A general electron donor–acceptor complex for photoactivation of arenes via thianthrenation

Abstract

General photoactivation of electron donor–acceptor (EDA) complexes between arylsulfonium salts and 1,4-diazabicyclo[2.2.2]octane with visible light or natural sunlight was discovered. This practical and efficient mode enables the production of aryl...

Selective Fluorosulfonylation of Thianthrenium Salts Enabled by Electrochemistry

“…On the basis of the results presented above and considering that our model reaction was performed at voltages of −1.5 to 2.0 V, we envisioned that 1a could be facilely reduced to an aryl radical under our optimal conditions, similar to some recent light-promoted examples . To probe the existence of such an aryl radical, radical scavenger 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) was added to reaction mixture under optimal conditions, and we found that only trace amounts of 3a were detected, along with two radical adducts, 6 and 7 , detected by HRMS (Scheme A) .…”

Organothianthrenium salts: synthesis and utilization

“…Using the same strategy, Yu developed a photoinduced C–H arylation of N-containing heterocycles using arenes by thianthrenation ( Scheme 24 ). 90 The reaction efficiently and selectively functionalized bioactive molecules with structurally complex drugs or agricultural pharmaceuticals. The proposed mechanism shows that DABCO interacted with thianthrenium salts to form an EDA complex, which generated aryl radicals, thianthrene, and DABCO˙ + via single electron transfer.…”

Visible light-promoted, photocatalyst-free decarboxylative alkylation of 2H-indazoles via electron donor–acceptor complex activation

“…The EDA complex strategy has attracted considerable attention in recent years owing to the concomitant circumvention of the requirement of a photocatalyst and stoichiometric oxidant. [24][25][26][27][28][29][30][31][32][33][34][35] The electron-rich donor and the electron-deficient acceptor form a molecular aggregate through non-covalent interaction, which generates valuable radicals through visible light-mediated single electron transfer (SET). In 2019, the elegant works of Shang, Fu, and co-workers revealed that triphenylphosphine (PPh 3 ) and sodium iodide (NaI) systems could be used for photocatalytic alkylation.…”