ORGN 82 |
| Hydrolysis of the precursors 2a-c and 5b was shown previously to generate the oxenium ions 1a-c, that were indirectly detected by N3--trapping to yield 4. Laser flash photolysis of 2b in phosphate buffer at 266 nm generates the observable ion 1b with λmax 460 nm that decays with a lifetime of (170 ± 10) ns. This intermediate is not affected by O2, but reacts rapidly with N3- with an apparently diffusion-limited rate constant of (6.6 ± 0.2) x 109 M-1s-1. Additionally, the decay of a strong transient absorbance band observed at 360 nm is due to two unidentified intermediates with lifetimes of ca. 12 µs and 75 µs, neither of which are affected by O2 or N3-. Current research efforts are focused on the identification of these intermediates, and on the photolysis of other precursors 2a and 5b. Results of these investigations will be reported.
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Physical Organic Chemistry, Combinatorial and Process Chemistry, New Reactions and Methodology, Peptides, Proteins and Amino Acids
8:00 PM-10:00 PM, Sunday, April 6, 2008 Morial Convention Center -- Hall A, Poster
Division of Organic Chemistry |
