Total synthesis of (.+-.)-cycloeudesmol and (.+-.)-epicycloeudesmol

Total Synthesis of Shearinines D and G: A Convergent Approach to Indole Diterpenoids

The first total syntheses of the indole diterpenoids (+)‐shearinine G and D are disclosed. The successful routes rely on late‐stage coupling of two complex fragments. Formation of the challenging trans‐hydrindane motif was accomplished by diastereoselective, intramolecular cyclopropanation. A one‐pot sequence consisting of Sharpless dihydroxylation/Achmatowicz reaction was developed to install the dioxabicyclo[3.2.1]octane motif. The indenone subunit was accessed by Prins cyclization. Tuning the electronic nature of the substituents on the parent arylcarboxaldehyde allowed access to divergent products that were further transformed into shearinines G and D. Riley‐type oxidation of a bicyclic enone yielded a surprising stereochemical outcome.

A copper-catalyzed formal O–H insertion reaction of α-diazo-1,3-dicarbonyl compounds to carboxylic acids with the assistance of isocyanide

Straightforward synthetic access to α-acyloxy-1,3-dicarbonyl compounds is described via a novel Cu(ii)-catalyzed and isocyanide-assisted formal O–H insertion reaction of α-diazocarbonyl compounds to carboxylic acids.