Biocatalytic Cascade for the Synthesis of Enantiopure β-Azidoalcohols and β-Hydroxynitriles
作者:Joerg H. Schrittwieser、Iván Lavandera、Birgit Seisser、Barbara Mautner、Wolfgang Kroutil
DOI:10.1002/ejoc.200900091
日期:2009.5
one-pot reaction sequence starting from prochiral α-chloroketones leading to enantiopure β-azidoalcohols and β-hydroxynitriles is described. Asymmetric bioreduction of α-chloroketones by hydrogen transfer catalysed by an alcohol dehydrogenase (ADH) established the stereogenic centre in the first step to furnish enantiopure chlorohydrin intermediates. Subsequent biocatalysed ring closure to the epoxide
An operationally simple and environmentally benign protocol for a highly regio‐ and chemoselective preparation of β‐substituted alcohols by means of ring‐opening reactions of oxiranes with various aliphatic alcohols, H2O, NaN3, and NaCN as nucleophiles in the presence of catalytic amounts of zirconium tetrakis(dodecyl sulfate) as Lewis acid/surfactant‐combined catalysts (LASCs) was developed. The high
Activation of Carboxylic Acids in Asymmetric Organocatalysis
作者:Mattia Riccardo Monaco、Belén Poladura、Miriam Diaz de Los Bernardos、Markus Leutzsch、Richard Goddard、Benjamin List
DOI:10.1002/anie.201400169
日期:2014.7.1
association of carboxylicacids with chiral phosphoric acid catalysts as a new activation principle for organocatalysis. This self‐assembly increases both the acidity of the phosphoric acid catalyst and the reactivity of the carboxylicacid. To illustrate this principle, we apply our concept in a general and highly enantioselective catalytic aziridine‐opening reaction with carboxylicacids as nucleophiles
Copper-Catalyzed Ring-Opening Reactions of Alkyl Aziridines with B2pin2: Experimental and Computational Studies
作者:Lucilla Favero、Andrea Menichetti、Cosimo Boldrini、Lucrezia Margherita Comparini、Valeria Di Bussolo、Sebastiano Di Pietro、Mauro Pineschi
DOI:10.3390/molecules26237399
日期:——
bonds with aziridines using diboron derivatives continues to be a particularly challenging field in view of the direct preparation of functionalized β-aminoboronates, which are important compounds in drug discovery, being a bioisostere of β-aminoacids. We now report experimental and computational data that allows the individuation of the structural requisites and of reaction conditions necessary to open
Combining Designer Cells and Click Chemistry for a One-Pot Four-Step Preparation of Enantiopure β-Hydroxytriazoles
作者:Wiktor Szymanski、Christiaan P. Postema、Chiara Tarabiono、Florian Berthiol、Lachlan Campbell-Verduyn、Stefaan de Wildeman、Johannes G. de Vries、Ben L. Feringa、Dick B. Janssen
DOI:10.1002/adsc.201000502
日期:2010.9.10
The multistep catalytic process using designercells, either added as freshly prepared suspensions or as stable lyophilized powder, and click reaction can be performed in one pot. The sequence of four reactions allows the production of both enantiomers of β‐hydroxytriazoles with high enantiomeric excess.