Seo Woo Duck, Curtis-Long Marcus J, Ryu Young Bae, Lee Jin Hwan, Yang Min Suk, Lee Woo Song, Park Ki Hun
Division of Applied Life Science (BK 21 Program), Department of Agricultural Chemistry, Research Institute of Life Science, Gyeongsang National University, 660-701, Korea.
J Org Chem. 2006 Jun 23;71(13):5008-11. doi: 10.1021/jo060309m.
The high diastereoselectivity of the base-catalyzed epimerization of oxazolidin-2-ones 7 and 8 is shown to depend on the nature of the N-substituent (R group); when R = Bn, the 4,5-trans-product (4S,5R)-9 is formed, whereas when R = H the 4,5-cis-product (4S,5S)-10 is formed, both with >99:1 dr. The successful hydrolysis of the oxazolidin-2-one group in both cis- and trans-derivatives show this to be a stereodivergent route to enantiopure alpha-hydroxy-beta-amino isopentanoic acids (2R,3S)-1 and (2S,3S)-2.
恶唑烷 - 2 - 酮7和8的碱催化差向异构化反应具有高非对映选择性，结果表明该选择性取决于N - 取代基（R基团）的性质；当R = Bn时，会形成4,5 - 反式产物(4S,5R)-9，而当R = H时，则会形成4,5 - 顺式产物(4S,5S)-10，二者的非对映体比例均>99:1。顺式和反式衍生物中恶唑烷 - 2 - 酮基团的成功水解表明，这是一条立体发散途径，可用于制备对映体纯的α - 羟基 - β - 氨基异戊酸(2R,3S)-1和(2S,3S)-2。
