Ligand-free Suzuki-Miyaura Cross-coupling Reaction Research Articles

Water-Soluble Copper(I) Hydroxide Catalyst and Its Formation in Ligand-Free Suzuki–Miyaura Cross-Coupling Reactions

Copper has emerged as an alternative metal for metal-catalyzed cross-coupling reactions due to its low cost, readily availability, and low toxicity. This article reports a water-soluble active molecular catalyst and its formation in the ligand-free Suzuki–Miyaura (SM) cross-coupling reactions with copper iodide as the precatalyst in aqueous solutions. The SM coupling is homogeneous in nature, and the molecular catalyst is Cu(OH) in its singlet electronic state as identified by experimental and computational UV–vis absorption spectroscopy. The Cu(OH) catalyst is generated through the leaching of oval-shaped Cu2O nanoparticles, which are characterized with X-ray Auger electron spectroscopy, X-ray absorption spectroscopy, and transmission electron microscopy. The soluble Cu(OH) species is stable for at least 4 weeks under ambient conditions.

Water-Soluble Palladium Nanoclusters as Catalysts in Ligand-Free Suzuki–Miyaura Cross-Coupling Reactions

Water-Soluble Palladium Nanoclusters as Catalysts in Ligand-Free Suzuki–Miyaura Cross-Coupling Reactions

Synthesis of monodispersed palladium nanoparticle at room temperature and its catalytic activity for Suzuki-Miyaura cross-coupling reaction

A new method has been developed for the synthesis of spherical palladium nanoparticles with narrow size distribution. Pd nanoparticles of average particle size of around 7 nm have been prepared from Pd(OAc) 2 at room temperature in THF using 2-(trimethyl silyl)-ethanol (TMSE) as a reducing as well as capping agent. The catalytic activity of the Pd-nanoparticles has been examined for ligand free Suzuki-Miyaura cross-coupling reaction.

Continuous Ligand-Free Suzuki–Miyaura Cross-Coupling Reactions in a Cartridge Flow Reactor Using a Gel-Supported Catalyst

Continuous Ligand-Free Suzuki–Miyaura Cross-Coupling Reactions in a Cartridge Flow Reactor Using a Gel-Supported Catalyst

Development of Titanium Dioxide-Supported Pd Catalysts for Ligand-Free Suzuki–Miyaura Coupling of Aryl Chlorides

The catalyst activities of various heterogeneous palladium catalysts supported by anatase-, rutile- and brookite-type titanium oxide for ligand-free Suzuki–Miyaura cross-coupling reactions of aryl chlorides were evaluated. Palladium acetate [Pd(OAc)2], supported on anatase-type titanium oxide (TiO2) via acetonitrile solution impregnation process without reduction [Pd/TiO2 (anatase-type)], demonstrated the highest catalyst activity in comparison to those of other titanium oxide (rutile- or brookite-type) supported Pd(OAc)2 without reduction and reduced Pd/TiO2 (anatase-type) [Pd(red)/TiO2 (anatase-type)]. Various aryl chloride and bromide derivatives were smoothly coupled with arylboronic acids including heteroarylboronic acids in the presence of 5–10 mol% Pd/TiO2 (anatase-type) without the addition of any ligands. Although the fresh Pd/TiO2 (anatase-type) catalyst was surprisingly comprised of ca. 1:2 mixture of palladium(II) and palladium(0) species according to X-ray photoelectron spectroscopy (XPS), in spite of no reduction process, significant further increment of palladium(0) species was observed during the Suzuki–Miyaura coupling reaction, and Pd/TiO2 (anatase-type) was converted into a catalyst, which contained palladium(0) species as the main component [ca. 1:5 mixture of palladium(II) and palladium(0) species]. Therefore, the reduction via the electron donation process to the palladium(II) species may have occurred during the reaction on anatase-type titanium oxide.

Microwave-assisted synthesis of new fluorescent indoline-based building blocks by ligand free Suzuki-Miyaura cross-coupling reaction in aqueous media

To obtain novel fluorescent building blocks, an efficient method for the preparation of an arylindoline unit containing heterocyclic derivatives was developed. The method is based on palladium-catalyzed, ligand-free, cross-coupling of 7-bromo- and 5,7-dibromoimidazo[1,2-a]indolone and 8-bromopyrimido[1,2-a]indolone derivatives with (hetero)aryl boronic acids. In the presence of the Pd(OAc)2 catalyst and the Cs2CO3 base, the microwave-assisted cross-coupling reactions of brominated indoline substrates with (hetero)aryl boronic acids proceeded smoothly in aqueous media. The required brominated substrates can be conveniently obtained with excellent yields by treatment of the corresponding fused heterocycles with NBS in acetonitrile. The optical properties of the novel prepared heterocyclic derivatives were studied by UV–vis and fluorescence spectroscopy. The obtained functionalized arylindoline derivatives, exhibit intense fluorescence with significant Stokes shifts and are characterized by high quantum yields.

ChemInform Abstract: Original Access to 5‐Aryluracils from 5‐Iodo‐2′‐deoxyuridine via a Microwave Assisted Suzuki‐Miyaura Cross‐Coupling/Deglycosylation Sequence in Pure Water.

A facile and efficient methodology to obtain various 5-aryluracil derivatives was developed through a two steps sequence: a ligand-free Suzuki-Miyaura cross-coupling reaction starting from totally deprotected 5-iodo-(2′-deoxy)uridine followed by a very simple deglycosylation procedure in pure water with assistance of microwave irradiation.

A novel green protocol for ligand free Suzuki–Miyaura cross-coupling reactions in WEB at room temperature

A highly efficient green protocol for palladium acetate-catalysed ligand-free Suzuki–Miyaura cross-coupling reactions in neat ‘water extract of banana (WEB)’ was developed. Suzuki–Miyaura reaction proceeds in WEB at very short reaction times under ‘ligand/external base/external promoters/organic medium’ free conditions.

Original access to 5-aryluracils from 5-iodo-2′-deoxyuridine via a microwave assisted Suzuki-Miyaura cross-coupling/deglycosylation sequence in pure water

A facile and efficient methodology to obtain various 5-aryluracil derivatives was developed through a two steps sequence: a ligand-free Suzuki-Miyaura cross-coupling reaction starting from totally deprotected 5-iodo-(2′-deoxy)uridine followed by a very simple deglycosylation procedure in pure water with assistance of microwave irradiation.

ChemInform Abstract: Improved Microwave‐Assisted Ligand‐Free Suzuki—Miyaura Cross‐Coupling of 5‐Iodo‐2′‐deoxyuridine in Pure Water.

ChemInformVolume 44, Issue 48 Natural Products ChemInform Abstract: Improved Microwave-Assisted Ligand-Free Suzuki—Miyaura Cross-Coupling of 5-Iodo-2′-deoxyuridine in Pure Water. Shawn Gallagher-Duval, Shawn Gallagher-Duval Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorGwenaelle Herve, Gwenaelle Herve Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorGuillaume Sartori, Guillaume Sartori Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorGerald Enderlin, Gerald Enderlin Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorChristophe Len, Christophe Len Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this author Shawn Gallagher-Duval, Shawn Gallagher-Duval Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorGwenaelle Herve, Gwenaelle Herve Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorGuillaume Sartori, Guillaume Sartori Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorGerald Enderlin, Gerald Enderlin Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this authorChristophe Len, Christophe Len Cent. Rech. Royallieu, ESCOM-UTC, Univ. Technol. Compiegne, F-60200 Compiegne, Fr.Search for more papers by this author First published: 08 November 2013 https://doi.org/10.1002/chin.201348202Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume44, Issue48November 26, 2013 RelatedInformation

Resin-trapped gold nanoparticles: An efficient catalyst for reduction of nitro compounds and Suzuki-Miyaura coupling

Gold in nanoparticle form shows good catalytic activity in contrast to bulk form and is finding applications in a variety of organic reactions. The present investigation describes direct deposition of gold nanoparticles onto commercially available resin by sorption reduction method. Uniformly dispersed nanoparticles of 3–8nm dimensions were characterized by UV–visible spectroscopy, XRD, SEM and TEM, etc. The AuNPs were found to be remarkably stable and active catalysts for the selective reduction of nitro group under mild reaction conditions and microwave-assisted ligand-free Suzuki-Miyaura cross-coupling reaction between aryl halides and phenylboronic acid. Calculated rate constant (2.5×10−2s−1) for the reduction of 4-nitrophenol is among the best reported in the literature. The versatility of both the protocols is demonstrated by taking a number of substrates.

Gel-entrapped bases: A smart window for the ligand-free Suzuki–Miyaura cross-coupling reaction

Abstract A gel-entrapped base has been fabricated by using agarose (biopolymer), and tested in the Suzuki–Miyaura cross-coupling reaction in 95% ethanol. The developed environmentally benign polymer-supported base has low leaching and high stability for the Suzuki–Miyaura cross-coupling reaction to give high yield with green credit.

Modified zeolite immobilized palladium for ligand-free Suzuki–Miyaura cross-coupling reaction

A palladium-based catalyst supported on modified ZSM-5 was successfully prepared by a facile procedure. The prepared heterogeneous catalyst Pd@desilicated ZSM-5 showed an excellent catalytic activity at very low Pd loading (0.02 mol%) for the ligand-free Suzuki–Miyaura coupling reactions of various aryl bromides affording excellent yields of the products. The prepared catalyst presents good recyclability, over four catalytic cycles.

Improved microwave-assisted ligand-free Suzuki–Miyaura cross-coupling of 5-iodo-2′-deoxyuridine in pure water

A facile and efficient methodology for direct synthesis of 5-aryl-2′-deoxyuridines was developed through ligand-free Suzuki–Miyaura cross-coupling reactions starting from totally deprotected 5-iodo-2′-deoxyuridine and various boronic acids. Reactions were performed, in pure water, in the presence of very low loading of palladium either by classical thermal heating or with the assistance of microwave irradiation yielding 5-arylated uridine derivatives in moderate to good yields within short reaction times.

ChemInform Abstract: In situ Generation of Palladium Nanoparticles: Ligand‐Free Palladium Catalyzed Ultrafast Suzuki—Miyaura Cross‐Coupling Reaction in Aqueous Phase at Room Temperature.

Abstract An ultrafast and highly efficient ligand-free Suzuki–Miyaura cross-coupling reaction between aryl bromides/iodides and arylboronic acids using palladium chloride as catalyst in PEG400/H 2 O in air at room temperature has been developed. TEM showed that palladium nanoparticles were generated in situ from PdCl 2 /PEG400/H 2 O without use of other reductants. The catalyst system can be recycled to reuse three times with good yields.

In situ generation of palladium nanoparticles: ligand-free palladium catalyzed ultrafast Suzuki–Miyaura cross-coupling reaction in aqueous phase at room temperature

An ultrafast and highly efficient ligand-free Suzuki–Miyaura cross-coupling reaction between aryl bromides/iodides and arylboronic acids using palladium chloride as catalyst in PEG400/H 2O in air at room temperature has been developed. TEM showed that palladium nanoparticles were generated in situ from PdCl 2/PEG400/H 2O without use of other reductants. The catalyst system can be recycled to reuse three times with good yields.

ChemInform Abstract: Synthesis of C‐6‐Substituted Uridine Phosphonates Through Aerobic Ligand‐Free Suzuki—Miyaura Cross‐Coupling.

An efficient protocol for the construction of C-6-(hetero)aryl-substituted uridine phosphonate analogues utilizing an aerobic, ligand-free Suzuki–Miyaura cross-coupling reaction of a 6-iodo-precursor in aqueous media has been established. The method presents a modular approach toward the target compounds as demonstrated by the synthesis of a small library comprising 14 novel nucleoside phosphonates.

Solid-supported palladium nano and microparticles: an efficient heterogeneous catalyst for ligand-free Suzuki–Miyaura cross coupling reaction

Solid-supported nano and microparticles of Pd(0) (SS-Pd) were prepared and used as heterogeneous catalysts for Suzuki–Miyaura cross coupling reactions of aryl halides (chloro, bromo and iodo) and phenyl boronic acid under mild and ligand-free conditions. Scanning electron microscope (SEM) and UV–vis based studies were performed to observe the distribution of nano and microparticles of palladium over solid surface and their oxidation states. In addition, the catalyst could be reused up to seven runs without significant loss of activity and stable enough under moist conditions.

Synthesis of C-6-substituted uridine phosphonates through aerobic ligand-free Suzuki–Miyaura cross-coupling

An efficient protocol for the construction of C-6-(hetero)aryl-substituted uridine phosphonate analogues utilizing an aerobic, ligand-free Suzuki-Miyaura cross-coupling reaction of a 6-iodo-precursor in aqueous media has been established. The method presents a modular approach toward the target compounds as demonstrated by the synthesis of a small library comprising 14 novel nucleoside phosphonates.