ORGN 78 |
| Abstract: Controlling photocycloaddition reactions in solution to obtain a selective dimer is one of the most challenging tasks. We have overcome this challenge by orienting two reactive olefins required for photocycloaddition in a rigid and well defined confined medium such as cucurbituril. Cucurbiturils are oligomacrocycles soluble in water served as a remarkable template for conducting bimolecular reactions in high selectivity. The olefins chosen for this study are trans-1(m-pyridyl) 2-(n-pyridyl) ethylenes ( where m=n and m?n) and stilbazoles. Weak interactions such as hydrophobic, cation-? and ?-? and electrostatic interactions have been exploited to obtain remarkable selectivity during photocycloaddition studies in water. We have also compared the templating ability of less rigid hosts such as micelles with cucurbiturils. Comparison revealed that to obtain high selectivity, rigid macrocycle which can encapsulate and orient the olefins is required. A detailed study of host-guest complexation, characterization and photolysis outcome will be presented
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Process R&D, Physical Organic Chemistry, Heterocycles, Aromatics, Metal-Mediated Reactions
8:00 PM-10:00 PM, Sunday, March 25, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Organic Chemistry |
