Practical method for crystalline-liquid resolution of chrysanthemic acids utilizing chiral 1,1′-binaphthol monoethyl ethers directed for process chemistry
作者:Takayuki Atago、Akihiro Tanaka、Tomoyuki Kawamura、Noritada Matsuo、Yoo Tanabe
DOI:10.1016/j.tetasy.2009.02.060
日期:2009.5
key auxiliary. Direct esterifications of 1, 2, 3, and 4 with (R)-5b gave four sets of (1R)- and (1S)-diastereomeric esters 8, 9, 6, and 7, respectively, with markedly different melting points. All of these diastereomers were easily obtained using a simple and one-step crystalline-liquid separation. The separated diastereomers 8 and 9 were easily hydrolyzed to the desired enantiopure acids 1 (>98%)
我们已经开发了一种有效的实用拆分方法,用于(1 R,3 R)-反式菊苣酸1和(1 R,3 S)-反式-2,2-二甲基-3-(2,2-二氯乙烯基)环丙烷甲酸如图2所示,基于更简单的类似物的初步结果,使用结晶-液体分离方法(无柱色谱法)(1 R)-2,2-二氯环丙烷甲酸3和(1 R -2,2-二甲基环丙烷甲酸4带有手性1,1'-联萘酚单乙醚(R)-5b作为关键辅助。的直接酯化反应1,2,3,和4与([R ) - 5b中,得到四组(1 - [R )-和(1个小号)-diastereomeric酯8,9,6,和7分别与显着不同的熔点。所有这些非对映异构体均可以通过简单的一步式结晶-液体分离方法轻松获得。分离的非对映异构体8和9容易水解为所需的对映纯酸1(> 98%)和2(> 99%),回收率分别为(R)-5b(> 90%)。