A process for the manufacture of polyene esters or polyene acids comprises reacting a polyene O,O-dialkylacetal of di(O,O-dialkylacetal) with a vinylketene acetal or analogue thereof in the presence of a Lewis acid, hydrolyzing the reaction mixture depending on the vinylketene acetal used, subsequently cleaving alcohol under strongly basic conditions from the polyene derivative produced at this stage and, where the desired ester or carboxy group is still not present, performing the respective conversion. Certain intermediates in this process form a further aspect of the invention. The final products are primarily carotenoids which can be used appropriately, e.g. as colorants and pigments for foodstuffs, animal products etc.
一种用于生产聚烯酯或聚烯酸的方法包括将聚烯O,O-二烷基
乙缩醛与
乙烯基甲酮
乙缩醛或其类似物在Lewis酸的存在下反应,根据所使用的
乙烯基甲酮
乙缩醛的不同,对反应混合物进行
水解,随后在强碱条件下从这一阶段产生的聚烯衍
生物中裂解醇,并在所需的酯或羧基仍不存在的情况下,进行相应的转化。该过程中的一些中间体构成了发明的另一个方面。最终产品主要是类
胡萝卜素,可以适当使用,例如作为食品、动物产品等的
着色剂和
颜料。