A process for the preparation of a 4-acyloxy-2-methyl-crotonaldehyde of the formula ##STR1## where R is hydrogen or an aliphatic radical of 1 to 5 carbon atoms, by reacting a 1,1,4-triacyloxy-2-methyl-but-2-ene of the formula ##STR2## where R.sup.1 and R.sup.2 are each hydrogen or an aliphatic radical of 1 to 5 carbon atoms, with water in the presence of a carboxylic acid of the formula R--COOH III.
一种制备式为##STR1##的4-酰氧基-2-甲基-鲁托烯醛的方法,其中R是氢或1至5个碳原子的脂肪基,通过在酸的存在下将式为##STR2##的1,1,4-三酰氧基-2-甲基-丁-2-烯与
水反应。其中R1和R2是氢或1至5个碳原子的脂肪基。