Catalytic Transformations of Sulfonium Salts via C‐S Bond Activation

Abstract

After the 20‐year dormant period since Liebeskind's seminal report, triorganosulfonium salts have now proved to be reliably useful surrogates of or complement to organic halides in a variety of transition‐metal‐catalyzed transformations. By necessity, my group developed Suzuki‐Miyaura ring‐opening arylation of sulfonium salts of dibenzothiophenes with tetraarylborates and Pd‐catalyzed intramolecular C−H/C−S coupling. Following this starting point and experiencing the decent reactivity of sulfonium salts, in order to maximize the synthetic utility of organosulfur compounds, we successfully applied readily available sulfonium salts to Ni‐catalyzed coupling with arylzinc reagents, Pd‐ or photoredox‐catalyzed Mizoroki‐Heck reaction, Pd‐catalyzed alkoxycarbonylation, Pd‐catalyzed Miyaura borylation, Ni‐catalyzed reductive carboxylation, and Ni‐catalyzed zincation. I sincerely hope this Personal Account will facilitate further development of reactions of triorganosulfonium salts which are difficult to achieve using conventional organic (pseudo)halides.

High Site Selectivity in Electrophilic Aromatic Substitutions: Mechanism of C–H Thianthrenation

“…In parallel, the groups of Procter and Alcarazo have reported the use of dibenzothiophene S -oxide ( DBTO ) to access the corresponding sulfonium salts ( Ar–DBT + ). , With the aim of introducing 18 F via nucleophlic substitution, we have also used Ar–DBT + salts as linchpins, finding site selectivities somewhat lower than those observed for Ar–TT + in their preparation from arenes (>50:1 in ethylbenzene). While the synthetic utility of aryl sulfonium salts is currently well recognized, − the reasons behind the high selectivity on their formation from arenes still remain largely unexplored and are not well understood.…”

Photoinduced aerobic C–S borylation of aryl sulfides

“…[15][16][17][18][19][20] In addition, preactivation strategies are also employed by transforming aryl sulfides to activated aryl sulfonium salts. 21,22 Owing to the importance of organoboron compounds, particularly aryl boronate esters, in organic chemistry, 23 great efforts have been devoted to the formation of aromatic C-B bonds. Pioneered by the Miyaura borylation reaction, various C-heteroatom borylations have been developed by using the corresponding aromatic electrophiles including aryl sulfides.…”

Depolymerization of robust polyetheretherketone to regenerate monomer units using sulfur reagents

“…Sulfur can be introduced into various organic compounds, and the sulfur functional group can be converted into sulfonium salts as useful eliminating groups. 28,29 Using a transition metal catalyst, both the sulfonium group and original sulfur functional group can be used as leaving groups to form new bonds. 30 Therefore, if super engineering plastics can be depolymerized and functionalized using sulfur reactants, the prevailing problem can be solved.…”