| abstract |
The present invention relates to a new method of condensing polyenic compounds wherein a compound having the formula III <IMAGE> (III) is condensed with a compound having the formula IV <IMAGE> (IV) under the influence of a Lewis acid or a protic acid. R1 through R7 represent alkyl or alkenyl groups, A' is preferably chlorine, B is preferably a hydroxyl group, and n' is 0 to 10. The invention also relates to novel intermediates for use in the preparation of Vitamins A and E produced by means of the new method. |