Controlled Release of Perfumery Aldehydes and Ketones by Norrish Type-II Photofragmentation of -Keto Esters in Undegassed Solution
作者:Sabine Rochat、Caroline Minardi、Jean-Yves de Saint Laumer、Andreas Herrmann
DOI:10.1002/1522-2675(20000705)83:7<1645::aid-hlca1645>3.0.co;2-s
日期:2000.7.5
Alkyl or aryl α-keto esters of primary or secondary alcohols decompose upon irradiation at 350 – 370 nm from the intermediate triplet state into aldehydes or ketones in polar, as well as apolar solvents. The use of these keto esters as delivery systems for the controlled release of perfumery aldehydes and ketones was investigated by photoirradiation in the presence of oxygen with a Xe or UV lamp, as
伯醇或仲醇的烷基或芳基 α-酮酯在 350 – 370 nm 的辐照下从中间三重态分解为极性和非极性溶剂中的醛或酮。通过在氧气存在下使用氙灯或紫外线灯以及户外阳光进行光辐照,研究了这些酮酯作为控制释放香料醛和酮的释放系统的用途。辐照溶液的系统 GC/MS 分析表明,在这些条件下,酯侧链的所需 Norrish II 型断裂是大多数情况下的主要反应途径。从烷基酮酯的烷基侧链中提取 γ-H,以及分子内Paterno-Buchi 反应或不同香茅基α-酮酯中烯烃官能团的环氧化被确定为最重要的副反应。一些实验结果已经在从头算和密度泛函计算的基础上进行了合理化。发现(环己基)氧代乙酸酯和氧代(苯基)乙酸酯是所需香料应用的最合适的前体。