ORGN 718 |
| Asymmetric autoinduction has been observed in the reaction of acrolein with dimethyl phosphite using titanium(IV) isopropoxide/dimethyl tartrate (DMT) complex as catalyst. The conversion and product enantiomeric excess for the reaction were determined on a series of aliquots using 31P NMR spectroscopy. A plot of the enantiomeric excess (e.e.) vs. conversion gives a logarithmic curve reaching a terminal e.e. of 70%. This suggests that the product of the reaction incorporates itself into the catalyst and generates a more stereoselective catalyst in solution. Exploiting this effect could lead to products which have enantiomeric excesses of >99%. Adding product to the reaction does not give an increase in the terminal ee but does give a rate increase as the reaction completes in only 2 hours compared to the undoped reaction which requires 15-24 hours.
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Asymmetric Reactions, Combinatorial Chemistry, Molecular Recognition and Self-Assembly, Proteins, Peptides, Amino Acids and Enzyme Inhibitors
8:00 PM-10:00 PM, Wednesday, March 28, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Organic Chemistry |
