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Heteroaryl Bromides (heteroaryl + bromide)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

ChemInform Abstract: (t-Bu)2PN=P(i-BuNCH2CH2)3N: New Efficient Ligand for Palladium-Catalyzed C,N Couplings of Aryl and Heteroaryl Bromides and Chlorides and for Vinyl Bromides at Room Temperature.

CHEMINFORM, Issue 35 2008
Ch. Venkat Reddy
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Highly Efficient and Practical Phosphoramidite,Copper Catalysts for Amination of Aryl Iodides and Heteroaryl Bromides with Alkylamines and N(H)-Heterocycles.

CHEMINFORM, Issue 34 2006
Zhanjin Zhang
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

Palladium-Catalysed Direct C-H Activation/Arylation of Heteroaromatics: An Environmentally Attractive Access to Bi- or Polydentate Ligands

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 16 2008
Fazia Derridj
Abstract Bi- or polydentate ligands based on heterocycles can be easily prepared by palladium-catalysed C,H bond activation of heteroaromatics followed by heteroarylation with heteroaryl bromides. A variety of heteroaromatics such as furans, thiophenes, pyridines, thiazoles or oxazole derivatives have been employed and moderate to good yields were generally obtained using the air-stable complex [PdCl(dppb)(C3H5)] as catalyst. A range of functions such as acetyl, formyl, ester or nitrile on the heteroaromatics is tolerated.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]

Very Fast Suzuki,Miyaura Reaction Catalyzed by Pd(OAc)2 under Aerobic Conditions at Room Temperature in EGME/H2O

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2009
Alessandro Del Zotto
Abstract The results of a ligand-free Pd(OAc)2 -catalyzed Suzuki,Miyaura C,C coupling performed at room temperature under aerobic conditions are presented. It was found that the use of an ethylene glycol monomethyl ether/H2O mixture as the solvent resulted in very rapid reactions of aryl bromides with arylboronic acids. As a matter of fact, under optimized conditions, some substrates were converted quantitatively in less than 1 min with exceptionally high TOF values. For example, the reaction between 4-methoxyphenylboronic acid and bromobenzene afforded 4-methoxybiphenyl in 30 s with TOF = 180000 h,1. Furthermore, the reaction tolerates a wide range of functional groups and can be successfully applied to heteroaryl bromides such as 2-bromopyridine and 5-bromopyrimidine. Interestingly, also an activated aryl chloride such as 1-chloro-4-nitrobenzene reacted quantitatively with phenylboronic acid at 373 K. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

Direct Synthesis of Protected Arylacetaldehydes by Tetrakis(phosphane)palladium-Catalyzed Arylation of Ethyleneglycol Vinyl Ether

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 3 2006
Isabelle 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]

Cyclopalladated Ferrocenylimine as Efficient Catalyst for the Syntheses of Arylboronate Esters

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2010
Lianhui Wang
Abstract The cyclopalladated ferrocenylimine I and its phosphine adducts IIa,f were prepared and evaluated in the borylation of aryl halides. The tricyclohexylphosphine adduct IIb exhibited highly catalytic activity for the coupling of aryl and heteroaryl bromides containing various functional groups with low catalyst loading (2,mol%). Aryl and heteroaryl chlorides were smoothly converted into the corresponding boronates in the presence of the monophosphinobiaryl ligand (XPhos) adduct IIf. It was proposed that palladacycle was only a reservoir of the catalytically active species from the investigation on the reaction mechanism. [source]

Palladium-Catalysed Direct Arylation of Heteroaromatics Bearing Unprotected Hydroxyalkyl Functions using Aryl Bromides

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010
Julien 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]