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Arylation
Kinds of Arylation Terms modified by Arylation Selected AbstractsArylation of Hydrocarbyl Ligands Formed from n -Alkanes through C,H Bond Activation of Benzene Using a Triruthenium ClusterEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 23 2009Makoto Moriya Abstract Triruthenium complex 2 containing a perpendicularly coordinated 1-pentyne ligand, which is one of the key intermediates of the reaction of triruthenium pentahydrido complex 1 with n -pentane, reacts with benzene to yield ,3 -benzyne,,3 -pentylidyne complex 5 by C,H bond activation. ,-H elimination form the ,3 -penytylidyne ligand occurred upon heating to yield ,3 -pentenylidene complex 6, which was followed by the formation of closo -ruthenacyclopentadiene complex 8 by the connection of the two hydrocarbyl moieties placed on each face of the triruthenium plane with partial metal,metal bond breaking. Treatment of 8 with pressurized hydrogen resulted in exclusive liberation of n -pentylbenzene, which is difficult to synthesize by conventional Friedel,Crafts alkylation. These sequential transformations correspond to the formation of linear alkylbenzene by the reaction of pentane with benzene on a trimetallic plane. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] 2-Substituted Benzo[b]furans from (E)-1,2-Dichlorovinyl Ethers and Organoboron Reagents: Scope and Mechanistic Investigations into the One-Pot Suzuki Coupling/Direct Arylation,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2010Laina M. Geary Abstract 2-Substituted benzo[b]furans can easily be assembled from simple phenols, boronic acids or other organoboron reagents, and trichloroethylene. The overall process requires only two synthetic steps, with the key step being a one-pot sequential Suzuki cross-coupling/direct arylation reaction. The method tolerates many useful functional groups and does not require the installation of any other activating functionality. The modular nature of the process permits the rapid synthesis of many analogues using essentially the same chemistry, of particular value in drug development. Results of kinetic isotope effect studies and investigations into the regioselectivity of the process indicate that the direct arylation step most likely does not involve an electrophilic palladation. The most likely mechanism lies somewhere on the continuum between a C,H bond metathesis and an assisted palladation or concerted metallation-deprotonation pathway. [source] Chiral Triphenylprolinol Ligands for the Efficient Catalytic Asymmetric Arylation of AldehydesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2010Angélica Venturini Moro Abstract The synthesis of new chiral amino alcohols by Heck arylation of an enecarbamate is described. These compounds were used as chiral ligands for the catalytic asymmetric arylation of aldehydes and can be easily recovered. Chiral, nonracemic diarylmethanols were obtained in high yields and enantioselectivities. [source] Palladium-Catalyzed C2 or C5 Direct Arylation of 3-Formylthiophene Derivatives with Aryl BromidesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 4 2010Jia Jia Dong Abstract The system Pd(OAc)2/dppb was found to be an efficient catalyst precursor for the direct arylation of 3-formylthiophene derivatives. When using 3-formylthiophene, the 2-arylated thiophenes were obtained with regioselectivities of 76,86,%, whereas the arylation of 3-formylthiophene diethyl acetal gave the 5-arylated thiophenes with regioselectivities of 64,88,%. These reactions were performed by using only 0.1 mol-% of the catalyst. Moreover, this procedure has been found to be tolerant to a variety of functional groups on the aryl bromide such as formyl, propionyl, benzoyl, nitrile, or nitro. [source] Selective Palladium-Catalysed ipso Arylation of ,,,-Disubstituted Benzo[b]thien-2-ylmethanols with Aryl Bromides using PCy3 as LigandEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2007A. Beatrix Bíró Abstract ,,,-Diphenylbenzo[b]thien-2-ylmethanol was treated with a series of aryl bromides in the presence of palladium(II) acetate and tricyclohexylphosphane to give the appropriate 2-aryl-benzo[b]thiophenes in good to excellent yield with concomitant formation of benzophenone. The reaction wassuccessfully extended to ,,,-diphenylbenzo[b]thien-3-ylmethanol, although in certain cases the transformation was biased by concurrent ortho arylation. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Direct Synthesis of Protected Arylacetaldehydes by Tetrakis(phosphane)palladium-Catalyzed Arylation of Ethyleneglycol Vinyl EtherEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2006Isabelle Kondolff Abstract A range of aryl bromides undergo Heck reaction with ethylene glycol vinyl ether, in the presence of [PdCl(C3H5)]2/cis,cis,cis -1,2,3,4-tetrakis[(diphenylphosphanyl)methyl]cyclopentane as catalyst, to give regioselectively protected arylacetaldehydes in good yields. The ,-arylation products were obtained in with 93,100,% selectivity with electron-poor aryl bromides or heteroaryl bromides. Furthermore, this catalyst can be used at low loading, even for reactions with sterically hindered aryl bromides. The aryl vinyl ether intermediates undergo subsequent ketalisation to give the corresponding 2-benzyl-1,3-dioxolane derivatives.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] An Efficient N -Arylation of Heterocycles with Aryl-, Heteroaryl-, and Vinylboronic Acids Catalyzed by Copper FluorapatiteHELVETICA CHIMICA ACTA, Issue 5 2010Lakshmi Kantam, Mannepalli Abstract N -Arylation of N-containing heterocycles, such as pyrazoles, imidazoles, and benzimidazoles with aryl-, heteroaryl-, and vinylboronic acids was efficiently carried out by copper fluorapatite (CuFAP) catalyst in MeOH at room temperature under base-free conditions. The N- arylated heterocycles were isolated in good-to-excellent yields. [source] Evaluation of Electron-Deficient Phosphine Ligands for Direct Arylation of HeterocyclesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Olivier René Abstract New electron-deficient biarylphosphine ligands were studied and proved to be efficient for the direct arylation of heteroarenes with aryl iodides. The ability of a more electron-deficient palladium centre to accelerate the arylation of heterocycles that remained unreactive with aryl iodides in the past has been validated and these heteroarenes can now be smoothly reacted in the presence of a new electrophilic catalyst. Experimental evidence suggests a viable concerted metalation,deprotonation pathway for the CH bond cleavage step with an electron-deficient palladium centre. [source] (,6 -Arene)ruthenium(N-heterocyclic carbene) Complexes for the Chelation-Assisted Arylation and Deuteration of Arylpyridines: Catalytic Studies and Mechanistic InsightsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7 2010Amparo Prades Abstract A series of (,6 -arene)ruthenium complexes have been tested in the arylation of arylpyridines. One (,6 - p -cymene)ruthenium(N-heterocyclic carbene) complex (labelled as 1 in the text) was found to be the most effective, being capable of arylating a wide set of substantially different arylpyridines. Complex 1 is also able to promote the regioselective deuteration of a series of arylated N-heterocycles, via a nitrogen-directed mechanism. Two of the deuterated amines were used to measure the kinetic isotope effect (KIE) in the arylation process. The detection of an inverse KIE, together with the observation that the CH activation process does not require the addition of a base, suggest that the rate-limiting step in the arylation process may be different to that of previously reported studies. [source] Highly Efficient Ligands for the Palladium-Assisted Double N -Arylation of Primary Amines for One-Sep Construction of CarbazolesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010Yibo Zhou Abstract A highly efficient one-pot synthesis of carbazoles via palladium-catalyzed double N -arylation of primary amines with 2,2,-dihalobiphenyls is described using a catalyst system comprised of tris(dibenzylideneacetone)dipalladium(0) (Pd2dba3) and the proazaphosphatrane P(i -BuNCH2CH2)3N (8) or its derivative (t- Bu)2PNP(i- BuNCH2CH2)3N (9a) as the ligand. The process is effective for double N -arylation of 2,2,-biphenyl dibromide, diiodide, and even dichloride with a variety of primary amines including neutral, electron-rich, electron-deficient, and sterically hindered anilines as well as aliphatic amines. [source] Palladium-Catalysed Direct Arylation of Heteroaromatics Bearing Unprotected Hydroxyalkyl Functions using Aryl BromidesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010Julien Roger Abstract Heteroaromatics bearing unprotected hydroxyalkyl functions can be arylated using aryl or heteroaryl bromides, via palladium-catalysed carbon-hydrogen bond activation/arylation. Good yields were generally obtained using 0.01,0.5,mol% of the air-stable palladium acetate complex as the catalyst. The nature of the base was found to be crucial for the selectivity of this reaction. Potassium acetate led to the direct arylation products whereas caesium carbonate led to the formation of the ether. This procedure is certainly more atom-economic than other methods for the preparation of such compounds, as no protection/deprotection sequence of the hydroxyalkyl function and no preparation of an organometallic derivative is required. [source] Highly Efficient Copper-Catalyzed Synthesis of Internal Alkynes via Aerobic Oxidative Arylation of Terminal AlkynesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Honghua Rao Abstract We have developed a novel and highly efficient, copper-catalyzed synthesis of internal alkynes via oxidative couplings of aromatic boronic acids with terminal alkynes at room temperature. The protocol uses inexpensive copper(I) oxide [Cu2O] as the catalyst, oxygen in the air as the stoichiometric oxidant; no ligand and sealed reaction vessels are required, and remarkable functional group tolerability is observed with coupling occurring. [source] Synthesis of 2,3-Diarylbenzo[b]thiophenes via Nickel-Catalyzed Suzuki,Miyaura Cross-Coupling and Palladium-Catalyzed Decarboxylative ArylationADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 16 2009Mitsuru Miyasaka Abstract We report a new approach to 2,3-diarylbenzo[b]thiophenes based on the nickel-catalyzed Suzuki,Miyaura cross-coupling/palladium-catalyzed decarboxylative arylation sequence of 3-chloro-2-methoxycarbonylbenzo[b]thiophenes, which are readily accessible from the corresponding cinnamic acids. In addition, this methodology can be applied to the concise synthesis of ,-extended 2,3,6,7-tetraarylbenzo[1,2- b;4,5- b,]dithiophenes. Their optical properties are also described. [source] Regioselective C-2 or C-5 Direct Arylation of Pyrroles with Aryl Bromides using a Ligand-Free Palladium CatalystADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Julien Roger Abstract A simple and atom-economical procedure for the regioselective C-2 or C-5 arylation of pyrroles via a CH bond activation is reported. Only 0.5,0.01 mol% of commercially available and air-stable ligand-free palladium(II) acetate [Pd(OAc)2] was employed as the catalyst. The presence of electron-withdrawing substituents such as formyl, acetyl or ester at the C-2 position of the pyrrole is tolerated. This environmentally attractive procedure has also been found to be tolerant to a very wide variety of functional groups on the aryl bromides such as formyl, acetyl, propionyl, ester, nitrile, nitro, fluoro, methoxy, amino or trifluoromethyl. [source] Copper-Catalyzed N -Arylation of Hindered Substrates Under Mild ConditionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2009Michael Abstract A mild, efficient method utilizing a copper-diamine catalyst at room temperature is reported for the coupling of hindered imidazoles with unsubstituted, ortho- substituted, and bis- ortho -substituted boronic acids in good to excellent yields. Aryl halides do not reaction under these conditions permitting sequential N -arylation reactions. [source] Palladium-Catalyzed Direct C-4 Arylation of 2,5-Disubstituted Furans with Aryl BromidesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2008Aditya Abstract A simple and atom-economic procedure for the selective C-4 arylation of 2,5-disubstituted furans via CH bond activation using electron-deficient aryl bromides is reported. Only 0.5 mol% of the commercially available dimeric (allene)palladium chloride, [Pd(C3H5)Cl]2, was employed as catalyst. This environmentally attractive procedure has been found to be tolerant to a variety of functional groups on the aryl bromide such as carbonyl, nitrile, nitro, fluoro, ester or trifluoromethyl. [source] Highly Practical "Ligand-Free-Like" Copper-Catalyzed N -Arylation of Azoles in Lower Nitrile SolventsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2008Rui Zhu Abstract In lower nitrile solvents, the N -arylation of azoles with aryl halides was achieved efficiently in the presence of copper powder without any additional ligands. Thus, the first nitrile type of monodentate ligand-mediated, "ligand-free-like" copper-catalyzed N -arylation procedure was established. [source] Simple Methodology for Heck Arylation at C-8 of Adenine NucleosidesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2008Pallavi Lagisetty Abstract A simple method for the arylation of 8-vinyladenine nucleoside derivatives is reported. With a broad set of aryl iodides and bromides, the reaction is catalyzed by the simple combination palladium acetate/tris(o -tolyl)phosphine/triethylamine [Pd(OAc)2/(o -tol)3P/Et3N]. As expected, aryl chlorides are more difficult coupling partners but some undergo reactions with more exotic catalysts. Although trans -olefins are the major products, minor amounts of cis -isomers are detected in some cases, and a post -arylation mechanism for their formation is proposed. Finally, by subtle catalyst modulation chemoselective N -arylation of the nucleoside can be achieved in the presence of the vinyl moiety. [source] Ligand-Free Copper-Catalyzed N -Arylation of Nitrogen NucleophilesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17-18 2007Arkaitz Correa Abstract Versatile, simple and inexpensive ligand-free, copper-catalyzed N -arylations of sulfoximines and nitrogen-containing heterocycles have been developed affording N -arylated products in high yields. [source] Palladium-Catalyzed N -Arylation of N,N -Dialkylhydrazines with Aryl ChloridesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2007Sandro Cacchi Abstract N,N -Dialkyl- N, -arylhydrazines have been prepared usually in high to excellent yields via the reaction of N,N -dialkylhydrazines with aryl chlorides in the presence of Pd2(dba)3, Xphos and NaO- t- Bu in dioxane at 120,°C. With ortho -substituted aryl chlorides best results have been obtained by using 2-(2,,6,-dimethoxybiphenyl)dicyclohexylphosphine (ligand d) as the ligand. [source] An Inexpensive and Efficient Copper Catalyst for N -Arylation of Amines, Amides and Nitrogen-Containing HeterocyclesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 15 2006Xun Guo Abstract An inexpensive and efficient catalyst system has been developed for the N -arylation of nitrogen-containing compounds including a variety of amines, amides, indole and imidazole. This simple protocol uses CuI as the catalyst, commercial available pipecolinic acid as the new ligand, K2CO3 as the base and DMF as the solvent. [source] N -Arylation of N-H heterocycles with aryl bromides and aryl iodides using cui and kf/Al2O3JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2008Rahman Hosseinzadeh Copper-catalyzed system for N -arylation of N-H group in heterocycles such as indole, pyrrole and carbazole with aryl iodides and aryl bromides using potassium fluoride supported on alumina as a base is described. This is a simple and efficient method for the coupling of aryl iodides and bromides with N-H heterocycles. Different functionalized iodo and bromo arenes were coupled with N-H heterocycles using this system. [source] Berichtigung: Palladium-Catalyzed ,-Arylation of ,,,-Unsaturated Esters from Silyl Ketene AcetalsANGEWANDTE CHEMIE, Issue 40 2010David No abstract is available for this article. [source] Palladium-Catalyzed ,,Arylation of Carboxylic Esters,ANGEWANDTE CHEMIE, Issue 40 2010Alice Renaudat Alter ego: In Gegenwart eines geeigneten Palladium(0)-Katalysators reagierten Carbonsäureester mit Arylhalogeniden mit elektronegativem ortho -Substituenten in einer ,-Arylierung anstelle der häufigeren ,-Arylierung (siehe Schema; Cy=Cyclohexyl). Eine asymmetrische Version der Reaktion lieferte das Produkt mit einem Enantiomerenverhältnis von bis zu 77:23. [source] A Versatile Palladium/Triphosphane System for Direct Arylation of Heteroarenes with Chloroarenes at Low Catalyst Loading,ANGEWANDTE CHEMIE, Issue 37 2010David Roy Ein luftbeständiger Palladiumkatalysator mit dreizähnigem Phosphanligand aryliert elektronenreiche wie elektronenarme mehrfach substituierte Furane (X=O), Thiophene (X=S) und Pyrrole (X=NR5) sowie Thiazole direkt unter C-H-Aktivierung mit Chlorarenen (siehe Schema; DMAc=N,N -Dimethylacetamid, TBAB=Tetra- n -butylammoniumbromid). [source] Zurückziehung: Facile Palladium-Catalyzed Arylation of Heterocycles and Nonactivated Arenes with Aryl ChloridesANGEWANDTE CHEMIE, Issue 35 2010Jan Pschierer No abstract is available for this article. [source] Zurückziehung: Facile Palladium-Catalyzed Arylation of Heterocycles and Nonactivated Arenes with Aryl Chlorides,ANGEWANDTE CHEMIE, Issue 35 2010Jan Pschierer [source] Palladium-Catalyzed ,-Arylation of ,,,-Unsaturated Esters from Silyl Ketene Acetals,ANGEWANDTE CHEMIE, Issue 33 2010David Smarter Katalysator: Eine Methode für die Palladium-katalysierte ,-Arylierung von ,,,-ungesättigten Estern wurde entwickelt, die über Silylketenacetale verläuft und ohne Fluorid-Aktivatoren auskommt. Die Kupplung gelingt mit elektronenreichen und elektronenarmen Aryl- und Vinylbromiden in hohen Ausbeuten, und andere funktionelle Gruppen werden gut toleriert. [source] A P,N-Ligand for Palladium-Catalyzed Ammonia Arylation: Coupling of Deactivated Aryl Chlorides, Chemoselective Arylations, and Room Temperature Reactions,ANGEWANDTE CHEMIE, Issue 24 2010Rylan Von Ammoniak zu Arylaminen: Der neue luftbeständige P,N-Ligand Mor-DalPhos ermöglicht palladiumkatalysierte Kreuzkupplungen von Ammoniak mit verschiedenartigen Arylchloriden und -tosylaten. Die Reaktionen laufen hoch chemoselektiv und erstmals auch schon bei Raumtemperatur ab (siehe Schema; Ad=Adamantyl). [source] Iron-Catalyzed Direct Arylation of Unactivated Arenes with Aryl Halides,ANGEWANDTE CHEMIE, Issue 11 2010Wei Liu Eiserne Hilfe: Eine Vielzahl an Arylhalogeniden wurde mit nichtaktivierten Arenen in mäßigen bis guten Ausbeuten zu Biarylverbindungen umgesetzt. Die Reaktionen wurden bei relativ niedriger Temperatur in Gegenwart katalytischer Mengen FeCl3 mit DMEDA als Ligand und LiHMDS als Base durchgeführt (siehe Schema; DMEDA=N,N' -Dimethylethan-1,2-diamin, HDMS=Hexamethyldisilazanid). [source] | |||||||||||||||||||||||||