Shao B.
Bagdasarian AL.
Popov S.
Nelson HM.
* University of California, Los Angeles, USA
Arylation of Hydrocarbons Enabled by Organosilicon Reagents and Weakly Coordinating
Anions.
Science 2017;
355: 1403-1407
Key words
arylation - hydrocarbons - phenyl cation - silylium ion
Significance
The Nelson group reports a silylium ion catalyzed arylation of C(sp2)–H and C(sp3)–H bonds. By employing 2–5 mol% of precatalyst A in the presence of a trialkylsilane initiator, various aliphatic and aromatic hydrocarbons
were arylated with variously functionalized trimethylsilyl fluorobenzenes.
Comment
Previously, catalytic reactions involving highly reactive phenyl cation equivalents
were limited to intramolecular transformations. The authors describe the formation
of a β-silicon-stabilized phenyl cation (equivalent) II, which is proposed to subsequently undergo intermolecular insertion into the C–H
bond of a hydrocarbon present in large excess. Desilylation of the resulting Wheland
intermediate furnishes the product and regenerates the catalytically active species
I.
