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Catalytic Transfer Hydrogenation (catalytic + transfer_hydrogenation)
Selected Abstracts16-Electron (Arene)ruthenium Complexes with Superbasic Bis(imidazolin-2-imine) Ligands and Their Use in Catalytic Transfer HydrogenationEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 29-30 2009Thomas Glöge Abstract The ligands N,N, -bis(1,3,4,5-tetramethylimidazolin-2-ylidene)-1,2-ethanediamine (BLMe) and N,N, -bis(1,3-diisopropyl-4,5-dimethylimidazolin-2-ylidene)-1,2-ethanediamine(BLiPr) react with [(,5 -C5Me5)RuCl]4 to afford cationic 16-electron half-sandwich complexes [(,5 -C5Me5)Ru(BLR)]+ (R = Me, 3; R = iPr, 4), which resist coordination of the chloride counterion because of the strong electron-donating ability of the diimine ligands. Upon reaction with [(,6 -C6H6)RuCl2]2 or [(,6 -C10H14)RuCl2]2, these ligands stabilize dicationic 16-electron benzene and cymene complexes of the type [(,6 -C6H6)Ru(BLR)]2+ (R = Me, 5; R = iPr, 6) and [(,6 -C10H14)Ru(BLR)]2+ (R = Me, 7; R = iPr, 8). The X-ray crystal structure of [5]Cl2 reveals the absence of any direct Ru,Cl interaction, whereas a long Ru,Cl bond, supported by two CH···Cl hydrogen bonds, is observed for [(6)Cl]Cl in the solid state. Treatment of the dichlorides of 6 and 8 with NaBF4 affords [6](BF4)2 and [8](BF4)2, which are composed of individual dications and tetrafluoroborate ions with no direct Ru,F interaction. All complexes catalyze the transfer hydrogenation of acetophenone in boiling 2-propanol. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Heterogeneous Catalytic Transfer Hydrogenation of Aromatic Nitro and Carbonyl Compounds over Cobalt(II) Substituted Hexagonal Mesoporous Aluminophosphate Molecular Sieves.CHEMINFORM, Issue 6 2003Susanta K. Mohapatra Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Catalytic Transfer Hydrogenation of Aromatic Nitro Compounds by Employing Ammonium Formate and 5% Platinum on Carbon.CHEMINFORM, Issue 1 2001D. Channe Gowda 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] Synthesis of 3,7,8- 15N3 -N1 -(, -D- erythro -pentofuranosyl)-5-guanidinohydantoinJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 14 2003Hongbin Yu Abstract 3,7,8- 15N3 -N1 -(, -D- erythro -pentofuranosyl)-5-guanidinohydantoin was synthesized from the oxidation of 1,7,NH2 - 15N3 -8-oxo-7,8-dihydro-2,-deoxyguanosine with 2 equivalents of Ir(IV) in pH 4.5 potassium phosphate buffer. The synthesis of 1,7,NH2 - 15N3 -8-oxo-7,8-dihydro-2,-deoxyguanosine started with bromination of 1,7,NH2 - 15N3 -2,-deoxyguanosine. The resulting 1,7,NH2 - 15N3 -8-bromo-7,8-dihydro-2,-deoxyguanosine reacted with sodium benzyloxide to afford 1,7,NH2 - 15N3 -8-benzyloxy-7,8-dihydro-2,-deoxyguanosine. Subsequent catalytic transfer hydrogenation of 1,7,NH2 - 15N3 -8-benzyloxy-7,8-dihydro-2,-deoxyguanosine with cyclohexene and 10% Pd/C yielded 1,7,NH2 - 15N3 -8-oxo-7,8-dihydro-2,-deoxyguanosine. Purification of 3,7,8- 15N3 -N1 -(, -D- erythro -pentofuranosyl)-5-guanidinohydantoin was first carried out on a C18 column and the product was further purified on a graphite column. ESI-MS was used to confirm the identity and to determine the isotopic purity of all the labeled compounds. The isotopic purity of 3,7,8- 15N3 -N1 -(, -D- erythro -pentofuranosyl)-5-guanidinohydantoin was 99.4 atom% based on LC-MS measurements. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||