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Simple Ketones (simple + ketone)
Selected AbstractsDDQ-Mediated Direct Cross-Dehydrogenative-Coupling (CDC) Between Benzyl Ethers and Simple Ketones.CHEMINFORM, Issue 32 2006Yuhua 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] A Modular Design of Ruthenium Catalysts with Diamine and BINOL-Derived Phosphinite Ligands that Are Enantiomerically-Matched for the Effective Asymmetric Transfer Hydrogenation of Simple Ketones.CHEMINFORM, Issue 43 2005Rongwei Guo Abstract For Abstract see ChemInform Abstract in Full Text. [source] Ruthenium-catalyzed carbonylative cycloaddition reactions involving carbonyl and imino groups as assembling unitsTHE CHEMICAL RECORD, Issue 4 2008Naoto Chatani Abstract This paper describes carbonylative cycloaddition reactions catalyzed by Ru3(CO)12. Ru3(CO)12 was found to catalyze an intramolecular Pauson,Khand-type reaction. Carbonylative cycloaddition reactions involving a carbonyl group in aldehydes, ketones, and esters as a two-atom assembling unit were also achieved in the presence of Ru3(CO)12 as the catalyst. The reaction of 5-hexyn-1-al and 6-heptyn-1-al derivatives with CO in the presence of Ru3(CO)12 resulted in cyclocarbonylation from which bicyclic ,, ,-unsaturated lactones were obtained. Intermolecular [2,+,2,+,1] carbonylative cycloaddition of alkenes, ketones, and CO was also catalyzed by Ru3(CO)12 as the catalyst to give saturated ,-lactone derivatives. Simple ketones were not applicable, but ketones having a CO or CN group at the ,-position served as a good substrate. These reactions could be extended to carbonylative cycloaddition of the corresponding imines leading to ,-butyrolactam derivatives. The [4,+,1] carbonylative addition of ,,,-unsaturated imines leading to unsaturated ,-lactams was achieved with Ru3(CO)12. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 201,212; 2008: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.20149 [source] Thioenols and thioamides substituted by two , -EWGs.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 6 2008Comparison with analogous amides, enols Abstract Condensation of organic isothiocyanates with active methylene compounds gave nine thioamides RNHCSCHYY, or their isomeric thioenols RNHC(SH),=,CYY, for substrates in which Y and Y, are electron-withdrawing groups (EWG). These included derivatives of Meldrum's acid (MA) which showed 100% thioenol in all solvents. For other compounds the percentages of thioenol in CDCl3 when R,=,Ph are 100% when Y,=,CN and Y,,=,CO2Me or Y,,=,CO2CH2CCl3, 6% when Y,=,Y,,=,CO2CH2CF3, and 0% when Y,=,Y,,=,CO2Me. The chemical shift of SH (highest values 12.0,16.0,ppm) served as a probe for the thioenol structures and also for the extent of hydrogen bonding to the SH group. In contrast to simple ketones and thioketones in which thioenolization is favored over enolization by factors as large as 106, for intramolecular competition KThioenol/KEnol ratios are much lower than for systems not substituted by , -EWGs. X-ray crystallography of the 5-anilido-MA derivative shows a hydrogen-bonded thioenol structure. ,(OH), ,(NH), KEnol, and crystallographic data for analogous thioenol and enol systems are compared. Copyright © 2008 John Wiley & Sons, Ltd. [source] Ru-catalyzed Asymmetric Hydrogenation of Aryl Ketones Using Tetrazole Derived NH2 -hybrid LigandCHINESE JOURNAL OF CHEMISTRY, Issue 12 2009Fusheng Bie Abstract Readily available chiral hybrid NH2/tetrazole ligand [(S)-TEA, 1] in combination with Ru-BINAP or Ru-DIOP complexes catalyzes the asymmetric hydrogenation of a number of simple ketones with moderate enantioselectivity (up to 72% ee). The tetrazole functionality results in reversal of the typically observed chiral-induction for related systems and allows for hydrogenation to be uncharacteristically conducted in (non-protic) THF solvent. The observed catalyst performance is sensitive to the reaction conditions employed and the particular compounds involved. The origins of such features are considered to derive from the added functionality provided by the tetrazole moiety in 1, which due to its modular nature provides a good basis for further development. [source] | ||||||||||