New routes to 6-oxoverdazyl free radicals: Synthesis of 1,5-diisopropyl substituted verdazyls

ORGN 149

David J. R. Brook, djbrook@scu.edu1, Aaron J. Brieger, breigaj@students.udmercy.edu2, Emily Paré2, Mick Badik2, and Marie Schinke2. (1) Department of Chemistry, Santa Clara University, 500 El Camino Real, Santa Clara, CA 95053, (2) Department of Chemistry and Biochemistry, University of Detroit Mercy, 4001 W. McNichols Rd, Detroit, MI 48221
Verdazyl free radicals are stable heterocyclic free radicals with nitrogen lone pairs available for metal coordination. This feature has made them attractive candidates as building blocks for the synthesis of magnetic materials and self assembled magnetic nanostructures. There are, however, various problems associated with their synthesis and substitution patterns. Current pathways to 6-oxoverdazyls result in either methyl or aryl substituents in the 1 and 5 positions. 1,5-dimethyl verdazyls show somewhat variable stability, with some particularly interesting examples, such as the 3-(2'-pyridyl)- and 3-(2'-imidazolyl) substituted species being frustratingly fragile. Furthermore the solubility of some of these species and their coordination compounds is limited. We were interested in the introduction of alternative alkyl groups in the 1 and 5 positions, in particular to increase radical stability and solubility and also to control coordination geometry. We report the synthesis and characterization of a series of 1,5-diisopropyl substituted verdazyls via the condensation of a BOC protected hydrazine with phosgene.
 

Heterocycles, Aromatics, Materials, Devices, Switches, Combinatorial Chemistry, Metal-Mediated Reactions
8:00 PM-10:00 PM, Sunday, 13 March 2005 Convention Center -- Hall D, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, 14 March 2005 Convention Center -- Sails Pavilion, Sci-Mix

Division of Organic Chemistry

The 229th ACS National Meeting, in San Diego, CA, March 13-17, 2005