Chlorine-radical-mediated C–H oxygenation reaction under light irradiation

Abstract

The oxygenation of C(sp3)–H bonds is a key chemical reaction in the production of fine chemicals and pharmaceuticals. Hydrogen atom transfer has recently gained significant attention for its ability to...

Visible light-mediated synthesis of quinazolinones and benzothiadiazine-1,1-dioxides utilizing aliphatic alcohols

“…Based on various control experiments and previous literature reports, 26–35 a possible mechanism was proposed for the synthesis of quinazolinones (Fig. 3).…”

High conversion of methane to methyl ester at 298 K

“…Meanwhile, another byproduct, formic acid (HCO 2 H) will be readily generated in the further reactions of CH 3 -OO• species. 34,35,43 Fortunately, CH 3 -OO• can also react with NO to quickly give CH 3 -OO-NO in the gas-phase, and CH 3 -OO-NO could be isomerized to methyl nitrate (CH 3 O-NO 2 ) as a protected species to prevent overoxidations happening under same conditions, 44,45 which is a key step for product selectivity. This implies that the selectivity of methyl ester in the gas-phase depends on the ratio of NOCl/ CH 4 /O 2 , and NOCl is from NO 2 − or NO 3 − with HCl in the liquidphase.…”

“…Using the chlorine radical to give CH 3 –OO· species, Ohkubo and co-workers obtained a high yield of methane oxides, mainly as formic acid. 34,35 However, there are few reports which disclose how to convert CH 3 –OO· species to methanol or a methyl ester exclusively, 36,37 to prevent over-oxidations of methanol or methyl ester happening in the liquid-phase and to devise a chlorine catalytic system for the aerobic oxidation of methane under radical reaction conditions.…”

Enhanced Reactivity of Acridinium Perchlorate: Harnessing Redox Mediators for Trace Chloride Activation in Hydrogen Atom Transfer Photocatalysis

“…3−5 Various indirect HAT methods have been explored, employing transient heteroatom radicals such as thiol radicals, 6,7 halogen radicals, 8−10 nitrogen radicals, 11,12 and oxygen radicals. 13,14 Among them, chlorine radical (Cl•) has long been recognized for its efficacy in photochemical alkane functionalization, 15,16 and continues to find industrial use in chlorination processes 17 due to the high bond dissociation energy (BDE) of H−Cl (103 kcal/mol). 18 Both ligand-to-metal charge transfer (LMCT) and singleelectron transfer (SET) methods have been successfully employed for the formation of Cl•.…”