ORGN 271 |
| Since the pioneering work of Dolling et al. in 1984, asymmetric synthesis by chiral phase transfer catalysis has provided an attractive method of preparing various optically active compounds. However, most of the elaborated chiral phase transfer catalysts reported so far have been restricted to cinchona alkaloid derivatives, which unfortunately constitutes a major difficulty in rationally designing and fine-tuning of catalysts to attain sufficient reactivity and selectivity for various asymmetric transformations. Accordingly, a series of structurally rigid, chiral binaphthyl- or biphenyl-modified quaternary ammonium salts derived from chiral binaphthol or biphenols have been newly prepared as simple, yet very active chiral phase transfer catalysts, and successfully applied to the catalytic enantioselective alkylation of tert-butyl glycinate-benzophenone and tert-butyl alaninate-p-chlorobenzaldehyde Schiff base under mild conditions for practical asymmetric synthesis of alpha-alkylamino and alpha,alpha-dialkylamino acids. |
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Asymmetric Syntheis of α-Amino Acids: Novel Developments and Future Directions
1:00 PM-5:40 PM, Monday, March 26, 2007 McCormick Place Lakeside -- Room E350, Level 3, Oral
Division of Organic Chemistry |