Bifunctional Catalysts for C—H Bond Conversion Travis J. Williams, Loker Hydrocarbon Research Institute University of Southern California Bifunctional catalysts offer excellent potential for designing reactivity and selectivity into two separate parts of a molecular scaffold. For example, one could design a bifunctional catalyst in which one combines a C-H bond activation system with a coordinating group that can direct the catalyst to particular C-H bonds. We have recently applied this H O Ph O H (Ph C O)Fe(CO) O O 4 4 3 concept to the development of an H Ph Ph iron(0)-based oxidation catalyst acetone, 79% Ph Fe H MeO MeO that exploits a proton to direct OC hydride abstraction from alcohols. CO We are currently developing a two-metal boron-ruthenium system to enable us to extend this concept to general C-H groups. In this model the boron will coordinate a lone pair in the C-H activation target and the ruthenium will affect hydride abstraction from a neighboring C-H group. Oxidation by this mechanism has homology to a C-H agostic complex that we have recently characterized. We are currently working with a hydroxide-bridged bimetallic complex that is convenient pre-catalyst for C-H oxidation reactions. H3C B
HH C H
N N
Ru
H3C B
R O B HO N
H N N
Ru
N
Ru N N
An agostic boron methyl
Hydride abstraction from an ether
= N
