cas 3319-99-1, 2-(2-THIENYL)PYRIDINE | Articles data

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Palladium-catalyzed cross-coupling reactions of organomercurials with organic halides
Organomercurials, (A)2Hg (A = 5-methyl-2-furyl, thienyl) react with organic halides, ArI, in the presence of a palladium catalyst and iodide ion under argon to give cross-coupled products AAr, in high yields.
Bumagin, N. A.,More, P. G.,Beletskaya, I. P.
p. 231 - 234
(1989)
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Platinum and palladium complexes of thienylpyridine. I. Compounds containing metal-carbon bonds
Complexes of divalent platinum and palladium with 2-(2′-thienyl)pyridine (TP) have been investigated. In this paper we describe the syntheses and structures of those derivatives which form a metal-carbon σ bond by the spontaneous loss of a hydrogen from an aromatic group (TP-H). The reaction of TP with PtX42- (X = Br-, I-) yields orange crystalline Pt(TP)(TP-H)X. In these complexes, one TP acts as a monodentate N donor and the other as an N-C chelate, through the thienyl ring. A yellow, crystalline palladium analog Pd(TP)(TP-H)NO3 can be prepared by the reaction of TP with AgNO3 and PdI42-. All of these complexes are monomers and nonelectrolytes in nonpolar solvents. The crystal structure of iodo[2-(2′-thienyl)pyridine][2-(2′-thienyl)pyridyl]platinum(II) was determined from three-dimensional single-crystal X-ray diffraction data collected by counter methods. The complex Pt(C9H7NS)(C9H6NS)I was found to crystallize in the monoclinic space group P21/n with a = 17.360 (3) A?, b = 8.418 (1) A?, c = 13.556 (2) A?, β = 110.53 (2)° Z = 4 molecules/cell. The structure was refined by block diagonal and full matrix methods to a final R factor of 4.6% for 2220 nonzero reflections. The platinum atom is coordinated by two pyridyl nitrogens trans to one another, a thienyl carbon, and an iodide which lies slightly below the plane formed by the platinum and the other three coordinating atoms. The Pt-N distances are 2.04 (1) and 2.02 (1) A? for the nitrogens in the monodentate and the chelated ligands, respectively; the Pt-I and Pt-C distances are 2.68 (1) and 1.97 (2) A?, respectively. The free thiophene ring (not coordinated to the metal by a metal-carbon σ bond) is in an axial position. This ring was found to be disordered by 180° rotation about the pyridine-thiophene bond. The Pt-S distance (2.99 (3) A?) was nevertheless determined with reasonable accuracy and was found to be less than the sum of the van der Waals radii. The line between the platinum and the sulfur makes an angle of ca. 15° with the normal to the equatorial plane at the platinum site. The visible-ultraviolet spectra of these complexes resemble the spectra of five-coordinate d8 complexes and the ir spectra show a shifted thiophene band assigned to the thiophene ring in the axial position. These spectral results are interpreted with respect to metal-thiophene axial interaction. The metal to carbon σ bond forms with unusual ease under wet, aerobic conditions due to the thiophene ring reactivity and the chelate stability.
Giordano,Rasmussen, Paul G.
p. 1628 - 1634
(1975)
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Dual effect of halides in the stille reaction: In situ halide metathesis and catalyst stabilization
Halide anions can increase or decrease the transmetallation rate of the Stille reaction through in situ halide metathesis. Although the influence of the halogen present in oxidative addition complexes on the transmetallation rate with organostannanes was already known, the application of in situ halide metathesis to accelerate cross-coupling reactions with organometallic reagents is not described in the literature yet. In addition a second unprecedented role of halides was discovered. Halide anions stabilize the [Pd0(L) 2] catalyst in Stille reactions, by means of [Pd0X(L) 2]? formation (X=Cl, I), hereby preventing its leaching from the catalytic cycle. Both arene (iodobenzene) and azaheteroarene (2-halopyridine, halopyrazine, 2-halopyrimidine) substrates were used.
Verbeeck, Stefan,Meyers, Caroline,Franck, Philippe,Jutand, Anny,Maes, Bert U. W.
p. 12831 - 12837
(2010)
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Microwave-assisted palladium catalysed C-H acylation with aldehydes: Synthesis and diversification of 3-acylthiophenes
The use of MW allows the efficient palladium(ii)-catalysed C-3 acylation of thiophenes with aldehydes via C(sp2)-H activation for the synthesis of (cyclo)alkyl/aryl thienyl ketones (43 examples). Compared to standard thermal conditions, the use of MW redu
Jiménez-Aberasturi, Xabier,Leicea, Eztizen,Lete, Esther,Lete, Marta G.,Santiago, Carlos,Sotomayor, Nuria
supporting information
p. 852 - 861
(2022/02/03)

N- Heterocyclic carbene palladium complex with butterfly structure and application thereof (by machine translation)
N - Heterocyclic carbene palladium complex, with a butterfly structure prevents aromatic amine from encircling carbon-nitrogen bond upset, and in a steric hindrance C11 framework structure to inhibit C12 coupling reaction, between nitrogen-containing heterocyclic chlorine and low-activity nitrogen-containing heterocyclic boronic acid and reaction can be carried out β - under mild conditions of air and water at the same time to ensure higher reaction yield, The present invention also greatly improves the reaction activity, Suzuki - Miyaura of the catalyst. (by machine translation)
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Paragraph 0088-0098

(2020/05/30)

Multicomponent Aromatic and Benzylic Mannich Reactions through C?H Bond Activation
Multicomponent Mannich reactions through C?H bond activation are described. These transformations allowed for the straightforward generation of densely substituted benzylic and homo-benzylic amines in good yields. The reaction involves a reaction between two transient species: an organometallic species, generated by transition-metal-catalyzed sp2 or sp3 C?H bond activation and an in situ generated imine. The use of an acetal as an aldehyde surrogate was found essential for the reaction to proceed. The process could be successfully applied to RhIII-catalyzed sp2 C?H bond functionalization and extended to CuII-catalyzed sp3 C?H bond functionalization.
Xavier, Tania,Rayapin, Corinne,Le Gall, Erwan,Presset, Marc
supporting information
p. 13824 - 13828
(2019/11/03)

Theoretical and experimental characterization of 1,4-N?S σ-hole intramolecular interactions in bioactive N-acylhydrazone derivatives
Sigma-hole (σ-hole) bonds are interactions that are gaining special attention in medicinal chemistry. This type of interaction, initially assigned to the halogens (group 17 of the periodic table), has been extended to atoms of groups 14, 15 and 16. Sulfur atoms have been outstanding for describing these interactions at the intramolecular level (to induce conformational stability) and the intermolecular level (participating in molecular recognition of bioactive compounds by their respective targets). Thus, this work describes the theoretical and experimental characterization of a 1,4-N?S σ-hole intramolecular interaction in the N-acylhydrazone cardioactive prototype LASSBio-294 (1), which leads to conformational stabilization and has a direct influence on the molecular properties of this inotropic prototype compared to a negative control for the interaction, LASSBio-897 (2), which is the regioisomer at the thiophene ring. Our theoretical results were reached using the B3LYP/6-311G(d) level of theory, including analysis of conformational, orbital and electrostatic properties. We performed experimental studies using IR, Raman, UV and NMR spectroscopies, which corroborated our theoretical data, showing significant differences between LASSBio-294 (1) and LASSBio-897 (2) in relation to the bond strength of the groups involved in the N?S interaction (S-C and NC bonds), the energies of the orbitals associated with the S lone pair (Lp(S)) and the antibonding NC π bond (π?(NC)), as well as the 15N chemical shifts in both systems. Together, our results show how this unusual interaction can influence the molecular properties of some organic compounds.
Pinheiro, Pedro De Sena Murteira,Rodrigues, Daniel Alencar,Alves, Marina Amaral,Tinoco, Luzineide Wanderley,Ferreira, Glaucio Braga,De Sant'Anna, Carlos Mauricio Rabello,Fraga, Carlos Alberto Manssour
supporting information
p. 497 - 505
(2017/12/28)

Copper-catalyzed cross-coupling of aryl-, primary alkyl-, and secondary alkylboranes with heteroaryl bromides
A method for the Cu-catalyzed cross-coupling of both aryl and alkylboranes with aryl bromides is described. The method employs an inexpensive Cu-catalyst and functions for a variety of heterocyclic as well as electron deficient aryl bromides. In addition, aryl iodides of varying substitution patterns and electronic properties work well.
Bergmann, Allison M.,Oldham, Adam M.,You, Wei,Brown, M. Kevin
supporting information
p. 5381 - 5384
(2018/06/01)

Accessing Heterobiaryls through Transition-Metal-Free C-H Functionalization
Herein we report a transition-metal-free synthetic protocol for heterobiaryls, one of the most important pharmacophores in the modern drug industry, employing a new multidonor phenalenyl (PLY)-based ligand. The current procedure offers a wide substrate scope (24 examples) with a low catalyst loading resulting in an excellent product yield (up to 95%). The reaction mechanism involves a single electron transfer (SET) from a phenalenyl-based radical to generate a reactive heteroaryl radical. To establish the mechanism, we have isolated the catalytically active SET initiator, characterizing by a magnetic study.
Banik, Ananya,Paira, Rupankar,Shaw, Bikash Kumar,Vijaykumar, Gonela,Mandal, Swadhin K.
p. 3236 - 3244
(2018/03/23)

Method for synthesizing 2-(2-thiophene)pyridine
The invention relates to a method for synthesizing 2-(2-thiophene)pyridine. The method employs 2-cyano-thiophene and acetylene gas to generate 2-(2-thiophene)pyridine under conditions of 0.5 MPa-2.1 MPa and 110-210 DEG C and under catalysis effect of organic cobalt. The generated 2-(2-thiophene)pyridine is subjected to subsequent processing refining to obtain the 2-(2-thiophene)pyridine product with purity of 98% or more. The organic cobalt is selected from cobaltocene or dicyclopentadiene cobalt. The method has the advantages of simple process and strong operationality, and the prepared product has the advantages of high purity, high yield and stabilization.
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(2017/02/24)

Water based surfactant-assisted synthesis of thienylpyridines and thienylbipyridine intermediates
The connection between heterocyclic systems by forming new C[sbnd]C bond is a relevant topic for the easy preparation of intermediates and functional dyes for technological applications. Several methods were developed in the last decades and the urge for sustainable synthetic chemical methods pushed us to prepare thienylpyridines and two thienylbipyridine ligands by the Suzuki reaction in aqueous CTAB micellar medium and in presence of a Pd catalyst. These intermediates can be found as component of dyes and functional thiophene monomers. Reaction conditions were optimized under both thermal and microwave (MW) activation obtaining good yields (70–93%) using Pd(PPh3)4 as catalyst. Two thienylbipyridine ligands were prepared and the transformation of one of them into a terthiophene-based bipyridine ligand was easily obtained by almost green methods and with very good yield. This clean and sustainable method can be proposed as a green step to obtain intermediates and final dyes for technological applications, such as CO2 reduction, in gram-multigram scale.
Quagliotto,Barbero,Barolo,Buscaino,Carfora,Prosperini,Viscardi
p. 468 - 479
(2016/12/16)

Ru-Catalyzed Regioselective Direct Hydroxymethylation of (Hetero)Arenes via C-H Activation
An efficient and direct ruthenium-catalyzed regioselective hydroxymethylation of (hetero)arenes via C-H activation with paraformaldehyde as a hydroxymethylating reagent is described. The corresponding products can be obtained in good to excellent yield. A number of aryl aldehydes can also be used in place of paraformaldehyde giving the desired alcohol products with similarly good results.
Zhang, Guo-Fu,Li, Yue,Xie, Xiao-Qiang,Ding, Cheng-Rong
supporting information
p. 1216 - 1219
(2017/03/14)

Copper-mediated C-H cyanation of (hetero)arenes with ethyl (ethoxymethylene)cyanoacetate as a cyanating agent
A copper-mediated direct C-H cyanation of (hetero)arenes with ethyl (ethoxymethylene)cyanoacetate as a safe cyanating agent has been successfully developed by using molecular oxygen as the oxidant. The reaction tolerates a variety of functional groups and provides a facile and efficient method for the synthesis of a wide range of (hetero)aryl nitriles.
Qi, Chaorong,Hu, Xiaohan,Jiang, Huanfeng
p. 7994 - 7997
(2017/07/22)

A Micellar Catalysis Strategy for Suzuki-Miyaura Cross-Couplings of 2-Pyridyl MIDA Boronates: No Copper, in Water, Very Mild Conditions
Suzuki-Miyaura (SM) cross-couplings of 2-pyridyl MIDA boronates can be successfully carried out in the complete absence of copper by attenuation of the Lewis basicity associated with the pyridyl nitrogen using selected substituents (e.g., fluorine or chlorine) on the ring. This strategy imparts additional synthetic options compared with existing approaches based on the use of Lewis acids or N-oxides. Thus, access to highly valued 2-substituted pyridyl rings via an initial Suzuki-Miyaura coupling can be followed by dehalogenation, SNAr reactions, or a second SM coupling to arrive at 2,6-disubstituted pyridyl arrays, all run in a single pot, enabled by micellar catalysis in water. Accessing targets within drug-like space is demonstrated in a four-step, one-pot sequence. Computational data suggest that the major role being played by electron-withdrawing substituents in promoting these cross-couplings without the need for copper is to slow the rates of protodeboronation of intermediate 2-pyridylboronic acids.
Isley, Nicholas A.,Wang, Ye,Gallou, Fabrice,Handa, Sachin,Aue, Donald H.,Lipshutz, Bruce H.
p. 8331 - 8337
(2017/12/08)

Cobalt-Catalyzed Cross-Coupling Reactions of Arylboronic Esters and Aryl Halides
An efficient cobalt catalyst system for the Suzuki-Miyaura cross-coupling reaction of arylboronic esters and aryl halides has been identified. In the presence of cobalt(II)/terpyridine catalyst and potassium methoxide, a diverse array of (hetero)biaryls have been prepared in moderate to excellent yields.
Duong, Hung A.,Wu, Wenqin,Teo, Yu-Yuan
supporting information
p. 4363 - 4366
(2017/12/05)

The design and synthesis of thiophene-based ruthenium(II) complexes as promising sensitizers for dye-sensitized solar cells
A new series of promising synthetically facile cycloruthenated thiophene-based sensitizers have been developed and fully characterized by UV–vis spectroscopy, NMR and cyclic voltammetric studies. The synthesized dyes have broad MLCT bands spanning the visible spectrum, with high extinction coefficients. The energies of the molecular orbitals for the isolated molecules of the complexes and densities of occupied states were determined. The cycloruthenated compounds contains ortho-metallated thiophene moiety substituted by N-(methyliden)aniline or pyridine-2-yl at the ortho-position. Having 4,4’-dicarboxy-2,2’-bipyridine as the linker and auxiliary ligands and anchored to nanocrystalline TiO2 films, they achieve efficient sensitization in the visible range and display an overall conversion efficiency of 5.3% under standard AM 1.5 sunlight.
Medved'ko,Ivanov,Kiskin,Sadovnikov,Apostolova,Grinberg,Emets,Chizhov,Nikitin,Magdesieva,Kozyukhin
p. 169 - 178
(2017/02/05)

Sequential one pot double C[sbnd]H heteroarylation of thiophene using bromopyridines to synthesize unsymmetrical 2,5-bipyridylthiophenes
We present C[sbnd]H heteroarylation reactions between thiophene and variously substituted bromopyridines. The objective was to synthesize unsymmetrical 2,5-bipyridylthiophenes. We studied the reaction conditions allowing to a sequential one-pot double C[sbnd]H heteroarylation, in a view to introduce two different pyridyl moieties at positions 2 and 5 of the thiophene ring using bromopyridines. 11 original unsymmetrical 2,5-bipyridylthiophenes were synthesized and characterized, including 2,5-di(pyridin-2-yl)thiophenes for which the preparation by classical cross-coupling reactions is challenging. Finally, with the additional synthesis of both an unsymmetrical 2,5-biarylthiophene and an original pyrimidin-thiophene-furan scaffold, we shown that our methodology was also an efficient tool to access to new heterocyclic sequences.
Kieffer, Charline,Babin, Victor,Jouanne, Marie,Slimani, Ikram,Berhault, Yohann,Legay, Rémi,Sopková-de Oliveira Santos, Jana,Rault, Sylvain,Voisin-Chiret, Anne Sophie
p. 5509 - 5516
(2017/08/22)

β-Strand Mimicry: Exploring Oligothienylpyridine Foldamers
Protein–protein interactions (PPIs) are involved in many cellular processes; consequently, the discovery of small molecules as modulators of PPIs has become an important challenge in medicinal chemistry. Structural mimetics of α-helices, β-turns or β-strands could maintain or restore biological functions and should possess biological activity. At this time, the most challenging classes of PPIs are those mediated by β-sheet interactions, which are implicated in a number of diseases. Only a few β-strand mimics have been published to date. This study presents an evaluation of oligothienylpyridyl scaffolds in view of their ability for β-strand mimicry. In this study, theoretical ring twist angle predictions for these scaffolds have been validated by X-ray diffraction and molecular dynamics simulations with NMR constraints. Careful choice of substituent and heavy-atom positions in the foldamer units opens the way to produce reasonably coplanar compounds mimicking β-strand side-chain distribution.
Jouanne, Marie,Voisin-Chiret, Anne Sophie,Legay, Rémi,Coufourier, Sébastien,Rault, Sylvain,Sopkova-de Oliveira Santos, Jana
p. 5686 - 5696
(2016/12/14)

Palladium catalyzed ortho-C-H-acylation of 2-arylpyridines using phenylacetylenes and styrene epoxide
A palladium-catalyzed ortho-C-H-acylation of 2-arylpyridine using phenylacetylenes and styrene epoxide as the acylated reagents was developed. With the employment of tert-butyl hydroperoxide (TBHP) as the oxidant and a phosphorous ligand, the protocol generates corresponding aryl ketones in moderated to good yields with high regioselectivity and good functional group compatibility.
Zhang, Qian,Wang, Yang,Yang, Tingting,Li, Li,Li, Dong
supporting information
p. 90 - 94
(2015/12/23)

Comparative Catalytic Activity of Group 9 [CpMIII] Complexes: Cobalt-Catalyzed C-H Amidation of Arenes with Dioxazolones as Amidating Reagents
A procedure for the [CpCoIII]-catalyzed direct C-H amidation of arenes with dioxazolone has been developed. This reaction proceeds under straightforward and mild conditions with a broad range of substrates, including anilides. A comparative study on the catalytic activity of Group 9 [{CpMCl2}2] complexes revealed the unique efficiency of the cobalt catalyst. Pick of the bunch: A variety of arenes, including anilides, underwent direct C-H amidation with dioxazolones in the presence of a cobalt catalyst with a Cp? ligand under mild and straightforward reaction conditions (see scheme; Piv=pivaloyl). A comparative study of Group 9 [CpMIII] complexes revealed the unique ability of the cobalt catalyst to promote this transformation efficiently.
Park, Juhyeon,Chang, Sukbok
supporting information
p. 14103 - 14107
(2016/01/25)

Cobalt-catalyzed C-H cyanation of (Hetero)arenes and 6-Arylpurines with N -cyanosuccinimide as a new cyanating agent
A cobalt-catalyzed C-H cyanation reaction of arenes has been developed using N-cyanosuccinimide as a new electrophilic cyanating agent. The reaction proceeds with high selectivity to afford monocyanated products with excellent functional group tolerance. Substrate scope was found to be broad enough to include a wide range of heterocycles including 6-arylpurines.
Pawar, Amit B.,Chang, Sukbok
supporting information
p. 660 - 663
(2015/03/04)

Palladium catalyzed ortho-C-H-benzoxylation of 2-arylpyridines using iodobenzene dibenzoates
A palladium-catalyzed ortho-C-H-benzoxylation of 2-arylpyridines using iodobenzene dibenzoates has been developed. The reaction employed the stable and easily accessible hypervalent iodine reagents as both benzoxylate source and oxidant which made the protocol simple and facile. It showed high regioselectivity and good functional group tolerance, and gave the mono-benzoxylation products in moderate to excellent yields.
Zhang, Qian,Wang, Ying,Yang, Tingting,Li, Li,Li, Dong
supporting information
p. 6136 - 6141
(2015/10/28)

Application of organoselenides in the Suzuki, Negishi, Sonogashira and Kumada cross-coupling reactions
We reported herein the regio- and stereoselective palladium-catalyzed cross-coupling reactions of unsaturated organoselenides with Sonogashira, Suzuki, Negishi and Kumada partners. The reactions were in general carried out with Pd(PPh3)4 (10 mol%), in DMF at 80 °C to afford the cross-coupling products in good yields. This strategy tolerated a wide range of substrates, such as alkynyl, vinyl, aryl and heteroaryl selenides with a variety of sensitive functional groups and gave the cross-coupling products in good yields.
Stein,Bilheri,Zeni
supporting information
p. 15522 - 15525
(2015/10/28)

Reusable, highly active heterogeneous palladium catalyst by convenient self-encapsulation cross-linking polymerization for multiple carbon-carbon cross-coupling reactions at ppm to ppb palladium loadings
Designing reusable high-performance heterogeneous palladium (Pd) catalysts via convenient, economic synthesis is of great importance to the industrial applications of various carbon-carbon crosscoupling reactions. We demonstrate herein a convenient one-pot self-encapsulation synthesis of a heterogeneous Pd catalyst [Pd@PDEB, PDEB = poly(1,3-diethynylbenzene)] directly from commercially available, economic precursors. In the synthesis, the formation of the cross-linked polymer networks and Pd encapsulation are accomplished simultaneously, turning a homogeneous Pd polymerization catalyst into the heterogeneous cross-coupling catalyst. As a unique, practical heterogeneous catalyst, Pd@PDEB shows remarkably high activity, high reusability, and high versatility towards at least four types of cross-coupling reactions (Suzuki-Miyaura, Stille, allylic arylation, and Mizoroki-Heck reactions) with even difficult reactants (aryl chlorides and heteroaryl halides) under aerobic conditions with Pd loadings down to ppm or even ppb levels. Evidences from hot filtration and 3-phase tests demonstrate the heterogeneous nature of the catalyst with very low Pd leaching and negligible contributions of leached homogeneous Pd species towards the coupling reactions.
Donga, Zhongmin,Yea, Zhibin
p. 3401 - 3414
(2015/02/05)

Synthesis of heteroaryl compounds through cross-coupling reaction of aryl bromides or benzyl halides with thienyl and pyridyl aluminum reagents
An efficient method for synthesis of useful biaryl building blocks containing 2-thienyl, 3-thienyl, 2-pyridyl, and 3-pyridyl moieties was provided through cross-coupling reactions of aryl bromides or benzyl halides with heteroaryl aluminum reagents in the presence of Pd(OAc)2 and (o-tolyl)3P. The coupling reaction also worked efficiently with heteroaryl bromides affording series of heterobiaryl compounds. The reaction of phenylbromide with in situ prepared 3-pyridyl aluminum was demonstrated to afford the product 8a in high yield. Additionally, the catalytic system was also suited well for the coupling reaction of benzyl halides with pyridyl aluminum reagents to afford series of pyridyl-arylmethane.
Chen, Xu,Zhou, Lingmin,Li, Yimei,Xie, Tao,Zhou, Shuangliu
p. 230 - 239
(2014/01/17)

A general catalyst for Suzuki-Miyaura and Sonogashira reactions of aryl and heteroaryl chlorides in water
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.
Peng, Hui,Chen, Ya-Qin,Mao, Shu-Lan,Pi, Yun-Xiao,Chen, You,Lian, Ze-Yu,Meng, Tong,Liu, Sheng-Hua,Yu, Guang-Ao
supporting information
p. 6944 - 6952
(2014/09/29)

Regioselective ruthenium-catalyzed carbonylative direct arylation of five-membered and condensed heterocycles
A ruthenium-catalyzed carbonylative Ci￡H bond arylation process for the three-component synthesis of complex aryl-(hetero)aryl ketones in an aqueous solution has been developed. By exploiting the ortho-activating effect of nitrogen-containing directing groups, a regioselective, successive twofold C(sp2)i￡C(sp2) bond formation has been achieved. This straightforward catalytic process provides access to versatile products prevalent in multiple bioactive compounds and supplies a valuable functional group for subsequent transformations. Ci￡ H bond functionalization: A ruthenium-catalyzed carbonylative Ci￡H bond arylation process for the three-component synthesis of complex aryl-(hetero)aryl ketones in an aqueous solution has been developed (see scheme). By exploiting the ortho-activating effect of nitrogen-containing directing groups, a regioselective, successive twofold C(sp2) i￡C(sp2) bond formation has been achieved.
Pospech, Jola,Tlili, Anis,Spannenberg, Anke,Neumann, Helfried,Beller, Matthias
supporting information
p. 3135 - 3141
(2014/03/21)

General suzuki coupling of heteroaryl bromides by using tri-tert-butylphosphine as a supporting ligand
A general procedure for the fast Suzuki coupling of major families of heteroaryl bromides was realized by using Pd(OAc)2/PtBu3 as the catalyst. Many couplings were finished within minutes at room temperature in n-butanol. Different from previous studies, three typical heteroaryl bromides were systematically examined in couplings of various heteroaryl and aryl boronic acids. A fast, general coupling of heteroaryl bromides is realized by using a single palladium catalyst supported by tri-tert-butylphosphine.
Zou, Yinjun,Yue, Guizhou,Xu, Jianwei,Zhou, Jianrong
supporting information
p. 5901 - 5905
(2015/03/30)

Rapid microwave-assisted sol-gel preparation of Pd-substituted LnFeO 3 (Ln = Y, La): Phase formation and catalytic activity
We present a rapid microwave-assisted sol-gel approach to Pd-substituted LnFeO3 (Ln = Y, La) for applications in C-C coupling reactions. These materials could be prepared in household microwave ovens in less than 15 minutes of reaction time with the final materials displaying well-defined structure and morphology. Phase evolution was studied using time-dependent microwave heatings and then compared with the results obtained from thermogravimetric analyses. Materials were confirmed to be phase pure by laboratory and synchrotron X-ray diffraction. Substituted Pd is ionic as shown by the binding energy shift from X-ray photoelectron spectroscopy. The short heating periods required for phase purity allow these materials less time for sintering as compared to conventional solid state preparation methods, making relatively high surface areas achievable. These materials have been successfully used as catalyst precursor materials for C-C coupling reactions in which the active species is Pd0. Pd-substituted LnFeO3 (Ln = Y, La) provides Pd0 in solution which can be complexed by the ligand SPhos, allowing for aryl chloride coupling.
Misch, Lauren M.,Birkel, Alexander,Figg, C. Adrian,Fors, Brett P.,Hawker, Craig J.,Stucky, Galen D.,Seshadri, Ram
supporting information
p. 2079 - 2087
(2014/01/17)

Palladacycle-catalyzed Suzuki-Miyaura reaction of aryl/heteroaryl halides with MIDA boronates in EtOH/H2O or H2O
With good to excellent yields, a series of mono- or diheteroaryl compounds were synthesized via the palladacycle-catalyzed Suzuki-Miyaura reaction of various N-methyliminodiacetic acid (MIDA) boronates with aryl/heteroaryl halides in EtOH/H2O or H2O. This journal is the Partner Organisations 2014.
Li, Yabo,Wang, Jingran,Wang, Zhiwei,Huang, Mengmeng,Yan, Beiqi,Cui, Xiuling,Wu, Yusheng,Wu, Yangjie
p. 36262 - 36266
(2014/11/08)

Silyl-protected dioxaborinanes: Application in the Suzuki cross-coupling reaction
The synthesis of a range of novel silyl-protected dioxaborinanes as a column- and bench-stable boron reagent were found to be advantageous to achieving good yields in palladium-catalysed cross-coupling reactions under standard conditions. This journal is The Royal Society of Chemistry.
Goggins, Sean,Rosevere, Eleanor,Bellini, Clement,Allen, Joseph C.,Marsh, Barrie J.,Mahon, Mary F.,Frost, Christopher G.
supporting information
p. 47 - 52
(2014/01/06)

Synthesis of solid 2-pyridylzinc reagents and their application in Negishi reactions
In search of alternatives to unstable or unreliable 2-pyridylboron reagents, we have explored two new varieties of solid, moderately air-stable 2-pyridylzinc reagents. Both reagents can be manipulated in air and are competent nucleophiles in Negishi cross-coupling reactions.
Colombe, James R.,Bernhardt, Sebastian,Stathakis, Christos,Buchwald, Stephen L.,Knochel, Paul
supporting information
p. 5754 - 5757
(2013/12/04)

Direct heteroarylation of 5-bromothiophen-2-ylpyridine and of 8-bromoquinoline via palladium-catalysed C-H bond activation: Simpler access to heteroarylated nitrogen-based derivatives
The palladium-catalysed direct heteroarylation of the pyridyl-containing substrates, 2-(5-bromothiophen-2-yl)pyridine and 8-bromoquinoline, proceeds in moderate to high yields with a variety of heteroarenes in the presence of 1-2 mol% of a palladium catalyst. This approach allows the access to polyheteroaromatics which are interesting building blocks as (NC)-chelate ligands. The reaction proceeds regioselectively at the C5 position of thiophenes, thiazoles, furans or pyrroles and tolerates various substituents such as formyl, acetyl, ester, nitrile or chloro on the heteroarene. Therefore, this method allows a straightforward modulation of the electron density distribution on such derivatives.
Laroche, Jenny,Beydoun, Kassem,Guerchais, Veronique,Doucet, Henri
p. 2072 - 2080
(2013/07/26)

Copper-catalyzed dehydrogenative coupling of arenes with alcohols
What a couple! Arenes functionalized with donating groups undergo oxidative dehydrogenative coupling with alcohols in the presence of a copper/silver catalyst system. This intermolecular C-H alkoxylation provides a convenient synthetic route to the important class of aryl ethers. The catalyst system also allows the alkoxylation of benzylic C-H groups with formation of benzyl alkyl ethers. Copyright
Bhadra, Sukalyan,Matheis, Christian,Katayev, Dmitry,Goo?en, Lukas J.
p. 9279 - 9283
(2013/09/12)

Copper-catalyzed Hiyama coupling of (hetero)aryltriethoxysilanes with (hetero)aryl iodides
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.
Gurung, Santosh K.,Thapa, Surendra,Vangala, Adarsh S.,Giri, Ramesh
supporting information
p. 5378 - 5381
(2013/11/06)

Mn-catalyzed aromatic C-H alkenylation with terminal alkynes
The first manganese-catalyzed aromatic C-H alkenylation with terminal alkynes is described. The procedure features an operationally simple catalyst system containing commercially available MnBr(CO)5 and dicyclohexylamine (Cy2NH). The reaction occurs readily in a highly chemo-, regio-, and stereoselective manner delivering anti-Markovnikov E-configured olefins in high yields. Experimental study and DFT calculations reveal that (1) the reaction is initiated by a C-H activation step via the cooperation of manganese and base; (2) manganacycle and alkynylmanganese species are the key reaction intermediates; and (3) the ligand-to-ligand H-transfer and alkynyl-assisted C-H activation are the key steps rendering the reaction catalytic in manganese.
Zhou, Bingwei,Chen, Hui,Wang, Congyang
supporting information
p. 1264 - 1267
(2013/03/14)

Cross-coupling of aryllithiums with aryl and vinyl halides in flow microreactors
The use of Pd catalysts that contained a carbene ligand, such as PEPPSI-SIPr, speeded up the Murahashi coupling of ArLi with ArBr, by enabling its integration with the Br/Li exchange of ArBr with BuLi in flow. Space integration realized the rapid cross-coupling of two different ArBr substrates. However, the cross-coupling reaction with vinyl halides could not be achieved under similar conditions. Pd(OAc)2 was an effective catalyst, and the space integration of the Br/Li exchange of ArBr with BuLi and the Murahashi coupling with vinyl halides was successfully achieved.
Nagaki, Aiichiro,Moriwaki, Yuya,Haraki, Suguru,Kenmoku, Akira,Takabayashi, Naofumi,Hayashi, Atsushi,Yoshida, Jun-Ichi
supporting information; experimental part
p. 1061 - 1068
(2012/07/31)

Highly reactive, single-component nickel catalyst precursor for Suzuki-Miyuara cross-coupling of heteroaryl boronic acids with heteroaryl halides
One for all: The coupling of a range of nitrogen- and sulfur-containing heteroaryl halides with five-membered nitrogen-, oxygen-, and sulfur-containing heteroaryl boronic acids were achieved in high yields with only 0.5 mol % of the single-component nickel precatalyst [(dppf)NiCl(cinnamyl)] (dppf=1,1′- bis(diphenylphosphanyl)ferrocene). The reaction demonstrates good functional group compatibility, and is easily conducted on a large scale without a dry box. Copyright
Ge, Shaozhong,Hartwig, John F.
supporting information
p. 12837 - 12841
(2013/02/22)

Oxidative addition of heteroaromatic halides to Negishi reagent and subsequent cross-coupling reactions
Heteroarylzirconocene halides were prepared via the oxidative addition of heteroaryl halides to the Negishi reagent 'Cp2ZrBu2'. The palladium-catalyzed cross-coupling of the in situ generated organozirconium reagents with functionali
Harris, Caleb F.,Ravindranathan, Deepak,Huo, Shouquan
supporting information
p. 5389 - 5392
(2012/10/29)

Iron-catalyzed C-H bond activation for the ortho-arylation of aryl pyridines and imines with Grignard reagents
Direct arylation of the ortho-C-H bond of an aryl pyridine or an aryl imine with an aryl Grignard reagent has been achieved by using an iron-diamine catalyst and a dichloroalkane as an oxidant in a short reaction time (e.g., 5 min) under mild conditions (0 °C). The use of an aromatic co-solvent, such as chlorobenzene and benzene, and slow addition of the Grignard reagent are essential for the high efficiency of the reaction. The present arylation reaction has distinct merits over the previously developed reaction that used an arylzinc reagent, such as its reaction rate and atom economy. Selective C-H bond activation occurs in the presence of a leaving group, such as a tosyloxy, chloro, and bromo group. Studies on a stoichiometric reaction and kinetic isotope effects shed light on the reaction intermediate and the C-H bond-activation step.
Yoshikai, Naohiko,Asako, Sobi,Yamakawa, Takeshi,Ilies, Laurean,Nakamura, Eiichi
supporting information; experimental part
p. 3059 - 3065
(2012/07/13)

PdCl2(dppf)-catalyzed in situ coupling of 2-hydroxypyridines with aryl boronic acids mediated by PyBroP and the one-pot chemo- and regioselective construction of two distinct aryl-aryl bonds
We present a PdCl2(dppf)-catalyzed synthesis of 2-arylated pyridine derivatives via the in situ coupling of 2-OH pyridines and boronic acids mediated by PyBroP. In addition, the highly chemo- and regioselective construction of two different aryl-aryl bonds via a one-pot operation has also been demonstrated by the orthogonal use of this method with the Ni-catalyzed Suzuki-Miyaura coupling of phenols.
Li, Shui-Ming,Huang, Jie,Chen, Guo-Jun,Han, Fu-She
supporting information; experimental part
p. 12840 - 12842
(2012/01/05)

Palladium on charcoal-catalyzed ligand-free Stille coupling
An efficient ligand-free Stille coupling reaction catalyzed by palladium on charcoal was developed. Tetraphenyltin was reacted with a variety of aryl halides including aryl chlorides using LiCl as an additive. The reactions of tributyl organotin compounds with aryl iodides were effectively expedited by the addition of LiF. These reactions efficiently proceeded without a phosphine or arsenic ligand and no leached palladium was detected in the reaction mixture.
Yabe, Yuki,Maegawa, Tomohiro,Monguchi, Yasunari,Sajiki, Hironao
experimental part
p. 8654 - 8660
(2010/11/19)

CATALYST COMPOSITION AND PROCESS FOR PRODUCING CROSS-COUPLED COMPOUND USING SAME
A catalyst composition for a cross-coupling reaction comprising a nickel metal source, a fluorine source, and a nitrogen-containing heterocyclic compound having a specific structure, or a phosphine compound. Using this catalyst composition, a cross-coupled compound R5—R6 (wherein R5 and R6 are an aryl or heteroaryl group, or a linear, branched or cyclic alkyl group or a linear, branched or cyclic alkenyl group) is produced with a high selectivity by allowing an organometallic compound of the formula (2) R5-MY1 or the formula (3) R5-M-R5 (wherein R5 is the same as defined above, M is a Mg or Zn atom, and Y1 is a halogen atom) to react with a compound of the formula (4) R6—Y2 (wherein R6 is the same as defined above, and Y2 is a halogen atom, a methanesulfonate group, a toluenesulfonate group or a trifluoromethanesulfonate group).
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Page/Page column 9; 11

(2010/08/07)

Cross-coupling in a flow microreactor: Space integration of lithiation and murahashi coupling
Going with the flow: The use of palladium catalysts bearing a carbene ligand resulted in a faster Murahashi coupling, and enabled its integration with the Br-Li exchange of ArBr with Bu-Li in a microreactor (see picture). This system allows the cross-coupling of two different arylbromides within a minute without necessitating low temperatures (-78°C).
Nagaki, Aiichiro,Kenmoku, Akira,Moriwaki, Yuya,Hayashi, Atsushi,Yoshida, Jun-Ichi
supporting information; experimental part
p. 7543 - 7547
(2010/12/19)

Deprotonative metalation of substituted benzenes and heteroaromatics using amino/alkyl mixed lithium-zinc combinations
Different homoleptic and heteroleptic lithium-zinc combinations were prepared, and structural elements obtained on the basis of NMR spectroscopic experiments and DFT calculations. In light of their ability to metalate anisole, pathways were proposed to justify the synergy observed for some mixtures. The best basic mixtures were obtained either by combining ZnCl 2·TMEDA (TMEDA = N,N,N',N'tetramethylethylenediamine) with [Li(tmp)] (tmp = 2,2,6,6-tetramethylpiperidino; 3 equiv) or by replacing one of the tmp in the precedent mixture with an alkyl group. The reactivity of the aromatic lithium zincates supposedly formed was next studied, and proved to be substrate-, base-, and electrophile-dependent. The aromatic lithium zincates were finally involved in palladium-catalyzed cross-coupling reactions with aromatic chlorides and bromides.
Snegaroff, Katia,Komagawa, Shinsuke,Chevallier, Floris,Gros, Philippe C.,Golhen, Stephane,Roisnel, Thierry,Uchiyama, Masanobu,Mongin, Florence
experimental part
p. 8191 - 8201
(2010/09/11)

2-Pyridyl and 3-pyridylzinc bromides: direct preparation and coupling reaction
A facile synthetic approach to the direct preparation of 2-pyridyl and 3-pyridylzinc bromides has been demonstrated using Rieke zinc with 2-bromopyridine and 3-bromopyridine, respectively. A variety of different electrophiles have been coupled with the resulting organozinc reagents to give the corresponding cross-coupling products in moderate to good yields.
Kim, Seung-Hoi,Rieke, Reuben D.
scheme or table
p. 3135 - 3146
(2010/06/13)

Synthesis, photophysics, and electrochemistry of thiophene-pyridine and thiophene-pyrimidine dyad comonomers
A series of new π-conjugated donor (D) and acceptor (A) dyad comonomers were prepared using Suzuki coupling protocols. The D-A comonomers consisting of thiophene/bithiophene as donors and pyridine/pyrimidine as acceptors were prepared to investigate their photophysical and electrochemical properties. The dyads were spectroscopically confirmed to be highly conjugated. This was further supported by the X-ray crystal structure of the bithophene-pyridine dyad that showed all the heterocycles to be coplanar. It was further found that the fluorescence yields (Φfl) of die dyads were highly dependent on the number of thiophenes. The bithiophene derivatives exhibited Φfl values ≥ 0.3 while die thiophene derivatives did not fluoresce. The suppressed fluorescence observed for me thiophene derivatives was due to tiieir higher triplet energy resulting in efficient intersystem crossing (ISC) to the triplet state with ΦISC ≥ 0.8. This was confirmed both by time-resolved and steady-state measurements. The singlet excited state of both thiophene and bithiophene dyads was deactivated solely by either fluorescence and (or) ISC. Owing to their donor and acceptor character, die dyads could be oxidized and reduced both electrochemically and photochemically to afford the radical cation and anion, respectively.
Bolduc, Andreanne,Dufresne, Stephane,Hanan, Garry S.,Skene
experimental part
p. 236 - 246
(2010/06/17)

A mild negishi cross-coupling of 2-heterocyclic organozinc reagents and aryl chlorides
A mild Negishi cross-coupling of 2-heterocyclic organozinc reagents and aryl chlorides is described. The use of Pd2(dba)3 and X-Phos as a ligand provides high yields for many examples. An efficient method to generate the organozinc reagents at room temperature is also demonstrated.
Luzung, Michael R.,Patel, Jigar S.,Yin, Jingjun
supporting information; experimental part
p. 8330 - 8332
(2011/03/17)

Cobalt-catalyzed hydroarylation of alkynes through chelation-assisted C-H bond activation
Ternary catalytic systems consisting of cobalt salts, phosphine ligands, and Grignard reagents promote addition of arylpyridines and imines to unactivated internal alkynes with high regio- and stereoselectivities. Deuterium-labeling experiments suggest that the reaction involves chelation-assisted oxidative addition of the aryl C-H bond to the cobalt center and insertion of the C-C triple bond into the Co-H bond, followed by reductive elimination of the resulting diorganocobalt species.
Gao, Ke,Lee, Pin-Sheng,Fujita, Takeshi,Yoshikai, Naohiko
supporting information; experimental part
p. 12249 - 12251
(2010/11/18)

Highly selective biaryl cross-coupling reactions between aryl halides and aryl Grignard reagents: A new catalyst combination of N-heterocyclic carbenes and iron, cobalt, and nickel fluorides
Combinations of N-heterocyclic carbenes (NHCs) and fluoride salts of the iron-group metals (Fe, Co, and Ni) have been shown to be excellent catalysts for the cross-coupling reactions of aryl Grignard reagents (Ar1MgBr) with aryl and heteroaryl halides (Ar2X) to give unsymmetrical biaryls (Ar1-Ar2). Iron fluorides in combination with SIPr, a saturated NHC ligand, catalyze the biaryl cross-coupling between various aryl chlorides and aryl Grignard reagents in high yield and high selectivity. On the other hand, cobalt and nickel fluorides in combination with IPr, an unsaturated NHC ligand, exhibit interesting complementary reactivity in the coupling of aryl bromides or iodides; in contrast, with these substrates the iron catalysts show a lower selectivity. The formation of homocoupling byproducts is suppressed markedly to less than 5% in most cases by choosing the appropriate metal fluoride/NHC combination. The present catalyst combinations offer several synthetic advantages over existing methods: practical synthesis of a broad range of unsymmetrical biaryls without the use of palladium catalysts and phosphine ligands. On the basis of stoichiometric control experiments and theoretical studies, the origin of the unique catalytic effect of the fluoride counterion can be ascribed to the formation of a higher-valent heteroleptic metalate [Ar1MF2]MgBr as the key intermediate in our proposed catalytic cycle. First, stoichiometric control experiments revealed the stark differences in chemical reactivity between the metal fluorides and metal chlorides. Second, DFT calculations indicate that the initial reduction of di- or trivalent metal fluoride in the wake of transmetalation with PhMgCl is energetically unfavorable and that formation of a divalent heteroleptic metalate complex, [PhMF2]MgCl (M ) Fe, Co, Ni), is dominant in the metal fluoride system. The heteroleptic ate-complex serves as a key reactive intermediate, which undergoes oxidative addition with PhCl and releases the biaryl cross-coupling product Ph-Ph with reasonable energy barriers. The present crosscoupling reaction catalyzed by iron-group metal fluorides and an NHC ligand provides a highly selective and practical method for the synthesis of unsymmetrical biaryls as well as the opportunity to gain new mechanistic insights into the metal-catalyzed cross-coupling reactions.
Hatakeyama, Takuji,Hashimoto, Sigma,Ishizuka, Kentaro,Nakamura, Masaharu
supporting information; experimental part
p. 11949 - 11963
(2009/12/08)

A facile synthetic route for 2-pyridyl derivatives: direct preparation of a stable 2-pyridylzinc bromide and its copper-free and pd-catalyzed coupling reactions
Direct preparation of 2-pyridylzinc bromide has been developed. Interestingly, the subsequent coupling reactions with acid chlorides have been carried out without any transition metal catalyst. 2-Pyridylaryl compounds, symmetrical and unsymmetrical 2,2′-b
Kim, Seung-Hoi,Rieke, Reuben D.
supporting information; experimental part
p. 5329 - 5331
(2009/12/06)

A facile synthetic approach to the preparation of 3-pyridyl derivatives: Preparations and coupling reactions of 3-pyridylzinc and its analogues
A facile synthetic approach to the direct preparation of 3pyridylzinc bromide has been demonstrated using Rieke zinc with 3-bromopyridine in the presence of a catalytic amount of lithium chloride. A variety of different electrophiles have been coupled to give the corresponding cross-coupling products in moderate to good yields. Also, this methodology has been expanded to the preparation of the corresponding organozinc reagents of 3-bromopyridine analogues. Georg Thieme Verlag Stuttgart.
Kim, Seung-Hoi,Slocum, Tim B.,Rieke, Reuben D.
scheme or table
p. 3823 - 3827
(2010/03/04)