A selenium-catalysed para-hydroxylation of N-arylhydroxamic acids is reported. Mechanistically, the reaction comprises an NÀO bond cleavage and consecutive seleniuminduced [2,3]-rearrangement to deliver para-hydroxyaniline derivatives. The mechanism is studied through both 18 Ocrossover experiments as well as quantum chemical calculations. This redox-neutral transformation provides an unconventional synthetic approach to para-aminophenols.

The highly strained tricyclo[5.2.1.0(1,6)]decene skeleton of solanoeclepin A was synthesized through two key C-C bond forming processes; thus, a Hg(TFA)2-mediated oxymercuration followed an intramolecular aldol reaction to B and a SmI2-mediated cyclization of C between an aldehyde and an unsaturated ester to form the cyclobutane D having a tricyclo[5.2.1.0(1,6)]dodecene.

An improved synthesis of rings DEF of solanoeclepin A has been achieved from ent-Hajos Parrish ketone. A key tricyclo[5.3.2.0]decene intermediate having an additional vinyl group as a precursor of a hydroxyl functionality was synthesized, in which the key steps included (i) a [2,3]-Wittig rearrangement to provide trans-hydroindene with C11(R)-configuration, (ii) the introduction of a vinyl group as a masked OH at C6, (iii) an oxymercurative aldol to synthesize the tricyclo[5.3.2.0]decene moiety, (iv) an oxidative C-C bond cleavage to yield an aldehyde and an unsaturated methyl ketone, and (v) a radical cyclization for the cyclobutane ring formation to provide the tricyclo[5.2.1.0]decene compound.

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Über eine Selen‐katalysierte para‐Hydroxylierung von N‐Arylhydroxamsäuren wird berichtet. Mechanistisch verläuft diese über N‐O‐Bindungsbruch und nachfolgende Selen‐induzierte [2,3]‐Umlagerungen um para‐Hydroxylanilinderivate zu erzeugen. Der Mechanismus wurde sowohl mittels 18O‐Überkreuzungsexperimenten als auch quantenchemischen Berechnungen untersucht. Diese redox‐neutrale Transformation ermöglicht einen ungewöhnlichen synthetischen Zugang zu para‐Aminophenolen.