ORGN 241 |
| Asymmetric syntheses using chiral auxiliaries on polymer support often encounter problems associated with the solid support, which means that established ‘solution-phase' reaction conditions often need extensive reoptimisation. We have developed a polymer-supported L-tyrosine derived oxazolidin-2-one that is attached to 2-chlorotrityl-chloride resin via its phenolic group. This design enables orthogonal cleavage of the oxazolidin-2-one fragment from polymer support via simple treatment with TFA, thus enabling simple characterisation of any solid-supported intermediate using conventional spectroscopic techniques. This 'cleavable linker' strategy has enabled us to rapidly optimise conditions for polymer supported asymmetric enolate alkylation reactions and apply them to the asymmetric synthesis of a library of chiral a-substituted acids and a-substituted alcohols.
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Combinatorial and Process Chemistry
8:00 AM-11:40 AM, Monday, March 26, 2007 McCormick Place East -- Room E350, Level 3, Oral
Division of Organic Chemistry |
