转自：康龙化成

Iron-Mediated Nitrate Reduction at Ambient Temperature for Deaminative Sulfonylation and Fluorination of Anilines

Tim Schulte,‡ Deepak Behera,‡ Davide Carboni, Annika Höppner, Felix Waldbach, Javier Mateos, Ahmet Altun, Markus Leutzsch, Moritz L. Krebs, and Tobias Ritter*

Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr 45470, Germany;

Institute of Organic Chemistry,RWIH Aachen University Aachen 52074,Germany;

—JACS., 2025, DOI: 10.1021/jacs.4c17981

Recommended by Qilin Li_PDM

KEY WORDS: 

Deamination,Sulfonylation, Fluorination (反应类型) , Anilines (原料), arylsulfonic acids,aryl sulfonic amide, Aryl fluoride (产物), C(sp2)−S, C(sp2)− F(成键类型), Fe(NO3)3, Na2S2O3, fleeting intermediate (其他)

ABSTRACT:Preparation of arylsulfonic acids and derivatives can be achieved under mild conditions from aryldiazonium salts, although conventional methods often require isolation or accumulation of these potentially hazardous intermediates. Herein, we present that iron nitrate reduction at 25℃ enables thein situ generation of diazonium salts, which allows direct deaminative chlorosulfonylation and fluorination from anilines via aryldiazonium salts as fleeting intermediates. Other sulfonic acid derivatives, such as sulfonamides, sulfonyl fluorides, and sulfonic acids, are readily accessible from this method.

Background and this work

Aniline scope for deaminative chlorosulfonylation (selected)

Aniline scope for the direct deaminative fluorination

Aniline scope for direct deaminativesulfonic acid synthesis

ProposedMechanism

In conclusion, Prof. Tobias Ritter and coworkers have demonstrated that inexpensive Fe(NO3)3·9H2O can generate NO2 through nitrate reduction with thiosulfateat room temperature (25℃), which enables the use of the nitrate reduction strategy for the in situgeneration of aryl diazonium salts below 85℃. The iron nitrate reduction was utilized for the deaminative chlorosulfonylation of a variety of structurally and electronically diverse anilines and amino heterocycles, giving access to multiple sulfur-based functional groups directly from the corresponding aromatic amines, without accumulation of the respective diazonium salt. The deaminative fluorination was presented as an additional application of Fe-mediated nitrate reduction. The iron nitrate reduction will also enable other deaminative functionalization reactions that require close to ambient temperature. Additionally, a deaminative sulfonic acid synthesis directly from anilines as a previously unknown transformation is described.

（转自：康龙化成）