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Carbene Precursors (carbene + precursor)
Selected AbstractsImidazol(in)ium-2-carboxylates as N-Heterocyclic Carbene Precursors for the Synthesis of Second Generation Ruthenium Metathesis CatalystsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009Xavier Sauvage Abstract Five well-known ruthenium-N-heterocyclic carbene (NHC) catalysts for olefin metathesis and related reactions, including the second generation Grubbs and Hoveyda,Grubbs catalysts, were prepared by phosphane exchange between first generation ruthenium-benzylidene or indenylidene complexes and NHCs generated in situ upon thermolysis of imidazol(in)ium-2-carboxylates. Because N-heterocyclic carbene carbon dioxide adducts (NHC,CO2) are stable zwitterionic compounds that can be stored and handled with no particular precautions, this procedure is particularly attractive from a practical point of view. Reaction courses were conveniently monitored by 31P,NMR spectroscopy and the experimental conditions were carefully adjusted to obtain high yields of pure products within short periods of time. [source] ChemInform Abstract: The Synthesis of Some Benzimidazolium Salts and Use as Carbene Precursors in the Heck and Suzuki Reactions.CHEMINFORM, Issue 35 2010Beyhan Yigit Abstract 1-(2-Diisopropylaminoethyl)-3-alkylbenzimidazolium salts are shown to be good catalysts for Heck and Suzuki reactions. [source] ChemInform Abstract: Catalytic Reactions of Carbene Precursors on Bulk Gold Metal.CHEMINFORM, Issue 1 2010Yibo Zhou Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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] An Efficient and Versatile Approach for the Immobilization of Carbene Precursors via Copper-Catalyzed [3 + 2]-Cycloaddition and Their Catalytic Application.CHEMINFORM, Issue 51 2007Kirsten Zeitler 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] Microwave-Assisted Synthesis of N-Heterocyclic Carbene Precursors.CHEMINFORM, Issue 24 2006Adila Aidouni 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] Supramolecular encapsulation of 1,3-bis(1-adamantyl)imidazolium chloride by ,-cyclodextrins: towards inhibition of C(2)-H/D exchangeJOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 2 2009Loïc Leclercq Abstract The study of the hydrogen/deuterium exchange reactions of the C(2)-proton for different carbene precursors has been carried out in the absence and presence of ,-cyclodextrin in D2O at 25°C. Formation of the inclusion complexes of imidazolium salts with the native ,-cyclodextrin and the ,-dimethylcyclodextrin is demonstrated by 1D and 2D 1H NMR, ESI/HRMS and a molecular modelling study. Formation of the inclusion complexes of imidazolium salts with the native ,-cyclodextrin and the ,-dimethylcyclodextrin is a simple and efficient method to modify the acidity of the imidazolium H(2) and to modify its environment. Encapsulation of 1,3-disubstituted imidazolium chloride by ,-cyclodextrins results in the inhibition of the H(2)/D exchange in the complex. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||