On the mechanism of dirhodium(II) caprolactamate oxidations: A novel multivalent dirhodium complex catalyzes oxidation using tert-butyl hydroperoxide with uncharacteristic reactivity and selectivity

ORGN 362

Jason M. Nichols, jnicholz@umd.edu, Arthur J. Catino, acatino@umd.edu, and Michael P. Doyle, mdoyle3@umd.edu. Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742
Dirhodium(II) caprolactamate catalyzes allylic oxidation using tert butyl hydroperoxide (TBHP) as the terminal oxidant. This highly successful protocol was recently extended to benzylic substrates. Current explorations into the role of the higher valent dirhodium species as an oxidant reveal that the products of TBHP disproportionation are not the principle H atom abstraction moieties. A mixed-valent dirhodium species is determined to be a single electron oxidant that demonstrates remarkable selectivity between electronically and sterically dissimilar substrates. The oxidation reaction displays a sensitivity to base strength and a novel dirhodium(II) complex is implicated as a H atom abstraction catalyst.

Bioorganic, Metal-Mediated Reactions, and Molecular Recognition
8:00 PM-10:00 PM, Tuesday, 30 August 2005 Washington DC Convention Center -- Hall A, Poster

8:00 PM-10:00 PM, Monday, 29 August 2005 Washington DC Convention Center -- Hall A, Sci-Mix

Division of Organic Chemistry

The 230th ACS National Meeting, in Washington, DC, Aug 28-Sept 1, 2005