Novel class of tertiary phosphine ligands based on a phospha-adamantane framework and use in the Suzuki cross-coupling reactions of aryl halides under mild conditions.
[reaction: see text] A new class of sterically hindered phosphines based on a phospha-adamantane framework is described. Arylation or alkylation of the 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phospha-adamantane system allows for the preparation of tertiary phosphines suitable for use in palladium-catalyzed cross-coupling reactions. For example, use of a catalytic system incorporating Pd(2)(dba)(3) and 1,3,5,7-tetramethyl-2,4,8-trioxa-6-phenyl-6-phospha-adamantane is shown to promote the Suzuki cross-coupling of aryl iodides, bromides, and activated chlorides with a variety of aryl boronic acids at room temperature in a few hours with high yields.
Adjabeng
George
G
Institute of Molecular Catalysis, Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada.
Brenstrum
Tim
T
Wilson
Jeffrey
J
Frampton
Christopher
C
Robertson
Al
A
Hillhouse
John
J
McNulty
James
J
Capretta
Alfredo
A