Copper-Promoted Trifluoromethanesulfonylation and Trifluoromethylation of Arenediazonium Tetrafluoroborates with NaSO₂CF₃

Abstract

A tunable chemoselective trifluoromethanesulfonylation and trifluoromethylation of arenediazonium tetrafluoroborates with Langlois' reagent (NaSO2CF3) was developed. The Cu2O-catalyzed reaction in DMSO gave aryl trifluoromethanesulfones as the major products. On the other hand, the trifluoromethylated arenes were produced in the presence of oxidant tert-butyl hydroperoxide, CuBF4(MeCN)4, and 2,2';6',2″-terpyridine (tpy). Both of these transformations proceed under mild conditions and tolerate functional groups.

Copper‐Promoted Ritter‐Type Trifluoroethoxylation of (Hetero)arenediazonium Tetrafluoroborates: A Method for the Preparation of Trifluoroethyl Imidates

“…Our group recently reported the copper‐promoted trifluoromethanesulfonylation and trifluoromethylation of arenediazonium tetrafluoroborates with CF 3 SO 2 Na for the preparation of CF 3 SO 2 ‐ and CF 3 ‐containing arenes . As an extension of this work, we wanted to apply this protocol for the preparation of CF 3 CH 2 O‐containing arenes.…”

Copper‐Mediated Di‐ and Monofluoromethanesulfonylation of Arenediazonium Tetrafluoroborates: Probing the Fluorine Effect

“…[4a,4d] Recently, we were interested in two reports on the preparation of trifluoromethyl aryl sulfones from sodium trifluoromethanesulfinate (CF 3 SO 2 Na). [9,10] In 2013, Shekhar and co-workers reported a copper-catalyzed coupling of aryl iodonium salts with CF 3 SO 2 Na (Scheme 1, eq 1). [9] In 2015, Qing and co-workers reported a copper-promoted coupling of arenediazonium tetrafluoroborates with sodium trifluoromethanesulfinate (Scheme 1, eq 2).…”

“…[9] In 2015, Qing and co-workers reported a copper-promoted coupling of arenediazonium tetrafluoroborates with sodium trifluoromethanesulfinate (Scheme 1, eq 2). [10] In these reactions, both iodonium salts and arenediazonium tetrafluoroborates are not able to oxidize CF 3 SO 2 Na to generate trifluoromethyl radical. Indeed, when an external oxidant (such as t-BuOOH) is used, CF 3 SO 2 Na can be oxidized to give trifluoromethyl radical and a trifluoromethylation (rather than trifluoromethanesulfonylation) reaction takes place.…”

Copper‐Promoted One‐Pot Trifluoromethylation of Aromatic Amines with Togni′s Reagent

“…The conversion of amine group into halogen, named the Sandmeyer reaction, is the most prominent method for functional group transformation. Very recently, five groups have added new content to this century‐old transformation independently by replacing nucleophilic halogen with “CF 3 ” species (Scheme b) . Such Sandmeyer‐type reactions have proven to be efficient strategy to introduce trifluoromethyl group into the aromatic rings.…”

“…Grushin's group demonstrated the trifluoromethylation of aromatic diazonium salts with fluoroform‐derived CuCF 3 in aqueous media for the first time . Qing and Xu reported the copper‐promoted trifluoromethylation of ArN 2 + BF 4 − with NaSO 2 CF 3 (Langlois′ reagent) in the presence of TBHP . All these transformations can be conducted under mild conditions and tolerated various functional groups.…”