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Palladium-Catalyzed Reaction (palladium-catalyzed + reaction)
Selected AbstractsPalladium-Catalyzed Reaction of o-Alkynyltrifluoroacetanilides with 1-Bromoalkynes.CHEMINFORM, Issue 51 20052-Substituted 3-Acylindoles., An Approach to 2-Substituted 3-Alkynylindoles No abstract is available for this article. [source] Palladium-Catalyzed Reaction of 2-Hydroxy-2-methylpropiophenone with Aryl Bromides: A Unique Multiple Arylation via Successive C,C and C,H Bond Cleavages.CHEMINFORM, Issue 44 2004Hiroyuki Wakui No abstract is available for this article. [source] Palladium-Catalyzed Reaction of Aryl Iodides with Acetic Anhydride.CHEMINFORM, Issue 24 2003A Carbon Monoxide Free Synthesis of Acetophenones. Abstract For Abstract see ChemInform Abstract in Full Text. [source] Palladium-Catalyzed Reaction of Acylzirconocene Chloride and Stereoselective Formation of Bicyclo[3.3.0] Compounds.CHEMINFORM, Issue 13 2003Yuji Hanzawa Abstract For Abstract see ChemInform Abstract in Full Text. [source] Palladium-Catalyzed Reactions of Vinylidenecyclopropanes with Acetic Acid.CHEMINFORM, Issue 1 2007Jian-Mei Lu 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] Chemoselective Palladium-Catalyzed Reaction in Aqueous Media: Selectivity in the Reaction of Haloanilines with 1,1-Dimethylallyl AlcoholADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4-5 2007Yuusaku Yokoyama Abstract Palladium-catalyzed reactions of various haloanilines with 1,1-dimethylallyl alcohol were carried out in the presence of a hydrophilic ligand, 3,3,,3,,-phosphinidyne tris(benzenesulfonic acid) trisodium salt (TPPTS), or a lipophilic phosphine ligand, 1,1,-bis(diphenylphosphino)ferrocene (DPPF). The reactions proceeded chemoselectively in aqueous solvent to give C -vinylated products under basic conditions or N -allylated products under neutral conditions in practical yields (up to 79,%). The use of an aqueous solvent played an important role in this chemoselectivity and allowed the development of a one-pot synthesis of 3-methylindole. This chemoselectivity is synthetically useful because the reactive position of haloanilines can be controlled simply by changing the basicity of the reaction medium, which eliminates the need to protect the amino group during the reaction. [source] Regioselective Carbon,Carbon Bond Formation in Proteins with Palladium Catalysis; New Protein Chemistry by Organometallic ChemistryCHEMBIOCHEM, Issue 1 2006Koichiro Kodama Abstract Palladium-catalyzed reactions have contributed to the advancement of many areas of organic chemistry, in particular, the synthesis of organic compounds such as natural products and polymeric materials. In this study, we have used a Mizoroki,Heck reaction for site-specific carbon,carbon bond formation in the Ras protein. This was performed by the following two steps: 1) the His6 -fused Ras protein containing 4-iodo- L -phenylalanine at position 32 (iF32-Ras-His) was prepared by genetic engineering and 2) the aryl iodide group on the iF32-Ras-His was coupled with vinylated biotin in the presence of a palladium catalyst. The biotinylation was confirmed by Western blotting and liquid chromatography,mass spectrometry (LC-MS). The regioselectivity of the Mizoroki,Heck reaction was furthermore confirmed by LC-MS/MS analysis. However, in addition to the biotinylated product (bF32-Ras-His), a dehalogenated product (F32-Ras-His) was detected by LC-MS/MS. This dehalogenation resulted from the undesired termination of the Mizoroki,Heck reaction due to steric and electrostatic hindrance around residue 32. The biotinylated Ras showed binding activity for the Ras-binding domain as its downstream target, Raf-1, with no sign of decomposition. This study is the first report of an application of organometallic chemistry in protein chemistry. [source] Total Synthesis without Protection: Three-Step Synthesis of Optically Active Clavicipitic Acids by a Biomimetic RouteEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2004Yuusaku Yokoyama Abstract A three-step synthesis of a mixture of optically active cis - and trans -clavicipitic acids 6, which are ergot alkaloids, was achieved, starting from 4-bromoindole (7) and dl -serine (dl - 2). This short synthesis was made possible by omitting the protection and deprotection steps from the synthetic route. The key step was the spontaneous cyclization of 4-vinyltryptophan (10) formed from the Heck reaction of 4-bromotryptophan (8) with 2-methyl-3-buten-2-ol (9) in aqueous media. During this investigation, we also found that the palladium-catalyzed reaction of 8 with 9 showed an interesting pH dependence; under strongly basic conditions, the Heck reaction occurred to give a C4 -vinylated product 10, whereas an N -allylated product 19b was formed under neutral or weakly basic conditions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Unexpected regioselectivity in the palladium-catalyzed reaction of silacyclobutanes with aryl iodidesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 8 2001Yoshifumi Tanaka Abstract The reaction of aryl iodides with 1,1-diphenyl-silacyclobutane in the presence of a catalytic amount of Pd(PPh3)4 affords unexpected ring-opening adducts, 1- and 2-propenyl(triaryl)-silanes, in good yields. On the other hand, the PdCl2(PhCN)2 -catalyzed reaction of 1,1-diphenylsilacyclobutanes with aryl halides gives unexpected products, triarylsilanols, after hydrolysis in moderate yields. The catalysis involves the reaction of aryl,palladium intermediates with silacyclobutanes along with regioselective aryl,silicon bond formation. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||