Rapid Interception of C_nF_2n+1(O)SO^. Radical with Copper‐Based Carbene: A Novel Access to Perfluoroalkanesulfinate Ester

Abstract

In this communication, an unprecedented interception of CnF2n+1(O)SO. radical with a copper‐based carbene has been established. Distinguished by wide substrate scopes and mild reaction conditions, this novel radical–carbene coupling reaction (RCC reaction) provides a fundamentally different and mechanistically interesting strategy for the synthesis of perfluoroalkanesulfinate esters.

(Fluoromethylsulfonyl)methylation of Quinoxalinones Using NaSO2CH2F for C–F Bond Cleavage

“…Furthermore, introduction of the fluoromethylsufinate group typically involves the construction of a S-CH 2 F group, which is then oxidized again. There are fewer examples of the direct introduction of sulfonyl-fluoromethyl groups . In particular, the use of NaSO 2 CH 2 F as the methylene source has not been fully investigated.…”

“…On the basis of the aforementioned observations and related reports, the detailed mechanism of our proposed transformation is outlined in Scheme . Initially, the monofluoroalkylsulfinate radical ( A ) is generated from NaSO 2 CH 2 F via a single electron transferred by the AgNO 3 /K 2 S 2 O 8 system. , Then, the CH 2 F radical, generated via the release of SO 2 by the SO 2 CH 2 F radical, reacts with quinoxalinone upon its addition to the most electrophilic C 3 position. Subsequently, intermediate A undergoes a 1,2-hydrogen shift to give carbon radical intermediate B .…”

Synthesis of Difluoromethanesulfinate Esters by the Difluoromethanesulfinylation of Alcohols

“…In the presence of HCF 2 SO 2 Na and Ph 2 P­(O)­Cl, a wide variety of alcohols 1 , including primary, secondary, and tertiary alcohols, are efficiently converted to the corresponding difluoromethanesulfinate esters 2 (R-OS­(O)­CF 2 H) at room temperature in good to excellent yields (Figure b). Although trifluoromethanesulfinate esters (R-OS­(O)­CF 3 ) , and difluoromethanesulfonate esters (R-OS­(O) 2 CF 2 H) ,,, have been previously reported, to the best of our knowledge, this is the first example of the synthesis of difluoromethanesulfinate esters. The mechanistic details of this transformation are revealed by NMR and LC-MS analyses of the reaction mixtures.…”