The invention relates to a process for preparing phytofluene of the formula I,
where
a) a phosphonium salt of the formula II is condensed with an aldehyde of the formula III
in a Wittig reaction to give an acetal of the formula IV
b) the condensation product of the formula IV is subjected to an acid-catalyzed acetal hydrolysis to give the aldehyde of the formula V
c) and V is condensed in a further Wittig reaction with a phosphonium salt of the formula VI to give phytofluene
where the radicals R
1
, R
2
and R
7
, and X
−
and Y
−
have the meaning sated in the description.
本发明涉及一种制备式I的植物类
胡萝卜素的过程,其中a)式II的
磷酸盐与式III的醛在威廉逊反应中缩合,得到式IV的
缩醛;b)式IV的
缩醛经过酸催化的
缩醛水解反应,得到式V的醛;c)将V的醛与式VI的
磷酸盐在进一步的威廉逊反应中缩合,得到植物类
胡萝卜素,其中基团R1、R2和R7,以及X-和Y-的含义如描述中所述。