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.

The anodic treatment of 2,4‐dimethylphenol offers a powerful and direct method for the construction of a dehydrotetramer with four contiguous stereocentres on a multigram scale. The installation of propellanes on this scaffold using enantiomerically pure 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 to chiral compounds with very high enantiomeric excess. It was possible to determine the absolute configuration of these compounds by comparison of experimentally recorded and calculated VCD spectra of all enantiomers.

When 2,4-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 partial hemiketal-opening of the bisbenzofuran moiety leading to an equilibrium within an α,β-unsaturated cyclohexenone. This dynamic behaviour occurs on the time scale of NMR spectroscopy and is also found by X-ray analysis providing a consistent picture.

Ähnlich wie ein Schweizer Taschenmesser kann ein anodisch aus 2,4‐Dimethylphenol erhaltenes Zwischenprodukt (siehe Strukturformel) je nach Reaktionsbedingungen stereo‐, regio‐ und chemoselektiv zu neuen polycyclischen Phenoloxidations‐Architekturen umgesetzt werden. Diese komplexen Strukturen sind über wenige Stufen gut erhältlich und haben unterschiedliche Funktionen.

Direct anodic oxidation 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.