Rhodium(I)‐Catalyzed Decarbonylative Spirocyclization through C?C Bond Cleavage of Benzocyclobutenones: An Efficient Approach to Functionalized Spirocycles

The rhodium‐catalyzed formation of all‐carbon spirocenters involves a decarbonylative coupling of trisubstituted cyclic olefins and benzocyclobutenones through C C activation. The metal–ligand combination [{Rh(CO)₂Cl}₂]/P(C₆F₅)₃ catalyzed this transformation most efficiently. A range of diverse spirocycles were synthesized in good to excellent yields and many sensitive functional groups were tolerated. A mechanistic study supports a hydrogen‐transfer process that occurs through a β‐H elimination/decarbonylation pathway.     

Transition‐Metal‐Free Acceptorless Decarbonylation of Formic Acid Enabled by a Liquid Chemical‐Looping Strategy

The selective decarbonylation of formic acid was achieved under transition‐metal‐free conditions. Using a liquid chemical‐looping strategy, the thermodynamically favored dehydrogenation of formic acid was shut down, yielding a pure stream of CO with no H₂ or CO₂ contamination. The transformation involves a two‐step sequence where methanol is used as a recyclable looping agent to yield methylformate, which is subsequently decomposed to carbon monoxide using alkoxides as catalysts.     

Bestimmung einiger Derivate der Ameisens?ure

Ohne Zusammenfassung

---

Determination of some derivatives of formic acid

     

κ3‐(N^C^C)Gold(III) Carboxylates: Evidence for Decarbonylation Processes

Gold(III) carboxylate species, stabilized by a κ³‐(N^C^C) ligand template, are presented herein. A η¹‐Au^III‐C(O)‐OH species has been characterized under cryogenic conditions as a result of the nucleophilic attack of an ammonium hydroxide onto a dinuclear μ‐CO₂‐κ³‐(N^C^C)Au^III precursor. Thermal decomposition for these species proceeds by an unusual decarbonylation process, in contrast to typical decarboxylation pathways observed in related metallocarboxylic acids.