Controlled access to resveratrol-based natural products is offered by a novel, modular concept. A common building block readily available on a large scale serves as the starting material for the introduction of structurally important aryl groups by a Pd-catalyzed decarboxylative arylation and an oxidative Heck reaction with good yields and high stereoselectivity. The modular approach is convincingly documented by the successful synthesis of three racemic resveratrol-based natural products (quadrangularin A, ampelopsin D, and pallidol).

Short and highly efficient stereoselective syntheses provide machaeriols and cannabinoids in a divergent approach starting from a common precursor, commercially available (S)-perillic acid. Key features of the novel strategy are a stereospecific palladium-catalyzed decarboxylative arylation and a one-pot sequence comprising a stereoselective hydroboration followed by oxidation or reduction of the corresponding intermediary boranes. The divergent approach is convincingly demonstrated by the five-step syntheses of (+)-machaeriol B, (+)-machaeriol D, and related analogues, and the four-step synthesis of (+)-Δ(8)-THC and an analogue.

A convenient protocol for the smooth conversion of the resistant P-O bond in phosphane oxides into a reactive P-N bond of synthetically useful pyrazolylphosphonium salts is described. A highly charged, oxophilic, phosphorus-centered trication is employed and the reactions are conducted at room temperature with quantitative yields. The resulting pyrazolylphosphonium cations are valuable synthetic intermediates and are used for the synthesis of a variety of organophosphorus compounds. This represents a new approach towards the transformation of the rather inert phosphoryl group under very mild reaction and workup conditions and aims towards alternatives to existing reduction methods for phosphane oxide functionalization.

A new cascade reaction involving an intramolecular Michael addition followed by an alkyne carbocyclization is presented. The reaction is promoted by a substoichiometric amount of KHMDS and represents one of the rare examples where the carbocyclization of an unactivated alkyne is mediated by an alkali metal base, under mild conditions. The reaction allows the generation of functionally dense, stereochemically defined, tricyclic structures possessing three adjacent stereocenters in good yields and with high stereoselectivity.

Machaeriols and cannabinoids can be synthesized by a short and divergent approach featuring highly efficient stereoselective transformations from a common precursor, commercially available (S)‐perillic acid. In their Communication on A. Studer and F. Klotter report the use of a stereospecific palladium‐catalyzed decarboxylative γ‐arylation and a one‐pot sequence comprising a stereoselective hydroboration followed by oxidation or reduction as key steps.

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Going uphill: The diverse chemistry established for phosphorus is mainly focused on neutral or anionic examples. Therefore, an extension of research efforts towards cationic phosphorus compounds would be desirable. However, the preparation of such compounds is restricted because of synthetic limitations. In their Full Paper on page 1805, Jan J. Weigand and co-workers at the University of Münster describe a new method for the conversion of phosphane oxides into synthetically useful cationic organophosphorus compounds using a highly-charged phosphorus-centered trication under very mild reaction and work-up conditions. Furthermore, the protocol developed for the reaction might also be applicable for the transformation of functional phosphane oxides, implementing a novel synthetic route to tertiary phosphanes that are used as ligands in transition-metal-mediated reactions.

Ein kurzer und divergenter Syntheseweg mit hoch effizienten stereoselektiven Umsetzungen liefert Machaeriole und Cannabinoide aus einer gemeinsamen Vorstufe, der kommerziell erhältlichen (S)‐Perillasäure. Schlüsselschritte des neuen Ansatzes sind eine stereospezifische Pd‐katalysierte decarboxylierende Arylierung und eine Eintopf‐Sequenz aus stereoselektiver Hydroborierung mit anschließender Oxidation bzw. Reduktion der Boran‐Intermediate. Die divergente Strategie ließ sich überzeugend für je fünfstufige Synthesen von (+)‐Machaeriol B, (+)‐Machaeriol D sowie zugehörigen Analoga und für eine vierstufige Sequenz zu (+)‐Δ8‐THC und einem seiner Derivate heranziehen.