Anti-Selective Epoxidation of Methyl α-Methylene-β-tert-butyldimethylsilyloxycarboxylate Esters. Evidence for Stereospecific Oxygen Atom Transfer in a Nucleophilic Epoxidation Process
| Autor: | Jakub Svenda, Andrew G. Myers |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
Molecular Structure
Chemistry Stereochemistry Potassium Organic Chemistry chemistry.chemical_element Esters Stereoisomerism Biochemistry Catalysis Article chemistry.chemical_compound Stereospecificity Nucleophile Deuterium Epoxy Compounds Molecule Organosilicon Compounds Physical and Theoretical Chemistry Methylene Oxidation-Reduction |
| Zdroj: | Organic Letters. 11:2437-2440 |
| ISSN: | 1523-7052 1523-7060 |
| DOI: | 10.1021/ol900665a |
| Popis: | Methyl alpha-methylene-beta-tert-butyldimethylsilyloxycarboxylate esters are found to undergo diastereoselective epoxidation in the presence of potassium tert-butoxide-tert-butyl hydroperoxide to form anti products. In an effort to better understand mechanistic details of the transformation and the basis of diastereoselectivities observed, we studied the epoxidation of substrates with alpha-methylene groups containing (trans) deuterium labels and discovered that oxygen-atom transfer proceeds with > or = 95% stereospecificity in all cases examined. These and other experiments suggest that the mechanism of epoxidation is not distinguishable from a concerted process. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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