ORGN 124 |
| Development of highly selective methods for photochemical organic synthesis, driven by a heterogeneous catalyst, is one of the biggest challenges in chemistry. Much investigation has been made based on systems using a semiconductor, titanium dioxide; however, oxidation of substrates by hydroxyl radical is nonselective, resulting in insufficient product selectivity. Herein, we report that titanium dioxide with a mesoporous structure, when photoactivated in water, demonstrates an unprecedented photocatalytic activity, driven strongly by an adsorption degree of molecules onto the catalyst surface. This promotes a preferential conversion of well-adsorbed molecule. We highlight a successful application of this unusual catalytic property to selective transformation of a well-adsorbed molecule into a less-adsorbed molecule, labeled as "stick-and-leave" transformation, which enables a transformation of benzene into phenol, one of the most difficult synthetic reactions, with very high selectivity (>80%). |
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Asymmetric Reactions and Syntheses, Physical Organic Chemistry, Combinatorial Chemistry, Total Synthesis
8:00 PM-10:00 PM, Sunday, 26 March 2006 Georgia World Congress Center -- Ex. Hall B4, Poster
Division of Organic Chemistry |