摘要 |
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), R1 represents C1-C10 alkyl, aryl or arylalkyl, which can optionally be substituted, and R2 represents C1-C10 alkyl, aryl, arylalkyl, halogen, C1-C10 alkoxy, acyloxy or amide, which can be optionally substituted, and n is 0 to 5.
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