1008-88-4Relevant articles and documents
Newly-generated Al(OH)3-supported Pd nanoparticles-catalyzed Stille and Kumada coupling reactions of diazonium salts, (Het)aryl chlorides
Li, Xing,Zhu, Tingting,Shao, Zhongqi,Li, Yingjun,Chang, Honghong,Gao, Wenchao,Zhang, Yongli,Wei, Wenlong
, p. 69 - 75 (2016)
A ligand-free Pd/Al(OH)3 nano-catalyst which is prepared by one-pot three-component method using Pd(PPh3)4, tetra (ethylene glycol), and aluminum tri-sec-butoxide exhibits excellent catalytic activity in Stille cross-couplings of (Het)aryl chlorides, arenediazonium tetrafluoroborate salts with phenyltributylstannane, respectively, and Kumada couplings of (Het)aryl chlorides with various Grignard reagents. More importantly, these two processes show excellent functional group compatibility with moderate to good yields and they are also versatile with respect to not only (Het)aryl chlorides, but also diazonium salts, and heteroaryl Grignard reagents. The nano-catalyst could also be recycled and reused 5 times without loss of activity and decrease of yield.
Pd(OAc)2-catalyzed fluoride-free cross-coupling reactions of arylsiloxanes with aryl bromides in aqueous medium
Shi, Shengyin,Zhang, Yuhong
, p. 5927 - 5930 (2007)
(Chemical Equation Presented) Mild conditions have been developed to achieve the Pd-(OAc)2-catalyzed fluoride-free cross-coupling between the aryl bromides and arylsiloxanes in good to high yields in aqueous medium. The success of the reactions requires the presence of poly(ethylene glycol) (PEG) and 3 equiv of sodium hydroxide. The product was easily separated with ethyl ether extraction, and the catalytic system can be reused eight times with high efficiency.
N-heterocyclic carbene-Pd(II) complex based on theophylline supported on Fe3O4@SiO2 nanoparticles: Highly active, durable and magnetically separable catalyst for green Suzuki-Miyaura and Sonogashira-Hagihara coupling reactions
Esmaeilpour, Mohsen,Sardarian, Ali Reza,Firouzabadi, Habib
, p. 22 - 34 (2018)
In this paper, a novel heterogeneous palladium catalyst was synthesized by anchoring N-heterocyclic carbene-Pd(II) complex based on theophylline on magnetic Fe3O4@SiO2 nanoparticles. The synthesized magnetic composite was characterized by fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray analysis (EDX), thermogravimetric analysis (TGA), vibration sample magnetometry (VSM), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), dynamic light scattering (DLS), N2 adsorption-desorption isotherm analysis (BET), UV–vis spectroscopy and elemental analysis. Also, loading content of palladium on the catalyst was measured by inductive coupled plasma (ICP) analysis. The synthesized catalyst was used successfully for the Suzuki cross-coupling reactions of various aryl halides (I, Br, Cl) with phenylboronic acids. This reaction was best performed in water as a green solvent in the presence of just 0.37–0.5 mol% of the catalyst at 60 °C. Also, we have reported this recyclable catalytic system as a stable phosphine-free Pd catalyst for the Sonogashira cross-coupling of aryl halides (I, Br, Cl) with terminal aromatic and aliphatic alkynes under solvent-free conditions. All coupling reactions proceeded with good to excellent yields. The catalyst showed good stability and was recovered and reused for eight reaction cycles without a significant loss in its catalytic activity. Also, the leaching of the catalyst has been examined by a hot filtration test and ICP-AES analysis.
A pyridine-bridged bis-benzimidazolylidene pincer nickel(ii) complex: Synthesis and practical catalytic application towards Suzuki-Miyaura coupling with less-activated electrophiles
Tu, Tao,Mao, Han,Herbert, Christian,Xu, Mizhi,Doetz, Karl Heinz
, p. 7796 - 7798 (2010)
A novel robust pyridine-bridged bis-benzimidazolylidene nickel pincer complex 3 accessible from inexpensive, commercially available precursors efficiently catalyzes the first practical Suzuki-Miyaura cross-coupling reactions with various less-reactive electrophiles ArX (X = Br, Cl, OTs and OMs) and even tolerates electron-rich, sterically demanding and heterocyclic arenes in the presence of catalytic amounts of PPh3. The Royal Society of Chemistry.
Leaving Group Ability in Nucleophilic Aromatic Amination by Sodium Hydride-Lithium Iodide Composite
Chiba, Shunsuke,Ong, Derek Yiren,Pang, Jia Hao,Takita, Ryo,Watanabe, Kohei
, p. 393 - 398 (2020)
The methoxy group is generally considered as a poor leaving group for nucleophilic substitution reactions. This work verified the superior ability of the methoxy group in nucleophilic amination of arenes mediated by the sodium hydride and lithium iodide through experimental and computational approaches.
Transition-Metal-Free C-H Arylation of Unactivated Arenes with 8-Hydroxyquinoline as a Promoter
Zheng, Xuehua,Wu, Xu-Nian,Chen, Jing-Yi,Luo, Hai-Bin,Wu, Deyan,Wu, Yinuo
, p. 1721 - 1727 (2018)
A method for the transition-metal-free direct C-H arylation of unactivated arenes is developed with aryl bromides as substrates and 8-hydroxyquinoline as an efficient promoter. A variety of biaryl compounds with structural diversity are obtained in moderate to high yields. Mechanistic studies reveal that the reaction proceeds via a homolytic aromatic substitution pathway.
Naphthidine di(radical cation)s-stabilized palladium nanoparticles for efficient catalytic Suzuki-Miyaura cross-coupling reactions
Desmarets, Christophe,Omar-Amrani, Rafik,Walcarius, Alain,Lambert, Jacques,Champagne, Beno?t,Fort, Yves,Schneider, Rapha?l
, p. 372 - 381 (2008)
Stable Pd(0) nanoparticles were prepared at room temperature in 1,4-dioxane from PdCl2 using N,N′-bis(4-methoxyphenyl)-(1,1′-binaphthyl)-4,4′-diamine (naphthidine) as reducing and stabilizing agent. This procedure resulted in Pd(0) particles possessing an average diameter of ca. 25 nm stabilized against aggregation due to a barrier of the naphthidine di(radical cation) Napht2.2+. These particles were evaluated for their capability to act as catalysts in Suzuki-Miyaura coupling reactions. The Pd(0)/Napht2.2+ provides a general and convenient method to prepare biaryls from aryl bromides or iodides and boronic acids with a broad range of functional groups in 1,4-dioxane at 80 °C and under aerobic conditions.
PdEDTA held in an ionic liquid brush as a highly efficient and reusable catalyst for Suzuki reactions in water
Wei, Jun-Fa,Jiao, Jiao,Feng, Jin-Juan,Lv, Jing,Zhang, Xi-Ru,Shi, Xian-Ying,Chen, Zhan-Guo
, p. 6283 - 6286 (2009)
(Chemical Equation Presented) An efficient and reusable catalyst with PdEDTA immobilized in an ionic liquid brush and a green procedure have been developed for coupling aryl iodides and bromides with phenylboronic acid. These reactions were conducted in water under aerobic conditions with water-insoluble or even solid aryl halides. The protocol has the advantages of excellent yields, environmental friendliness, and catalyst recyclability. There was no apparent loss of catalyst efficiency until the 10th cycle.
Palladium-tetraphosphine catalysed cross coupling of aryl bromides with arylboronic acids: Remarkable influence of the nature of the ligand
Feuerstein,Laurenti,Bougeant,Doucet,Santelli
, p. 325 - 326 (2001)
The cis, cis, cis-1,2,3,4-Tetrakis(diphenylphosphinomethyl)cyclopentane- [PdCl(C3H5)]2 system catalyses the cross coupling of aryl bromides with arylboronic acids with very high substrate-catalyst ratios in good yields; a turnover number of 28 000 000 can be obtained for the addition of 4-bromobenzophenone to benzeneboronic acid in the presence of this catalyst.
Ligand-free Suzuki coupling reaction with highly recyclable ionic palladium catalyst, Ti1-xPdxO2-x (x?=?0.03)
Bhat K, Shrikanth,Lanke, Veeranjaneyulu,Prasad, Jagadeesh Dasappa,Prabhu, Kandikere Ramaiah
, (2020)
We synthesized a recyclable palladium ionic catalyst, Ti0.97Pd0.03O1.97, using a solution combustion method (SCM), and characterized by XRD and Rietveld refinement. The synthesized Pd ionic catalyst is stable, insensitive to moisture and air, and easy to handle. The new catalyst has exhibited a phenomenal result for the Suzuki-Miyaura cross-coupling reaction with a broad substrate scope, and the reaction proceeds in an aqueous medium. The new catalyst proved beneficial and produced excellent yields irrespective of aryl halide used in the reaction (electron-rich or electron-poor or heterocyclic compounds) and shown a turnover frequency (TOF) of 14–25 h?1 for different reactions. The catalyst was coated on a cordierite monolith (Mg2Al4Si5O18), which enhanced the applicability of the catalyst, and made the handling and recycling of the catalyst very easy. Suzuki Miyaura reaction was carried out using both Pd-powder catalysts as well as the Pd-coated honeycomb, which gave almost similar results. We have demonstrated the recyclability of Pd coated cordierite monolith and shown the superiority of the catalyst over the other Pd catalysts for the Suzuki-Miyaura reaction.
Dihalogen-bridged NHC-palladium(i) dimers: Synthesis, characterisation and applications in cross-coupling reactions
Pirkl, Nico,Del Grosso, Alessandro,Mallick, Bert,Doppiu, Angelino,Goo?en, Lukas J.
, p. 5275 - 5278 (2019)
A di-iodo-bridged PdI dimer bearing an N-heterocyclic carbene ligand was made accessible via the reduction of [(IPr)PdI2]2 in basic methanol solution. The structural features of [(IPr)PdI]2 were explored by single-crystal X-ray analysis. It was found to be a convenient one-component precatalyst with high activity in Suzuki-Miyaura, Buchwald-Hartwig, and Sonogashira reactions.
Copper-catalyzed Hiyama coupling of (hetero)aryltriethoxysilanes with (hetero)aryl iodides
Gurung, Santosh K.,Thapa, Surendra,Vangala, Adarsh S.,Giri, Ramesh
, p. 5378 - 5381 (2013)
A CuI-catalyzed Hiyama coupling was achieved, which proceeds in the absence of an ancillary ligand for aryl-heteroaryl and heteroaryl-heteroaryl couplings. A P,N-ligand is required to obtain the best product yields for aryl-aryl couplings. In addition to facilitating transmetalation, CsF is also found to function as a stabilizer of the [CuAr] species, potentially generated as an intermediate after transmetalation of aryltriethoxysilanes with Cu I-catalysts in the absence of ancillary ligands.
Solvent-free, palladium-catalyzed Suzuki-Miyaura cross-couplings of aryl chlorides with arylboronic acids
Li, Jin-Heng,Deng, Chen-Liang,Xie, Ye-Xiang
, p. 2433 - 2448 (2007)
Pd(MeCN)2Cl2/PCy3 was found to be an efficient catalytic system for the Suzuki-Miyaura cross-couplings of aryl chlorides with arylboronic acids under solvent-free conditions. Furthermore, the presence of the conventional solvents had deleterious effect on the reaction. In the presence of Pd(MeCN)2Cl2, PCy3, and TBAF (tetra-n-butylammonium fluoride), a number of aryl chlorides including heteroaryl chlorides were coupled with arylboronic acids or heteroarylboronic acids smoothly to afford the corresponding products in moderate to excellent yields. Copyright Taylor & Francis Group, LLC.
Palladium-catalyzed Stille cross-coupling reaction of aryl chlorides using a pre-milled palladium acetate and XPhos catalyst system
Naber, John R.,Buchwald, Stephen L.
, p. 957 - 961 (2008)
A highly active catalyst system based upon a biaryl monophosphine ligand, XPhos, for the palladium-catalyzed Stille reaction has been developed. This method allows for the coupling of aryl chlorides with a range of tributylarylstannanes to produce the corresponding biaryl compounds in good to excellent yields (61-98%) in short reaction times (4 h). Palladium(II) acetate [Pd(OAc)2] and XPhos in a 1:1.1 ratio were milled into a fine powder that was used as pre-catalyst for these reactions.
Visible light-mediated direct arylation of arenes and heteroarenes using diaryliodonium salts in the presence and absence of a photocatalyst
Tobisu, Mamoru,Furukawa, Takayuki,Chatani, Naoto
, p. 1203 - 1205 (2013)
Diaryliodonium salts have been used as aryl radical sources under visible light-mediated photoredox catalysis. Benzene and a range of heteroarenes are arylated with Ar2I+ in the presence of [Ir(ppy)2(bpy)] PF6 upon irradiation with visible light. When pyrroles are used, the arylation proceeds in the absence of a photoredox catalyst. Both processes are initiated by photoinduced single-electron-transfer to Ar2I+, generating aryl radicals.
A general catalyst for Suzuki-Miyaura and Sonogashira reactions of aryl and heteroaryl chlorides in water
Peng, Hui,Chen, Ya-Qin,Mao, Shu-Lan,Pi, Yun-Xiao,Chen, You,Lian, Ze-Yu,Meng, Tong,Liu, Sheng-Hua,Yu, Guang-Ao
, p. 6944 - 6952 (2014)
We report the synthesis of 2-(3-sulfonatomesityl)-5-sulfonatoindenyl) dicyclohexylphosphine hydrate sodium salt and its use in palladium-catalyzed Suzuki-Miyaura and Sonogashira coupling reactions in water (and biphasic water-organic solvent mixtures) to prepare a variety of functionalized biaryls and aryl alkynes in excellent yield. This journal is the Partner Organisations 2014.
Air-Stable Fe3O4@SiO2-EDTA-Ni(0) as an Efficient Recyclable Magnetic Nanocatalyst for Effective Suzuki-Miyaura and Heck Cross-Coupling via Aryl Sulfamates and Carbamates
Dindarloo Inaloo, Iman,Majnooni, Sahar,Eslahi, Hassan,Esmaeilpour, Mohsen
, (2020)
The synthesis of inexpensive and novel air-stable Ni(0) nanoparticles immobilized on the EDTA-modified Fe3O4@SiO2 nanocatalyst was investigated in Suzuki-Miyaura and Heck cross-coupling reactions. This catalytic system displayed a greatly improved substrate scope for the carbon–carbon bond formations starting from a wide range of green and economical electrophiles aryl and heteroaryl carbamates and sulfamates via highly efficient method under mild, operationally simple reaction conditions. The synthesized heterogeneous catalyst was also fully characterized by FT-IR, TEM, XRD, DLS, FE-SEM, UV–Vis, EDX, XPS, TGA, NMR, VSM, ICP and elemental analysis techniques. The heterogeneous magnetic nanocatalyst can easily be recovered by an external magnetic field and reused for the next reactions for at least seven times with negligible leaching of catalyst and no substantial decrement in the activity. All these highlights have made the present protocol an interesting, simple and environmentally benign process with low catalyst loading and easy manipulations.
2-Aminophenyl diphenylphosphinite as an easily accessible ligand for heterogeneous palladium-catalyzed Suzuki-Miyaura reaction in water in the absence of any organic co-solvent
Firouzabadi, Habib,Iranpoor, Nasser,Gholinejad, Mohammad
, p. 2093 - 2097 (2010)
In this article, we have introduced application of 2-aminophenyl diphenylphosphinite as an easily accessible ligand for heterogeneous palladium-catalyzed Suzuki-Miyaura reaction in water in the absence of any organic co-solvent. By using 2-aminophenyl diphenylphosphinite as a ligand and Pd(OAc)2 as the pre-catalyst, structurally different aryl halides (I, Br, Cl) were reacted efficiently with phenylboronic acid in water to produce their corresponding biphenyl products in good to excellent yields under heterogeneous conditions. The catalyst is recyclable and was recycled for seven runs for the reaction of bromobenzene with phenylboronic acid without appreciable loss of its catalytic activity. In this article we have introduced another useful application of 2-aminophenyl diphenylphosphinite as an easily prepared and cheap ligand for heterogeneous palladium-catalyzed Suzuki-Miyaura reaction in water in the absence of any organic co-solvent. By using 2-aminophenyl diphenylphosphinite ligand and Pd(OAc)2 as the pre-catalyst in water, structurally different aryl halides (I, Br, Cl) were efficiently converted to their biphenyl products in good to excellent yields by the reaction with phenyboronic acid under heterogeneous conditions. The heterogeneous catalyst was recyclable and was recycled for several runs for the reaction of bromobenzene with phenylboronic acid.
Synthesis and characterization of R2PN=P(iBuNCH 2CH2)3N: A new bulky electron-rich phosphine for efficient Pd-assisted Suzuki-Miyaura cross-coupling reactions
Kingston, Jesudoss V.,Verkade, John G.
, p. 2816 - 2822 (2007)
(Chemical Equation Presented) Pro-azaphosphatrane 1a [P( 1BuNCH2CH2)3N] reacts with iodine under mild conditions to give [IP-(iBuNCH2CH 2)3N]I in excellent yield, which on subsequent reaction with ammonia followed by deprotonation with KOtBu provided HN=P( iBuNCH2CH2)3N (3a) in quantitative yield. Reaction of 3a with R′2PCl afforded sterically bulky electron-rich phosphines of the type R′2PN=P( iBuNCH2CH2)3N (4) [R′ = Ph (4a), iPr (4b), tBu (4c)]. The Pd(OAc)2/4c catalyst system was particularly efficient for the coupling of arylboronic acids with aryl bromides as well as aryl chlorides to give biaryls in excellent yields.
Efficient coupling of heteroaryl halides with arylboronic acids in the presence of a palladium-tetraphosphine catalyst
Feuerstein, Marie,Doucet, Henri,Santelli, Maurice
, p. 327 - 336 (2003)
Cis, cis, cis-1,2,3,4-tetrakis(diphenylphosphinomethyl) cyclopentane: ·1/2[PdCl(C3H5)]2 system catalyses the Suzuki cross-coupling of heteroaryl halides with a range of arylboronic acids with very high ratio substrate/catalyst in good yields. Substrates such as pyridines, quinolines, thiophenes, an indole, pyrimidines or a furane have been used successfully.
Ligand-Free Bioinspired Suzuki–Miyaura Coupling Reactions using Aryltrifluoroborates as Effective Partners in Deep Eutectic Solvents
Dilauro, Giuseppe,García, Sergio Mata,Tagarelli, Donato,Vitale, Paola,Perna, Filippo M.,Capriati, Vito
, p. 3495 - 3501 (2018)
Pd-catalyzed Suzuki–Miyaura cross-coupling between (hetero)aryl halides (Cl, Br, I) and versatile, moisture-stable mono- and bifunctional potassium aryltrifluoroborates proceeded efficiently and chemoselectively in air and under generally mild conditions; a catalyst loading as low as 1 mol % combined with Na2CO3 as a base in choline chloride/glycerol (1:2) deep eutectic solvent (DES) was used as a sustainable and environmentally responsible medium. The catalyst, base, and DES were easily and successfully recycled up to six times with an E-factor as low as 8.74. Valuable biaryls and terphenyl derivatives were furnished in yields of up to 98 %; over 50 reactions were compared and discussed. The methodology was applied for the synthesis of the nonsteroidal anti-inflammatory drugs Felbinac and Diflunisal.
Combining enabling techniques in organic synthesis: Solid-phase-assisted catalysis under microwave conditions using a stable Pd(II)-precatalyst
Dawood, Kamal M.,Kirschning, Andreas
, p. 12121 - 12130 (2005)
The catalytic activity of a 2-pyridinealdoxime-based Pd(II)-complex covalently anchored via the oxime moiety to a glass/polymer composite material was evaluated in Suzuki-Miyaura cross-coupling reactions of aryl and heteroaryl halides, including arylchlorides, with aryl and heteroaryl boronic acids both under thermal as well as microwave irradiating conditions in water. The stability and reusability of this Pd-precatalyst is part of the present study.
Cross-coupling between 3-pyridylmagnesium chlorides and heteroaromatic halides
Bonnet, Véronique,Mongin, Florence,Trécourt, Fran?ois,Breton, Gilles,Marsais, Francis,Knochel, Paul,Quéguiner, Guy
, p. 1008 - 1010 (2002)
Phenyl- and thienylpyridines were prepared by Pd(0)-catalyzed cross-coupling of 3-pyridylmagnesium chlorides with iodobenzene or iodothiophene at room temperature. Starting from bromo and chloro azines and diazines, the Ni(0)-catalyzed reaction proved more suitable to allow the synthesis of pyridylpyridines, pyridylquinolines and pyridyldiazines.
Pd-catalyzed desulfitative and denitrogenative Suzuki-type reaction of arylsulfonyl hydrazides
Zhong, Shuangling,Sun, Chenggang,Dou, Sen,Liu, Wencong
, p. 27029 - 27033 (2015)
A palladium-catalyzed desulfitative-denitrogenative coupling of arylsulfonyl hydrazides and arylboronic acids with the assistance of catalytic ligands is described. The reaction showed very good selectivity and tolerated a wide range of functionalities without the aid of expensive copper- or silver-based stoichiometric co-oxidants. We have successfully applied this new cross-coupling reaction to the synthesis of terphenyls and OTBN.
Rhodium-catalyzed arylation using arylboron compounds: Efficient coupling with aryl halides and unexpected multiple arylation of benzonitrile
Ueura, Kenji,Satoh, Tetsuya,Miura, Masahiro
, p. 2229 - 2231 (2005)
(Chemical Equation Presented) The Suzuki-Miyaura-type cross-coupling of arylboron compounds with aryl halides proceeds efficiently in the presence of a rhodium-based catalyst system to produce the corresponding biaryls. Furthermore, it has unexpectedly been observed that the treatment with benzonitrile under similar conditions brings about its multiple arylation, in which nucleophilic arylation on the cyano group and subsequent ortho arylation via C-H bond cleavage are involved.
Organocatalytic synthesis of (Het)biaryl scaffoldsviaphotoinduced intra/intermolecular C(sp2)-H arylation by 2-pyridone derivatives
Das, Tapas Kumar,Kundu, Mrinalkanti,Mondal, Biswajit,Ghosh, Prasanjit,Das, Sajal
, p. 208 - 218 (2021/12/29)
A uniqueN,O-bidentate ligand 6-oxo-1,6-dihydro-pyridone-2-carboxylic acid dimethylamide (L1) catalyzed direct C(sp2)-H (intra/intermolecular) arylation of unactivated arenes has been developed to expedite access to (Het)biaryl scaffolds under UV-irradiation at room temperature. The protocol tolerated diverse functional groups and substitution patterns, affording the target products in moderate to excellent yields. Mechanistic investigations were also carried out to better understand the reaction pathway. Furthermore, the synthetic applicability of this unified approach has been showcasedviathe construction of biologically relevant 4-quinolone, tricyclic lactam and sultam derivatives.
Decarbonylative Pd-Catalyzed Suzuki Cross-Coupling for the Synthesis of Structurally Diverse Heterobiaryls
Blakemore, David C.,Cervantes-Reyes, Alejandro,Chinigo, Gary M.,Smith, Aaron C.,Szostak, Michal
supporting information, p. 1678 - 1683 (2022/03/14)
Heteroaromatic biaryls are core scaffolds found in a plethora of pharmaceuticals; however, their direct synthesis by the Suzuki cross-coupling is limited to heteroaromatic halide starting materials. Here, we report a direct synthesis of diverse nitrogen-containing heteroaromatic biaryls by Pd-catalyzed decarbonylative Suzuki cross-coupling of widely available heterocyclic carboxylic acids with arylboronic acids. The practical and modular nature of this cross-coupling enabled the straightforward preparation of >45 heterobiaryl products using pyridines, pyrimidines, pyrazines, and quinolines in excellent yields. We anticipate that the modular nature of this protocol will find broad application in medicinal chemistry and drug discovery research.
Inhibition of (dppf)nickel-catalysed Suzuki-Miyaura cross-coupling reactions by α-halo-N-heterocycles
Burton, Paul M.,Cooper, Alasdair K.,Donohoe, William,Greaves, Megan E.,Kennedy, Alan R.,Nelson, David J.,Ronson, Thomas O.
, p. 14074 - 14082 (2021/11/12)
A nickel/dppf catalyst system was found to successfully achieve the Suzuki-Miyaura cross-coupling reactions of 3- and 4-chloropyridine and of 6-chloroquinoline but not of 2-chloropyridine or of other α-halo-N-heterocycles. Further investigations revealed that chloropyridines undergo rapid oxidative addition to [Ni(COD)(dppf)] but that α-halo-N-heterocycles lead to the formation of stable dimeric nickel species that are catalytically inactive in Suzuki-Miyaura cross-coupling reactions. However, the corresponding Kumada-Tamao-Corriu reactions all proceed readily, which is attributed to more rapid transmetalation of Grignard reagents.
