Asymmetric Synthesis by the Intramolecular Haloetherification Reaction of Ene Acetal: Discrimination of Prochiral Dienes in Cyclohexane Systems
作者:Hiromichi Fujioka、Naoyuki Kotoku、Yoshinari Sawama、Hidetoshi Kitagawa、Yusuke Ohba、Tsung-Lung Wang、Yasushi Nagatomi、Yasuyuki Kita
DOI:10.1248/cpb.53.952
日期:——
A novel asymmetric synthesis of the cyclohexane derivative functionalized by some substituents has been developed from the diene acetals (1), prepared from the corresponding diene aldehyde and (+)-hydrobenzoin. The treatment of 1 with NBS in the presence of MeOCH2CH2OH predominantly afforded 2 in a stereoselective manner. Subsequent alkylation of the methoxyethoxy group produced the optically active
由由相应的二烯醛和(+)-氢安息香素制备的二烯缩醛(1)已经开发出一种新的不对称合成被某些取代基官能化的环己烷衍生物的方法。在MeOCH2CH2OH存在下用NBS处理1主要以立体选择的方式得到2。随后甲氧基乙氧基的烷基化以良好的产率产生了光学活性的环己烯化合物(3)。3中剩余烯烃的立体选择性化学修饰是通过OsO4-氧化进行的。