Photochemical Organocatalytic Aerobic Cleavage of C═C Bonds Enabled by Charge-Transfer Complex Formation

Abstract

A novel visible-light-driven organocatalytic protocol to access aerobic oxidative cleavage of olefins, promoted by sodium benzene sulfinate, is described herein. An array of alkenes smoothly delivered the corresponding aldehydes and ketones under transition-metal-free conditions. Notably, α-halo-substituted styrenes proceeded with photoinduced oxidation to finally afford α-halo-acetophenones with halogen migration. Crucial to this oxidation was the formation of charge-transfer complexes between sodium benzene sulfinate with molecular O2 to ultimately deliver the carbonyl products.

Palladium-Catalyzed Regioselective C3-Allylic Alkylation of 2-Aryl Imidazopyridines with MBH Carbonates

“…All α-bromo acetophenone derivatives were prepared using previous literature precedent, and characterization data of the compounds such as Br-int of 1a , 1b , 1c , 1d , 1e , 1f , 1g , and 1h were found to match with previous reports.…”

Photoinduced Oxygen Transfer Using Nitroarenes for the Anaerobic Cleavage of Alkenes

“…While this synthetic advance complements ozonolysis, this approach is conducted under highly oxidative conditions that limit the reaction scope and produce large amounts of toxic waste. , Considering these limitations, development of a mild, general, and practical approach toward the oxidative cleavage of alkenes is highly warranted. More recently, transition-metal and organic photocatalytic methods have been developed. − However, these approaches often rely on molecular oxygen as the terminal oxidant, which limits the reaction scope. Herein, we report a visible light-induced anaerobic cleavage of alkenes to generate carbonyl compounds using economical and bench-stable nitroarenes as oxygen transfer reagents (Scheme C).…”

Photoinduced Oxygen Transfer using Nitroarenes for the Anaerobic Cleavage of Alkenes

“…More recently, transition metal and organic photocatalytic methods have been developed. [7][8][9] However, these approaches often rely on molecular oxygen as the terminal oxidant, which limits the reaction scope. Herein, we report a visible light-induced anaerobic cleavage of alkenes to generate carbonyl compounds using inexpensive and bench-stable nitroarenes as oxygen transfer reagents in a user-friendly protocol (Scheme 1C).…”