Categories: C-S Bond Formation >
Synthesis of sulfonamides
The bench-stable colorless solid charge-transfer complex generated from the combination of DABCO and sulfur dioxide, DABSO, can replace gaseous sulfur dioxide in organic synthesis. Reactions with Grignard reagents form sulfinates, which can then be converted in situ to sulfonamides. Alternatively, reaction with anilines and iodine leads to the formation of a series of sulfamides.
H. Woolven, C. Gonzáles-Rodríguez, I. Marco, A. L. Thompson, M. C. Willis, Org. Lett., 2011, 13, 4876-4878.
A simple copper-catalyzed aminosulfonylation of aryldiazonium tetrafluoroborates, DABCO·(SO2)2, and N-chloroamines provides a wide range of sulfonamides in good yields under mild conditions. Mechanistic investigation suggests that a radical process and transition-metal catalysis take place.
F. Zhang, D. Zheng, L. Lai, J. Cheng, J. Sun, J. Wu, Org. Lett., 2018, 20, 1167-1170.
A Pd-catalyzed coupling of aryl iodides and the sulfur dioxide surrogate DABSO provides aryl ammonium sulfinates, that can be transformed in a one-pot process to various functionalized sulfonamides by simple treatment with an aqueous solution of the relevant amine and sodium hypochlorite (bleach). A broad range of amines, including anilines, and amino acid derivatives can be used.
E. F. Flegeau, J. M. Harrison, M. C. Willis, Synlett, 2016, 27, 101-105.
A one-pot three-component reaction involving nitroarenes, (hetero)arylboronic acids, and potassium pyrosulfite provides a broad range of sulfonamides bearing different reactive functional groups in very good yields through sequential C-S and S-N coupling.
K. Chen, W. Chen, B. Han, W. Chen, M. Liu, H. Wu, Org. Lett., 2020, 22, 1841-1845.
Sulfamoyl chlorides can be easily activated by Cl-atom abstraction in the presence of a silyl radical. This mode of activation can be used for a single-step hydrosulfamoylation using inexpensive olefins, tris(trimethylsilyl)silane, and photocatalyst Eosin Y.
S. M. Hell, C. F. Meyer, G. Laudadio, A. Misale, M. C. Willis, T. Noël, A. A. Trabanco, V. Gouverneur, J. Am. Chem. Soc., 2020, 142, 720-725.
A practical photoredox-catalyzed generation of sulfamyl radicals followed by radical sulfonamidation of enol silyl ether provides functionalized β-ketosulfonamides in good yields under mild conditions.
Q. Luo, R. Mao, Y. Zhu, Y. Wang, J. Org. Chem., 2019, 84, 13897-13907.