The transesterification-dehydration of lactone I (of 1, 1, 6, 10-tetramethyl-6-hydroxy-decalyl-5-acetic acid) yields besides small quantities of isolactone II the ester of the corresponding non saturated acid III. Prolonged heating in the presence of more concentrated sulfuric acid isomerizes this acid into acid IV. If the concentration of the latter reaches 45%, saponification of the reaction products
内酯I(1、1、6、10-四甲基-6-羟基-癸基-5-
乙酸的酯基)的酯交换脱
水反应除了少量异内酯II以外,还产生了相应的非饱和酸III的酯。在更浓的
硫酸存在下长时间加热会使该酸异构化为酸IV,如果后者的浓度达到45%,则反应产物的皂化作用不会再产生III mp 118°或IV mp 102°的酸,而是低共熔酸。 mp 84°。讨论了相应的红外光谱。