Development of the suzuki-miyaura cross-coupling reaction: use of air-stable potassium alkynyltrifluoroborates in aryl alkynylations.
The palladium-catalyzed cross-coupling reaction of potassium alkynyltrifluoroborates with aryl halides or triflates proceeds readily with moderate to excellent yields. The potassium alkynyltrifluoroborates are air- and moisture-stable crystalline solids that can be stored indefinitely, which will provide an advantage in applications to combinatorial chemistry. The alkynyl cross-coupling reaction can be effected using 9 mol % of PdCl2(dppf).CH2Cl2 as catalyst in THF or THF-H2O in the presence of Cs2CO3 as the inorganic base. A variety of functional groups are tolerated in both partners.
Molander
Gary A
GA
Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA. gmolandr@sas.upenn.edu
Katona
Bryson W
BW
Machrouhi
Fouzia
F