Department of Chemistry, National Taiwan Normal University , Taipei 11677, Taiwan.
Org Lett. 2015 Feb 6;17(3):430-3. doi: 10.1021/ol5033656. Epub 2015 Jan 8.
An organocatalytic kinetic resolution of racemic secondary nitroallylic alcohols via Michael/acetalization sequence to give fully substituted tetrahydropyranols is described. The process affords the products with high to excellent stereoselectivities (up to 19.9:1.5:1 dr and 98% ee). The highly enantioenriched, less reactive (S)-nitroallylic alcohols 3 were isolated with good to high chemical yields (30-44%). The synthetic application of the resolved substrate is shown toward the synthesis of enantioenriched (+)-(2S,3R)-3-amino-2-hydroxy-4-phenylbutyric acid.
通过迈克尔/缩醛化序列对消旋仲硝基烯丙醇进行有机催化动力学拆分，以得到完全取代的四氢吡喃醇。该过程以高至优异的立体选择性（高达 19.9:1.5:1dr 和 98%ee）得到产物。高对映体富集、反应性较低的（S）-硝基烯丙醇 3 以良好至高的化学收率（30-44%）被分离出来。拆分底物的合成应用表明，其可用于合成对映体富集的（+）-（2S,3R）-3-氨基-2-羟基-4-苯基丁酸。
