Asymmetric .ALPHA.-substituted phenethylamines. II. The enantioselective synthesis of 1-aryl-2-phenylethylamines from L- and D-amino acids by means of 1,3-asymmetric induction.
Synthesis of Air- and Moisture-Stable, Storable Chiral Oxorhenium Complexes and Their Application as Catalysts for the Enantioselective Imine Reduction
salicyloxazoline based oxorhenium(V) complexes have been synthesized and their catalytic application for the asymmetricreduction of ketimines using hydrosilane as hydride source is disclosed. A broad substrate scope, high yields, and excellent enantioselectivities (up to 99 %) are attained. Furthermore, the syntheses of enantiopure α‐amino esters, γ‐ and δ‐lactams, and isoindolinones have also been carried
合成了空气/水分稳定,晶体和可储存的手性水杨基恶唑啉基氧化(V)配合物,并公开了其在氢化硅烷作为氢化物源的情况下催化不对称还原酮亚胺的催化应用。获得了广泛的底物范围,高收率和出色的对映选择性(最高99%)。此外,对映体纯α-氨基酯,γ-和δ-内酰胺以及异吲哚啉酮的合成也已使用该方法进行。最后,该方法已应用于具有药物相关性的合成靶标,例如R -(+)-沙丁胺碱和R -(+)-crispine A.
Microwave-promoted synthesis of chiral pyridinium salts
作者:Gustavo H.R. Viana、Itamar C. Santos、Rosemeire B. Alves、Laurent Gil、Christian Marazano、Rossimiriam P.F. Gil
DOI:10.1016/j.tetlet.2005.09.036
日期:2005.11
The synthesis of several chiralpyridiniumsalts via Zincke’s reaction can be easily accomplished by domestic microwave oven irradiation. Yield enhancements, reduction of reaction time, and less racemization were observed under microwave heating when compared to conventional heating in similar conditions.
The synthesis of new oxazoline-containing bifunctional catalysts and their application in the addition of diethylzinc to aldehydes
作者:Vincent Coeffard、Helge Müller-Bunz、Patrick J. Guiry
DOI:10.1039/b822580j
日期:——
bifunctional catalysts is reported employing a microwave-assisted Buchwald–Hartwig aryl amination as the key step. Covalent attachment of 2-(o-aminophenyl)oxazolines and pyridine derivatives generated in good-to-high yields a series of ligands in two or three steps in which each part was altered independently to tune the activity and the selectivity of the corresponding catalysts. These catalysts prepared
The intermolecular diastereoselective and enantioselective synthesis of pyrrolo[1,2-a]indoles is developed through a [3+2] cycloaddition between silyl-indole derivatives and α,β-unsaturated N-acyl oxazolidinones by merging photocatalysis and Lewis acid catalysis.
吡咯并[1,2- a ]吲哚的分子间非对映选择性和对映选择性合成是通过甲硅烷基吲哚衍生物与α,β-不饱和N-酰基恶唑烷酮通过光催化和路易斯酸催化的[3 + 2]环加成反应而开发的。
Synthesis of New Chiral Aliphatic Amino Diselenides and Their Application as Catalysts for the Enantioselective Addition of Diethylzinc to Aldehydes
作者:Antonio L. Braga、Marcio W. Paixão、Diogo S. Lüdtke、Claudio C. Silveira、Oscar E. D. Rodrigues
DOI:10.1021/ol034773e
日期:2003.7.1
[reaction: see text] A set of chiral aliphatic amino diselenides have been synthesized from readily available starting materials in a straightforward synthetic route via the ring-opening reaction of the parent aziridines. These ligands have been tested as catalysts for the enantioselective addition of diethylzinc to aldehydes. The influence of the alkyl group substituents on the stereoselectivity has