use of substrates with cycloalkane-soluble tags facilitates separation of the desired products and the homogeneous Pd catalyst via simple liquid-liquid extraction, thereby eliminating the need for a catalyst removal process.     

Arylation of Phe and Tyr side chains of unprotected peptides by a Suzuki-Miyaura reaction in water

An efficient arylation in water of tyrosine and phenylalanine side chains from unprotected iodopeptides is accomplished by using Suzuki-Miyaura cross-coupling processes. The method is compatible with the hydrophilic and thermolabile nature of biologically active peptides. Also of interest, the arylated tyrosine peptides can be accessed in one-pot mode starting from native peptides.     

An expedient one-pot synthesis of novel 10-substituted 9-aminophenanthrenes

An efficient synthesis of 9,10-disubstituted phenanthrenes is described in this Letter. These novel useful building blocks were obtained in a one-pot reaction including Suzuki-Miyaura cross-coupling followed by a Dieckmann-Thorpe ring closure under microwave irradiation. The selection of the appropriate reagents and the optimal reaction conditions to isolate the intermediate biphenyl compound or the final substituted phenanthrenes in high yields will be discussed in this Letter.     

Enantioselective synthesis of cis-1,2-disubstituted cyclopentanes and cyclohexanes by Suzuki-Miyaura cross-coupling and iridium-catalyzed asymmetric hydrogenation

A series of 1,2-disubstituted cyclohexene derivatives was prepared through Suzuki-Miyaura cross-coupling of 2-bromo-1-cyclohexenecarbaldehyde or 2-carbomethoxy-1-cyclohexen-1-yl triflate with arylboronates. These tetra-substituted cyclic alkenes were subjected to Ir-catalyzed asymmetric hydrogenation. In this way cis-1-methoxymethyl-2-arylcyclohexanes were obtained in high yield with excellent enantio- and diastereoselectivities (up to >99% ee, >99% cis) by using phosphinomethyloxazolines as ligands. Asymmetric hydrogenation of analogous cyclopentene derivatives, prepared by Suzuki-Miyaura cross-coupling, proved to be more difficult and proceeded with lower enantioselectivities of up to 88% ee. The synthetic potential of this cross-coupling/asymmetric-hydrogenation strategy was demonstrated by an enantioselective route to chiral hexahydrofluorenones.     

One-pot synthesis of new aza- and diaza-aminophenanthrenes

The synthesis of a series of benzo(iso)quinoline and phenanthroline derivatives has been achieved using an efficient one-pot procedure. It proceeds through a Suzuki-Miyaura cross-coupling followed by a Dieckmann-Thorpe ring closure under microwave irradiation and provides easy access to building blocks not readily available through other methods.     

Dabco as an inexpensive and highly efficient ligand for palladium-catalyzed Suzuki-Miyaura cross-coupling reaction

An inexpensive and highly efficient Pd(OAc)(2)/Dabco catalytic system has been developed for the cross-coupling of aryl halides with arylboronic acids. A combination of Pd(OAc)(2) and Dabco (triethylenediamine) was observed to form an excellent catalyst, which affords high TONs (turnover numbers; TONs up to 950 000 for the reaction of PhI and p-chlorophenylboronic acid) for Suzuki-Miyaura cross-coupling of various aryl iodides and bromides with arylboronic acids. [reaction: see text]     

Oxygen-promoted Pd/C-catalyzed Suzuki–Miyaura reaction of potassium aryltrifluoroborates

A simple and highly efficient protocol has been developed for the Pd/C-catalyzed ligand-free Suzuki–Miyaura reaction of potassium aryltrifluoroborates. In this catalytic system, the results demonstrate that oxygen plays a positive role in the cross-coupling reaction. In addition, this catalytic system could be successfully applied to synthesize biaryl compounds containing a carbazole moiety and the catalyst was recycled seven times without significant loss of catalytic activity.     

Total synthesis of kehokorins A and B

The total synthesis of a dibenzofuran rhamnoside, kehokorin A, and its aglycone, kehokorin B, was achieved via a route including Suzuki-Miyaura cross-coupling followed by Ullmann ether synthesis to form a dibenzofuran, stepwise bromination at C7 of the dibenzofuran, a second Suzuki-Miyaura cross-coupling to install a 4-methoxyphenyl group at C7, and rhamnosylation.     

Synthesis of 3-aryl-2-arylamidobenzofurans based on the Curtius rearrangement

The synthesis of novel 3-aryl-2-arylamidobenzofurans has been accomplished via a Curtius rearrangement strategy in four steps from benzofuran-2-carboxylic acids. The requisite Suzuki-Miyaura cross-coupling, with benzyl 3-bromobenzofuran-2-ylcarbamate or 2-arylamido-3-bromobenzofurans, revealed an unusual reductive debromination process due to the presence of the free NH group. This dehalogenation can be suppressed by N-alkylation. DMAP is an efficient reagent for the one-pot conversion of benzyl benzofuran-2-ylcarbamates into the corresponding benzofuran-2-arylamides through aroylation, thus acting both as an acyl transfer reagent and a deprotecting agent of the Cbz group. A mechanism is postulated.