ORGN 530 |
| A novel protocol for the osmium-mediated aminohydroxylation reaction has been developed that employs N-sulfonyloxy carbamates as both the nitrogen source and reoxidant. This improved procedure obviates the need for chlorinating agent and stoichiometric base. The tethered aminohydroxylation (TA) reaction of allylic alcohol derivatives afforded higher yields of regioisomerically pure syn-amino alcohol products compared with the use of previously developed N-halo,N-metallocarbamate reoxidants. Homoallylic alcohol derivatives were viable substrates in the reaction, having afforded poor (<40%) product yields under the previous regime. The TA reactions could be run efficiently at lower catalyst loadings (1 mol% Os). N-Sulfonyloxy carbamate derivatives are also compatible with intermolecular aminohydroxylation reactions. Similar yields are obtainable utilising approximately half the amount of nitrogen source required with standard N-halo,N-metallocarbamates.
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New Reactions and Methodology, Heterocycles and Aromatics, Bioorganic Chemistry
8:00 PM-10:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster
Division of Organic Chemistry |
