A Simple Method for Resolution of <i>Endo</i>
-/<i>Exo</i>
-Monoesters of <i>Trans</i>
-Norborn-5-Ene-2,3-Dicarboxylic Acids Into Their Enantiomers
作者:Vitaly N. Kovalenko、Yurii Yu. Kozyrkov
DOI:10.1002/chir.22404
日期:2015.2
obtainable from trans‐norborn‐5‐ene‐2,3‐dicarboxylic acid methyl and tert‐butyl monoesters was performed by crystallization of the respective salts prepared with (R)‐ and (S)‐1‐phenylethylamine. Starting from racemic endo‐monomethyl ester of trans‐norborn‐5‐ene‐2,3‐dicarboxylic acid, prepared by partial hydrolysis of the cyclopentadiene‐dimethyl fumarate adduct, the corresponding (2R,3R)‐endo‐monoester was
通过用(R)-和(S)-1-苯基乙胺制备的相应盐进行结晶,可以分离可从反式降冰片烯5烯2,3-二羧酸甲酯和叔丁基单酯获得的旋光异构体。从外消旋起始内切-单甲基酯反-norborn -5-烯-2,3-二羧酸,由环戊二烯富马酸二甲酯加合物的部分水解,相应的(2制备- [R,3 - [R )-内切-monoester分离在四氯甲烷中反复结晶七次后,其对映体过量(ee)产率为97%。从exo- mono-开始叔丁基相同的酸,由环戊二烯的马来酸酐加合物的醇解制备的酯,随后异构化,(2 - [R,3 - [R )-外型-monoester物后从乙醇中4个重复结晶分离出> 98%ee的产率。从含有(S)-1-苯乙胺的母液中结晶出酸,生成的产物具有相反的立体化学构型。手性27:151–155,2015。©2014 Wiley Periodicals,Inc.