Installation of Amine Moieties into a Polycyclic Anodic Product Derived from 2,4-Dimethylphenol
作者:Joaquin Barjau、Jan Fleischhauer、Gregor Schnakenburg、Siegfried R. Waldvogel
DOI:10.1002/chem.201102722
日期:2011.12.23
4‐dimethylphenol is anodically treated, a dehydrotetramer with four contiguous stereocentres is readily obtained on a multi‐gram scale. The substitution of a 2,4‐dimethyl‐phenoxy fragment by several amines was demonstrated, and the best results were obtained with primary amines. Optically pure α‐chiral aliphatic amines yield diastereomeric mixtures that can be separated in most cases. The basic amine causes a
Directanodicoxidation of 2,4-dimethylphenol yields an unusual spiropentacyclic scaffold. An intermediate was isolated and structurally elucidated which strongly supports the postulated mechanism for the stereoselective formation of this spirolactone moiety. Additionally, we report an ameliorated protocol for the rearrangement to the spirolactone system.
Facile and Highly Diastereoselective Formation of a Novel Pentacyclic Scaffold by Direct Anodic Oxidation of 2,4-Dimethylphenol
作者:Itamar M. Malkowsky、Christina E. Rommel、Katrin Wedeking、Roland Fröhlich、Klaus Bergander、Martin Nieger、Claudia Quaiser、Ulrich Griesbach、Hermann Pütter、Siegfried R. Waldvogel
Diversity-Oriented Synthesis of Polycyclic Scaffolds by Modification of an Anodic Product Derived from 2,4-Dimethylphenol
作者:Joaquin Barjau、Gregor Schnakenburg、Siegfried R. Waldvogel
DOI:10.1002/anie.201006637
日期:2011.2.7
Like a Swiss army knife: The pentacycle shown, which results from the anodic oxidation of 2,4‐dimethylphenol, displays a wealth of potential reactivity. Depending on the applied reaction conditions a variey of polycyclic architectures are obtained with impressive stereo‐, regio‐, and chemoselectivity.
Synthesis and Isolation of Enantiomerically Enriched Cyclopenta[<i>b</i>]benzofurans Based on Products from Anodic Oxidation of 2,4-Dimethylphenol
作者:Michael Mirion、Lars Andernach、Caroline Stobe、Joaquin Barjau、Dieter Schollmeyer、Till Opatz、Arne Lützen、Siegfried R. Waldvogel
DOI:10.1002/ejoc.201500600
日期:2015.8
stereocentres on a multigram scale. The installation of propellanes on this scaffold using enantiomericallypure carbonyl compounds leads to a mixture of diastereomers. This mixture is easily separable using standard chromatography and gives rise to optically pure cyclopenta[b]benzofurans which are important scaffolds in a variety of natural products. The synthesis is easy to perform and allows a reliable access