Development of an<i>R</i>-Selective Amine Oxidase with Broad Substrate Specificity and High Enantioselectivity
作者:Rachel S. Heath、Marta Pontini、Beatrice Bechi、Nicholas J. Turner
DOI:10.1002/cctc.201301008
日期:2014.4
Amine oxidases are useful bio‐catalysts for the synthesis of enantiomerically pure 1°, 2° and 3° chiral amines. Enzymes in this class (e.g., MAO‐N from Aspergillus niger) reported previously have been shown to be highly S selective. Herein we report the development of an enantiocomplementary R‐selective amine oxidase based on 6‐hydroxy‐D‐nicotine oxidase (6‐HDNO) with broadened substrate scope and
Zinc‐Catalyzed Asymmetric Hydrosilylation of Cyclic Imines: Synthesis of Chiral 2‐Aryl‐Substituted Pyrrolidines as Pharmaceutical Building Blocks
作者:Izabela Węglarz、Karol Michalak、Jacek Mlynarski
DOI:10.1002/adsc.202001043
日期:2021.3.2
cyclic imines promoted by a chiral zinc complex is reported. In situ generated zinc‐ProPhenol complex with silane afforded pharmaceutically relevant enantioenriched 2‐aryl‐substituted pyrrolidines in high yields and with excellent enantioselectivities (up to 99% ee). The synthetic utility of presented methodology is demonstrated in an efficient synthesis of the corresponding chiral cyclic amines, being pharmaceutical
Enantioselective Imine Reduction Catalyzed by Phosphenium Ions
作者:Travis Lundrigan、Erin N. Welsh、Toren Hynes、Chieh-Hung Tien、Matt R. Adams、Kayelani R. Roy、Katherine N. Robertson、Alexander W. H. Speed
DOI:10.1021/jacs.9b07293
日期:2019.9.11
The first use of phosphenium cations in asymmetric catalysis is reported. A diazaphosphenium triflate, prepared in two or three steps on a multi-gram scale from commercially available materials catalyzes the hydroboration or hydrosilation of cyclic imines with enantiomeric ratios of up to 97:3. Catalyst loadings are as low as 0.2 mole percent. Twenty-two aryl/heteroaryl pyrrolidines and piperidines
An (<i>R</i>)-Imine Reductase Biocatalyst for the Asymmetric Reduction of Cyclic Imines
作者:Shahed Hussain、Friedemann Leipold、Henry Man、Elizabeth Wells、Scott P. France、Keith R. Mulholland、Gideon Grogan、Nicholas J. Turner
DOI:10.1002/cctc.201402797
日期:2015.2
enantiomerically pure chiral amines continues to expand, few existing methods provide access to secondary amines. To address this shortcoming, we have over-expressed the gene for an (R)-imine reductase [(R)-IRED] from Streptomyces sp. GF3587 in Escherichia coli to create a recombinant whole-cell biocatalyst for the asymmetricreduction of prochiral imines. The (R)-IRED was screened against a panel of cyclic imines
Reactions in Organic Synthesis Abstract Catalyzed by the complex generated in situ from iridium and the chiral ferrocene ligand, tert-butyl (4-oxo-4-arylbutyl)carbamate substrates were deprotected and then reductively cyclised to form 2-substituted arylpyrrolidines in a one-pot manner, in which the intramolecular reductive amination was the key step. A range of chiral 2-substituted arylpyrrolidines were