Method for the enantioselective preparation of 3,3-diphenyl-2,3-epoxy propionic acid esters
申请人:——
公开号:US20030162982A1
公开(公告)日:2003-08-28
The invention relates to a method for the enantioselective preparation of the glycide ester (I) by (a) dihydroxylating a corresponding 3-phenyl cinnamic acid ester (II) by osmium (VIII) oxide catalysis in the presence of a Sharpless ligand and an oxidant to give a dihydroxy ester (III), (b) selectively converting the hydroxy function in the 2 position of the dihydroxy ester (III) to a leaving group, (c) intramolecularly substituting the leaving group by the hydroxy function in the 3 position to the glycide ester (I). In formulae (I), (II), and (III), R
1
represents C
1
-C
10
alkyl, aryl or arylalkyl, which can optionally be substituted, and R
2
represents C
1
-C
10
alkyl, aryl, arylalkyl, halogen, C
1
-C
10
alkoxy, acyloxy or amide, which can be optionally substituted, and n is 0 to 5.
1
本发明涉及一种手性选择性制备甘醇酯(I)的方法,包括以下步骤:(a)在Sharpless配体和氧化剂的存在下,通过钌(VIII)氧化物催化作用,使相应的3-苯基肉桂酸酯(II)二羟基化,得到二羟基酯(III);(b)选择性地将二羟基酯(III)中2位上的羟基转化为离去基团;(c)通过分子内取代反应,将3位上的羟基功能团取代为甘醇酯(I)。在式(I)、(II)和(III)中,R1代表C1-C10烷基、芳基或芳基烷基,可选地具有取代基;R2代表C1-C10烷基、芳基、芳基烷基、卤素、C1-C10烷氧基、酰氧基或酰胺基,可选地具有取代基;n为0至5.1。