ORGN 136 |
Enantioselective organic transformations via organoaluminum catalysis
| Christopher R. Graves and SonBinh T. Nguyen. Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 |
| The catalytic Meerwein-Schmidt-Ponndorf-Verley (MSPV) reduction (A) of carbonyls to their respective alcohols was investigated. The mechanistic pathway of the MSPV reduction was studied both computationally and experimentally to ascertain a previously proposed direct hydrogen transfer mechanism. Strong correlation between theoretical calculations and experimental values of the activation energy and kH/kD support the direct mechanism over other possible pathways. Reaction rate and asymmetric consequences of ligand incorporation were investigated to find both a highly reactive and selective MSPV catalyst system. Several vaulted atropic ligands, varying in overall structure, substitution, and heteroatom incorporation, were studied. It was shown that while other ligands dramatically accelerated the rate of reduction (10–100 fold), the selectivity of the reaction was decreased as compared to the 2,2'-dihydroxy-1,1'-biphenyl (BINOL)/AlMe3 system. The BINOL/AlMe3 system was applied to other Lewis acid mediated organic transformations, including the Oppenauer oxidation (B), tandeum Micheal/MSPV reactions (C), Claisen rearrangements (D), and Aldol reactions (E). 
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Asymmetric Reactions and Syntheses, Metal-Mediated Reactions, Materials, Molecular Recognition
8:00 PM-10:00 PM, Sunday, August 22, 2004 Pennsylvania Convention Center -- Hall D, Poster
Division of Organic Chemistry
The 228th ACS National Meeting, in Philadelphia, PA, August 22-26, 2004
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