Mn(OAc)₃-Mediated Addition Reactions of NaSO₂CF₃ and Perhalogenated Carboxylic Acids with Unactivated Alkenes Conjectured by a Single Electron Transfer and Halogen Abstraction Mechanism

Abstract

A free-radical halotrifluoromethylation of olefins by using Mn-(OAc) 3 •2H 2 O, CF 3 SO 2 Na, and perhalogenated carboxylic acids has been achieved. Perhalogenated carboxylic acids act as a halogen source and CF 3 SO 2 Na acts as a CF 3 source. The reaction displayed good tolerance of functional groups in the substrates under mild conditions. The radical clock experiment and TEMPO inhibition experiment support a radical process. The halogen reagent competition experiment shows that the last step of halogenation process is mainly through a halogen abstraction mechanism.

Developing flow photo-thiol–ene functionalizations of cinchona alkaloids with an autonomous self-optimizing flow reactor

“…All reagents, starting materials and solvents were obtained from commercial suppliers and used as such without further purification, unless otherwise noted. High-field 1 H and 13 C NMR spectra were recorded at 300 or 400 and 75 or 100 MHz, respectively. 1 H and 13 C NMR spectra were referenced to the internal deuterated solvent (CDCl 3 ) at 7.26 and 77.16 ppm, respectively and coupling constants were measured in Hertz.…”

“…High-field 1 H and 13 C NMR spectra were recorded at 300 or 400 and 75 or 100 MHz, respectively. 1 H and 13 C NMR spectra were referenced to the internal deuterated solvent (CDCl 3 ) at 7.26 and 77.16 ppm, respectively and coupling constants were measured in Hertz. All chemical shifts were quoted in ppm, relative to TMS, using the residual solvent peak as a reference standard.…”

“…The functionalization of quinine 1a by carbon-centered radical species is also a standard process, but mostly limited to the introduction of fluorinated alkane chains. [10][11][12][13] The thiol-ene reaction is a chemical transformation involving the addition of an organic thiol to a double bond either through an ionic pathway if the double bond is a Michael acceptor, or through a free-radical approach. The thiol-ene reaction is a powerful transformation compatible with a large number of chemical functions and allowing the introduction of a wide structural diversity.…”

Recent Advances on the Halo- and Cyano-Trifluoromethylation of Alkenes and Alkynes

“…It should be mentioned that there were also some related reports on the halo-perfluoroalkylation of unsaturated bonds which just contained one example about trifluoromethylation [ 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 , 95 ].…”

Electrochemical Trifluoromethylation of Glycals

“…Mn II was first oxidized to Mn III at the anode. The CF 3 radical was produced from CF 3 SO 2 Na by the Mn III -mediated oxidation via a single -electron transfer (SET) process . The attack of the CF 3 radical onto the double bond of glucal 1a provided radical intermediate II , which could be further oxidized and transformed to glycosyl oxocarbenium ion III on the surface of an anode.…”