| abstract |
The invention relates to a process for the preparation of polyene compounds, which consists in that a racemic or optically active diol of the formula halogenated and the halide obtained is reacted with a triarylphosphine, and if desired the phosphonium salt of the general formula obtained in which X denotes an aryl radical and Y halogen, with the dialdehyde of the formula condensed to racemic or optically active astaxanthin, and starting materials therefor, and intermediates in this process. |