Pd-PEPPSI-IPent: an active, sterically demanding cross-coupling catalyst and its application in the synthesis of tetra-ortho-substituted biaryls.
Incredible Bulk: A series of N-heterocyclic carbene catalysts (see picture) were prepared and evaluated in the Suzuki-Miyaura reaction. A variety of sterically encumbered tetra-ortho-substituted biaryl products were formed from unreactive aryl chlorides using the isopentyl-substituted catalyst at temperatures ranging from 65 degrees C to room temperature. The cyclopentyl-substituted catalyst was virtually inactive, demonstrating that "flexible bulk" is essential to promote these transformations.
Organ
Michael G
MG
Department of Chemistry, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada.
Calimsiz
Selçuk
S
Sayah
Mahmoud
M
Hoi
Ka Hou
KH
Lough
Alan J
AJ