Oxidation with ozone of
3,7-dimethyloctyl acetate (7) adsorbed on silica gel, alumina or barium
sulphate proceeds in good yield and affords mainly the 7-hydroxy compound (8)
and the 7-nor-ketone (9). Minor products include the 3-alcohol (10) and the
3,7-diol (11). The reaction involves interaction of gaseous ozone with the
adsorbed organic substrate. The relative yields of the various products are
related to the substrate loading. The results show that the very high
regioselectivity exhibited by the reaction when conducted under suitable
experimental conditions may be attributed to the mutual steric effect of one
molecule upon the other in the adsorbed monolayer.
用臭氧氧化
用臭氧氧化吸附在硅胶、氧化铝或硫酸钡上的 3,7-二甲基辛基乙酸酯 (7)
在硅胶、氧化铝或硫酸钡上吸附的 3,7-二甲基乙酸乙酯(7)经臭氧氧化后,产量很高,主要生成 7-羟基化合物(8
和 7-正酮(9)。次要产物包括 3-醇(10)和
3,7-二醇 (11)。反应涉及气态臭氧与吸附的有机底物之间的相互作用。
吸附的有机底物相互作用。各种产物的相对产量
与底物负载有关。结果表明
在合适的实验条件下进行时,该反应表现出极高的区域选择性。
实验条件下,反应表现出极高的区域选择性,这可能是由于在单质分子中一个分子对另一个分子的相互立体效应
分子对吸附单层中另一分子的相互立体效应。