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Aryl Alkyl Ketones (aryl + alkyl_ketone)
Selected AbstractsRuthenium-Catalyzed Enantioselective Reduction of Electron-Rich Aryl Alkyl Ketones.CHEMINFORM, Issue 49 2006Jenny Wettergren 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] (E)-Selective Horner,Wadsworth,Emmons Reaction of Aryl Alkyl Ketones with Bis(2,2,2-trifluoroethyl)phosphonacetic Acid.CHEMINFORM, Issue 10 2004Shigeki Sano Abstract For Abstract see ChemInform Abstract in Full Text. [source] Convenient Enantioselective Hydrosilylation of Ketones Catalyzed by Zinc-Macrocyclic Oligoamine ComplexesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2009Jadwiga Gajewy Abstract Chiral macrocyclic tetra- and hexamine macrocycles derived from trans -1,2-diaminocyclohexane (DACH) in complexes with diethylzinc efficiently catalyze the asymmetric hydrosilylation of aryl alkyl ketones with enantiomeric excess of the product up to 89%. The cyclic structure of the trianglamine ligand increases the enantioselectivity of the reaction, in comparison to the catalysis with the acyclic N,N, -dibenzyl-DACH ligand. Density functional theory (DFT) computations on the structures of ligand-zinc complexes and on the structures of these complexes with a coordinated acetophenone molecule allow us to rationalize the direction of the asymmetric induction of the hydrosilylation reaction as well as the superiority of the cyclic ligand compared to the acyclic one. This is the first example of asymmetric catalysis for the hydrosilylation reaction of ketones with the use of a readily available, inexpensive, and reusable macrocyclic trianglamine ligand. [source] Discrete versus In Situ -Generated Aluminum-Salen Catalysts in Enantioselective Cyanosilylation of Ketones: Role of Achiral LigandsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 5 2008Ali Alaaeddine Abstract The monometallic species {Salen}AlX (X=Me, 2a,b; X=Cl, 4a,b; O- i- Pr, 5a,b) and open bimetallic species {Salen}[AlMe2]2 (3a,b) that result from binary combinations between an aluminum precursor [trimethylaluminum, dimethylaluminum chloride, aluminum tris(isopropoxide)] and a diprotio {Salen}H2 pro-ligand 1a,b (a=1R,2R -cyclohexyl-salen; b=1R,2R -diphenylethylene-salen) have been isolated. The crystal structures of 3b, 4b and of ,-oxo species [{diphenylethylene-salen}Al]2O (6b) are reported. The discrete species 2,5a,b have been individually evaluated in the asymmetric cyanosilylation of acetophenone. It is shown that, in several cases, these discrete catalysts display dramatically different performances than the catalyst systems in situ -generated from the binary combinations. The influence of the achiral ligand X on both the enantioselectivity and activity of the cyanosilylation reaction has been investigated, resulting in the definition of a highly active and productive hexafluoro-2-propoxide-based catalyst for a variety of aryl alkyl ketones (TON up to 470, TOF up to 140,h,1 at ,20,°C for acetophenone). [source] Investigations into the C -deuteriation of silyl enol ethers derived from aryl alkyl ketonesJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 9 2006Svitlana Buksha Abstract Results are reported on the regioselective C -deuteriation of a series of silyl enol ethers derived from aryl alkyl ketones using deuterium (D2) gas as the deuterium source and palladium-on-barium sulfate as the mediator. These results highlight the numerous reaction pathways and different product types available from simple deuteriation of substituted enol precursors. Copyright © 2006 John Wiley & Sons, Ltd. [source] Highly Enantioselective Ruthenium-Catalyzed Reduction of Ketones Employing Readily Available Peptide LigandsCHEMISTRY - A EUROPEAN JOURNAL, Issue 1 2004Anders Bøgevig Dr. Abstract Highly efficient and selective catalysts for the asymmetric reduction of aryl alkyl ketones under hydrogen-transfer conditions (2-propanol) were obtained by combining a novel class of pseudo-dipeptide ligands with [{RuCl2(p- cymene)}2]. A library of 36 dipeptide-like ligands was prepared from N -Boc-protected ,-amino acids and the enantiomers of 2-amino-1-phenylethanol and 1-amino-2-propanol. The catalyst library was evaluated with the reduction of acetophenone and excellent enantioselectivity of 1-phenylethanol was obtained with several of the novel catalysts. A ligand based on the combination of N -Boc- L -alanine and (S)-1-amino-2-propanol (ligand A - (S)- 4) was found to be particular effective. When the situ formed ruthenium complex of this ligand was employed as the catalyst in the hydrogen-transfer reaction of various aryl alkyl ketones, the corresponding alcohol products were achieved in excellent enantioselectivity (up to 98,% ee). [source] | ||||||||||