PROCESS FOR THE SYNTHESIS OF INTERMEDIATES FOR THE PREPARATION OF ASTAXANTHIN

摘要

The present invention relates to a process for the preparation of intermediates useful in the synthesis of Astaxanthin, in particular C₁₅-Wittig salts, but also 4-oxo-ß-ionones, 3-hydroxy-4-oxo-ß-ionones and the aryl esters thereof. 4-oxo-ß-ionone is prepared by starting from a ß-ionone by oxidation with bromates in the presence of iodine or iodide. 3-hydroxy-4-oxo-ß-ionone is prepared in 4 steps, starting from 4 -oxo- ß-ionone by oxidation with peracids; the aryl esters thereof are solids that are easily isolated and purified by crystallisation, and may be converted in 5 steps to C₁₅-Wittig salts and finally, by the Wittig reaction, to Astaxanthin.