Cyclic bis-ureas: Applications as hosts for molecular recognition and as reliable supramolecular assembly units

ORGN 223

Linda S. Shimizu, shimizul@mail.chem.sc.edu, Department of Chemistry and Biochemistry, University of South Carolina, 631 Sumter St., Columbia, SC 29208
The Shimizu group is interested in developing homogeneous porous materials with functionalized cavities for use as confined environments for reactions. A series of bis-urea macrocycles have been synthesized from rigid spacers and urea groups. These macrocycles probe a range of different ring sizes and shapes but do not contain interior functional groups. They assembled as designed into tubular structures forming porous crystals with guest-accessible channels. The crystals can be used as a container for reactions and promoted highly stereoselective photodimerizations of alpha, beta unsaturated ketones. Recently, we have explored the feasibility of incorporating interior functional groups. New macrocycles containing pyridines and bipyridines have been synthesized that are lined with basic nitrogens. These macrocycles showed affinity for binding cations and formed metal complexes. If these functional groups are compatible with columnar self-assembly, such systems may form porous functional materials that could have applications in molecular recognition, in sensing and catalysis.
 

Young Academic Investigators
8:00 AM-12:00 PM, Monday, August 17, 2009 Walter E. Washington Convention Center -- 207A, Oral

Division of Organic Chemistry

The 238th ACS National Meeting, Washington, DC, August 16-20, 2009