Direct Phosphorus‐Induced Fluoroalkylthiolation with Fluoroalkylsulfonyl Chlorides

Abstract

As imple and practical method of fluoroalkylthiolation using fluoroalkylsulfonyl chlorides (R f SO 2 Cl, R f = CF 3 ,C 4 F 9 ,C 8 F 17 ,C F 2 Ha nd CH 2 CF 3 ) has been developed. These easy-to-handle reagents are powerful and can be used for electrophilic fluoroalkylthiolation of electron-rich arenesa nd thiols using diethyl phosphitea sr educing agent.

Selective Trifluoromethylthiolation and Trifluoromethylsulfinylation of Indoles with Sodium Trifluoromethanesulfinate Promoted by Phosphorus Reagents

“…On the basis of the experimental results above and previous reports, [11][12][13][14][15]22] it can be deduced that CF 3 SCl and CF 3 SOCl are formed as key intermediates in the reaction and undergo subsequent trifluoromethylthiolation and trifluoromethylsulfinylation, respectively, with 1. It can be inferred that the formation of 2a versus 3a is a competitive process.…”

“…[9] In addition, a new trifluoromethylthiolation strategy has recently emerged that involves the combination of trifluoromethanesulfonyl chloride (CF 3 SO 2 Cl) and a reducing reagent, such as PMe 3 , [10] (EtO) 2 P(O)H, [11] or CF 3 SO 2 Cl/ PPh 3 . Previously, several mild and efficient CF 3 SN-and CF 3 SO-based electrophilic trifluoromethylthiolating reagents were developed and employed with great success in a range of trifluoromethylthiolation reactions.…”

Transition-metal-free trifluoromethylthiolation and difluoromethylthiolation of thiols with trifluoromethanesulfonyl chloride and difluoromethanesulfonyl chloride

“…However, during the course of our manuscript preparation, Yi reported the direct trifluoromethylthiolation of thiols using CF 3 SO 2 Cl as the trifluoromethylthiolation reagent and diethyl phosphonate as the reducing agent at 90 C (Scheme 1, equation (5)). 14 We report herein a metal-free direct trifluoromethylthiolation and difluoromethylthiolation of aromatic thiols by CF 3 SO 2 Cl and CHF 2 SO 2 Cl, respectively, in the presence of PPh 3 at room temperature (Scheme 2). The use of the iodide salt in our method allows the reaction to proceed at a lower temperature as compared to that in Yi's protocol.…”

Organophosphorus‐Catalyzed Deoxygenation of Sulfonyl Chlorides: Electrophilic (Fluoroalkyl)sulfenylation by PIII/PV=O Redox Cycling

“…[3] By contrast, the complementary deoxygenative OATf rom high-valent organosulfur oxides has generally been viewed with less strategic synthetic importance. [5] In this vein, recent work by the groups of Shibata and Cahard, [6] Liu, [7] and Zhao [8] reflects the synthetic potential of this approach by the use of phosphorus derivatives as oxygen acceptors,a llowing access to valuable and reactive sulfenyl electrophiles from the more readily handled sulfonyl congener. [5] In this vein, recent work by the groups of Shibata and Cahard, [6] Liu, [7] and Zhao [8] reflects the synthetic potential of this approach by the use of phosphorus derivatives as oxygen acceptors,a llowing access to valuable and reactive sulfenyl electrophiles from the more readily handled sulfonyl congener.…”

“…[15] With the aforementioned biphilic phosphetane-based catalytic system (20 mol %o f2·[O],2 equiv of PhSiH 3 ), the catalytic deoxygenation of CF 3 SO 2 Cl in 1,4-dioxane containing indole (1)r esulted in the regioselective C3-trifluoromethylsulfenylation product 12 in quantitative yield ( Table 1, entry 1). Alteration of the identity of the exocyclicPsubstituent of the four-membered ring catalyst from methyl to phenyl, benzyl, NHBn, or pyrrolidino moieties (entries [6][7][8][9] gives serviceable albeit inferior yields of 12.Anattempt to use the triphenylphosphine oxide 7·[O] as aprecatalyst resulted in only 17 %p roduct formation (entry 10). Other commercially available CF 3 SO 2 -based reagents (sulfinate 9,s ulfonate 10,s ulfonic acid 11)p roved ineffective (entries [3][4][5].…”