Radical Carbofluorination of Unactivated Alkenes with Fluoride Ions

Abstract

The copper-assisted radical carbofluorination of unactivated alkenes with fluoride ions is described. With [Cu(L3)F]HO (L3 = 4,4'-di(methoxycarbonyl)-2,2'-bipyridine) as the fluorine source and [Ag(DMPhen)(MeCN)]BF (DMPhen = 2,9-dimethyl-1,10-phenanthroline) as the chloride scavenger, the reaction of unactivated alkenes with CCl in acetonitrile provided the corresponding carbofluorination products in satisfactory yields. The protocol exhibited a wide functional group compatibility and broad substrate scope and could be extended to the use of a variety of activated alkyl chlorides other than CCl. A copper-catalyzed fluorotrifluoromethylation of unactivated alkenes was then successfully developed with CsF as the fluorine source and Umemoto's reagent as the trifluoromethylating agent. A mechanism involving the fluorine atom transfer from Cu(II)-F complexes to alkyl radicals is proposed.

Synergistic photoredox and copper catalysis by diode-like coordination polymer with twisted and polar copper–dye conjugation

“…Addition of the CF 3 radical to the olefinic site nearby the docked carbonyl 7l occurs via transition state TS I by an energy barrier of 16.76 kcal mol −1 to form carbon-centred radical intermediate II . Subsequently, the chloride anion coordinates to the copper centre and replaces the carbonyl moiety, and the copper–Cl species mediates Cl-atom transfer to form 8l 53 . The overall transformation via pathway a is exergonic by 12.19 kcal mol − 1 .…”

Mediator and Additive Free Trifluoromethyl‐Fluorination of Terminal Alkenes by Persistent Perfluoroalkyl Radical

“…There are only two recent literature reports which can be considered as one step trifluoromethyl‐fluorination reactions of olefins. Both these methods are based on complex reactions of terminal alkenes, which involve radical and oxidative steps, with either TMSCF 3 /CsF/PhI(OAc) 2 /AgOTf/Selectfluor system or S‐(trifluoromethyl)dibenzothiophenium tetrafluoroborate (the Umemoto reagent)/CsF/Cu(OTf) 2 /bathocuproine/4,4′‐di(methoxycarbonyl)‐2,2′‐bipyridine system under visible light irradiation …”

Copper’s rapid ascent in visible-light photoredox catalysis

“…Along these lines, Yu, Li, and co-workers have recently demonstrated a remarkable fluorine atom-transfer (FAT) capability of an innovative Cu(II)-F complex to efficiently promote carbofluorination of unactivated olefins (Fig. 2B, iii) (23). The reaction proceeds in the presence of CsF as the F-source, Umemoto's reagent, 5-(trifluoromethyl)dibenzothiophenium tetrafluoroborate, as the CF 3 -source, and Cu(OTf) 2 as the catalyst, with the assistance of two ligands: bathocuproine (BC) to reduce Cu(II) to Cu(I) and electron-deficient 4,4′-di(methoxycarbonyl)-2,2′bipyridine (bpydc) to accelerate FAT from the LCu(II)-F complex.…”