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The first site‐selective electrochemical alkylation of tropones is realized by reacting 2‐acetoxytropones and redox‐active‐esters (RAEs). The electroreductive protocol enables the preparation of mono‐ and disubstituted tropones in high yields (up to 71%) under very mild conditions. Dedicated voltammetric measurements served for the identification of 2‐acetoxytropones as a class of valuable trapping agents of nucleophilic radical species and shed light on the whole mechanistic profile. Wide tolerance towards functional groups (27 examples) and application to late‐stage functionalization of a bioactive compound (i. e. Colchicine analogue), emphasize the synthetic impact of the present methodology. [ABSTRACT FROM AUTHOR]

The "self-adaptability" of galvanostatic electrolysis was shown to assist a multistage unprecedented chemo- and diastereoselective electrochemically promoted cyclodimerization of chalcones. The process, all involving the reductive events, delivered densely functionalized cyclopentanes featuring five contiguous stereocenters (25 examples, yields of up to 95%, dr values up to >20 : 1). Dedicated and combined experimental as well as electrochemical investigation revealed the key role of a dynamic kinetic resolution of the aldol intermediate for the reaction mechanism. [ABSTRACT FROM AUTHOR]

A carboxylative Ni-catalyzed tandem C–C σ-bond activation of cyclobutanones followed by CO2-electrophilic trapping is documented as a direct route to synthetically valuable 3-indanone-1-acetic acids. The protocol shows an adequate functional group tolerance and useful chemical outcomes (yield up to 76%) when AlCl3 is adopted as an additive. Manipulations of the targeted cyclic scaffolds and a mechanistic proposal based on experimental evidence complete the investigation. [ABSTRACT FROM AUTHOR]

A dehydrogenative functionalization of styryl carbon‐carbon double bonds with triflamide is described via dual visible‐light photoredox/cobaloxime catalysis. A range of allylic triflamides (20 examples) were isolated in moderate to good yields (up to 88%) under stoichiometric acceptorless conditions. Dedicated labelling, as well as spectroscopic experiments, enabled to shed light on the concatenated photo‐ and chemo‐catalytic cycles. [ABSTRACT FROM AUTHOR]

A novel asymmetric nickel‐based procedure has been developed in which CO2 fixation is achieved as a second step of a truncated Heck coupling. For this, a new chiral ligand has been prepared and shown to achieve enantiomeric excesses up to 99 %. The overall process efficiently furnishes chiral 2,3‐dihydrobenzofuran‐3‐ylacetic acids, an important class of bioactive products, from easy to prepare starting materials. A combined experimental and computational effort revealed the key steps of the catalytic cycle and suggested the unexpected participation of Ni(I) species in the coupling event. [ABSTRACT FROM AUTHOR]

A catalytic system comprising a gold(I) complex with an N‐heterocyclic carbene (NHC) ligand in an ionic liquid as solvent exhibits higher catalytic efficiency compared to state of the art systems in the title reaction, which enables using down to 0.01 mol % gold. A commercial gold(I) catalyst such as IPrAuNTf2 can be employed for this purpose. In the case of less reactive substrates bearing electron‐withdrawing substituents at the phenol moiety, a tailor made NHC‐gold(I) precatalyst exhibits improved reactivity and can be advantageously employed compared to the commercial one. [ABSTRACT FROM AUTHOR]

A carbonylation-carboxylation synthetic sequence, via double CO 2 fixation, is described. The productive merger of a Ni-catalyzed cross-electrophile coupling manifold, with the use of AlCl 3 , triggered a cascade reaction with the formation of three consecutive C-C bonds in a single operation. This strategy traces an unprecedented synthetic route to ketones under Lewis acid assisted carbon dioxide valorization. Computational insights revealed a unique double function of AlCl 3 , and labeling ( 13 CO 2 ) experiments validate the genuine incorporation of CO 2 in both functional groups.

A carboxylative Ni-catalyzed tandem C-C σ-bond activation of cyclobutanones followed by CO 2 -electrophilic trapping is documented as a direct route to synthetically valuable 3-indanone-1-acetic acids. The protocol shows an adequate functional group tolerance and useful chemical outcomes (yield up to 76%) when AlCl 3 is adopted as an additive. Manipulations of the targeted cyclic scaffolds and a mechanistic proposal based on experimental evidence complete the investigation.

A novel asymmetric nickel-based procedure has been developed in which CO 2 fixation is achieved as a second step of a truncated Heck coupling. For this, a new chiral ligand has been prepared and shown to achieve enantiomeric excesses up to 99 %. The overall process efficiently furnishes chiral 2,3-dihydrobenzofuran-3-ylacetic acids, an important class of bioactive products, from easy to prepare starting materials. A combined experimental and computational effort revealed the key steps of the catalytic cycle and suggested the unexpected participation of Ni(I) species in the coupling event., (© 2021 Wiley-VCH GmbH.)