A new type of eight-membered ring N-heterocyclic carbene (NHC) bearing a rigid naphthalene moiety in the backbone is reported for the first time. Stereoelectronic properties of 4,5-dihydro-1H-naphtho[1,8-ef][1,3]diazocin-3(2H)-ylidene (NaphtDHD) and smaller ring NHCs were theoretically studied at the DFT level. Amidinium salts were prepared from corresponding amidines and dibromides. Free carbene NaphtDHD-Dipp (Dipp = 2,6-diisopropylphenyl) was generated in solution by treatment of the corresponding salt with LiHMDS. It is stable in solution at low temperatures, while decomposing rapidly at room temperature. Silver(i) and copper(i) complexes were synthesized and structurally characterized in the solid state. The copper(i) complex [(NaphtDHD-Mes)CuBr] (Mes = mesityl, 2,4,6-trimethylphenyl) exhibits high catalytic activity in alkyne-azide cycloaddition (CuAAC) reaction under solvent-free conditions.

Aqueous glycerol was identified as a renewable reaction medium for metalla‐electrocatalyzed C−H activation powered by sustainable energy sources. The renewable solvent was employed for cobalt‐catalyzed C−H/N−H functionalizations under mild conditions. The cobalta‐electrocatalysis manifold occurred with high levels of chemo‐ and positional selectivity and allowed for electrochemical C−H activations with broad substrate scope. The resource economy of this strategy was considerably substantiated by the direct use of renewable solar and wind energy.

A single catalyst for solvent-free Buchwald–Hartwig amination with both primary and secondary amines.

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We have found that expanded-ring NHC gold(i) complexes efficiently and regioselectively catalyze the hydration of alkylarylacetylenes in an anti-Markovnikov fashion due to steric repulsion build-up in the transition state, giving benzylalkyl ketones.

A new environmentally friendly approach to transition metal- and solvent-free amide synthesis from aryl esters and aryl amines is described.

Peyssonnoside A is a marine-derived sulfated diterpenoid glucoside with a unique 5/6/3/6 tetracyclic skeleton with a highly substituted cyclopropane ring deeply embedded into the structure. Herein, we report the first total synthesis of this natural product in a concise, efficient, scalable, and highly diastereoselective fashion. The aglucone peyssonnosol was synthesized in 21% overall yield after 15 steps, featuring a Simmons–Smith cyclopropanation and Mukaiyama hydration, fully controlled by the spatial structure of the substrates.

A thorough mechanistic investigation of the Pdcatalyzed and Ag-mediated cross-coupling of the monosubstituted tetrazine 3-bromo-1,2,4,5-tetrazine with boronic acids is reported. The study combines kinetic analyses, isolation of catalytic intermediates, and computational methods to gain insights into the mechanism. On the basis of these experimentally validated hypotheses, a highly electron-deficient ligand was predicted to overcome the challenge of coupling previously unfeasible substrates, which in turn was confirmed experimentally. In addition, a data-driven workflow was applied to study how the mechanistic understanding impacts the generality of the scope.