The evaporation of fragrances with volatilities spanning over several orders of magnitude results in a shift of the olfactive impression of a perfume over time. Fixatives have repeatedly been used to slow fragrance evaporation in multiple perfumery applications. We developed a simple and reliable method to measure the evaporation kinetics of individual fragrances in a model perfume and analysed the fixative effect of 2-oxo-2-phenylacetates (α-ketoesters) on perfume evaporation. 2-Oxo-2-phenylacetates, some of which have been described as light-sensitive profragrances, are commercially available or readily prepared by esterification or transesterification of commercial starting materials. (−)-Menthyl 2-oxo-2-phenylacetate afforded single crystals that were suitable for X-ray crystal structure analysis. 2-Oxo-2-phenylacetates were found to have a fixative effect on the evaporation of fragrances with volatilities below 5000 μg L⁻¹ in fine fragrance and eau-de-toilette applications. The molecular structure of the compound rather than its molecular weight had an impact on the fixative effect to some extent.

中文翻译：

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2-氧代-2-苯基乙酸酯在高级香水和淡香水应用中的固定作用


挥发性跨越几个数量级的香料的蒸发会导致香水的嗅觉印象随着时间的推移而发生变化。在多种香水应用中，固定剂已多次被用来减缓香料的蒸发。我们开发了一种简单可靠的方法来测量模型香水中各种香料的蒸发动力学，并分析了 2-氧代-2-乙酸苯酯（α-酮酯）对香水蒸发的定香效果。 2-氧代-2-乙酸苯酯，其中一些已被描述为光敏香料前体，可商购或通过商业起始材料的酯化或酯交换容易地制备。 (−)-2-氧代-2-苯乙酸薄荷酯提供了适合 X 射线晶体结构分析的单晶。研究发现，在高级香水和淡香水应用中，2-Oxo-2-苯基乙酸酯对挥发性低于 5000 µg L ⁻¹ 的香料的蒸发具有固定作用。化合物的分子结构而不是分子量对固定效果有一定影响。