Blakey SB,
MacMillan DW. C.
*
California Institute of Technology, Pasadena, USA
The First Suzuki Cross-Couplings of Aryltrimethylammonium Salts.
J. Am. Chem. Soc. 2003;
125: 6046-6047
DOI:
10.1021/ja034908b
Key words
nickel catalysis - Suzuki cross-coupling - trialkylammonium salts
Significance
Transition-metal-catalyzed cross-coupling reactions continue to represent a route
for C–C bond formation. In 2003, MacMillan and Blakey reported the Suzuki cross-coupling
reaction of aryltrimethylammonium triflates. During their investigations, authors
found that while palladium catalysts were unsuccessful for the coupling, the use of
an NHC-Ni(0) complex successfully catalyzed the transformation. This report represented
the first catalyst system that was efficient in activating aryl-ammonium bonds.
Comment
The reaction generated products with yields ranging from 82–98%. The authors included
examples using electron-rich ammonium salts, typically less susceptible to oxidative
addition, and various electronically and sterically different arylboronic acids and
esters. The use of trialkylammonium triflates continue serve as valuable coupling
partners in many cross-coupling reactions.
