Photoredox-catalyzed coupling of acyl oxime acetates with thiophenols to give arylthioesters in water at room temperature

Abstract

Photoredox catalysis in water has been receiving increasing attention due to its merits of being enviromental friendly, inexpensive, and safe. However, efficient approach to thioesters via photoredox catalysis in water...

Chromium-catalyzed allylic defluorinative acylation of trifluoromethyl-substituted alkenes with acyl oxime esters

“…of zinc in 1 mL solvent under N 2 atmosphere at 40 °C for 12 h. b Combined yields of the isolated products 3aa and 3aa′ after column chromatography. c Determined by 19 F NMR spectroscopy. d Not determined.…”

“…of zinc in 1 mL MeCN/DMA (3 : 1) under N 2 atmosphere at 40 °C for 12 h. b Yields of the isolated products after column chromatography. c The ratios of 3 to 3′ are determined to be >99 : 1 by 19 F NMR spectroscopy. d The reaction was performed on a 2 mmol scale of 1a.…”

“…In 2019, Wu et al disclosed that acyl radicals can be generated from acyl oxime esters via photocatalyst-mediated reduction. 14 Relying on this discovery, acyl oxime derivatives have been successfully utilized as an acyl radical precursor in various acylation reactions of alkenes, 15 alkynes, 16 arenes, 17 isocyanides, 18 or thiophenols 19 under photocatalytic conditions in the last lustrum (Scheme 1B). Inspired by these elegant works and our ongoing research interest in transition metal-catalyzed reductive allylic defluorinative reactions, we envisioned a chromium-catalyzed 20,21 allylic defluorinative acylation reaction of trifluoromethyl-substituted olefins with acyl oxime esters as the acylating agent towards the synthesis of gem -difluoroalkenes containing a synthetically useful ketone group under mild reductive conditions (Scheme 1C).…”

Recent Advances in Visible‐Light‐Driven C−S Bond Formation

“…Thioesters are important molecular scaffolds in drug, natural products and organic transformation due to its biological properties and versatile reactivity [44] . In 2022, Huang and co‐workers developed the Eosin‐Y photoredox‐catalyzed coupling of acyl oxime acetates with thiophenols in water (in the presence of MPEG‐550 as the phase transfer catalyst) to afford aromatic thioesters in satisfactory yields [45] …”

“…[44] In 2022, Huang and co-workers developed the Eosin-Y photoredox-catalyzed coupling of acyl oxime acetates with thiophenols in water (in the presence of MPEG-550 as the phase transfer catalyst) to afford aromatic thioesters in satisfactory yields. [45] Synthesis of organic sulfides from thiols via radical induced cyclization. Several 2-sulfenylindoles (12.3, Scheme 12), some of them exhibiting biological activity as antiviral, [46] have been prepared through a visible-light driven radical cascade reaction between ortho-substituted arylisocianides 12.1 and thiols (e. g. thiophenol PhSH) in the presence of Ru(bpy) 2 + as the photoredox catalyst and an aromatic amine (e. g. paratoluidine 12.2) as the cocatalyst.…”