醇醛物质的量比对不饱和醛催化氢转移反应的影响

探讨了ZrO₂/SiO₂催化柠檬醛和异丙醇的氢转移反应醇醛物质的量比对反应速率的影响。结果表明,实验条件下,反应混合物的沸点随醇醛物质的量比的增大而降低;柠檬醛转化率和目标产物选择性明显受醇醛物质的量比的影响,醇醛物质的量比变化导致混合物沸点的改变可能是影响反应速率的主要因素。研究条件下,反应最适宜的醇醛物质的量比为5,表观活化能为100.5 kJ·mol^-1.     

β—突厥酮的合成-β—环柠檬醛的催化加成反应研究

突厥酮是一种名贵香料，成功合成突厥酮的关键在于合成工艺路线的选择，通过研究找到了一条反应条件温和、反应周期短，易于工业化的合成工艺路线。特别是工艺中第一步环柠檬醛的催化加成，突破了格氏反应的缺点，使反应易于操作，原料不需特殊处理，产品含量＞ ９０％ ，收率可达８５％ 以上。     

柠檬醛与苄氯制备缓释性香料的研究

研究了用柠檬醛和苄氯相转移催化合成苄基缩柠檬醛的新方法，然后用选择性还原剂NaBH4还原，获得了性能稳定的缓释性醇类香料。醛收率不低于91％，醇收率可达92．6％，产品纯度一般可在96％左右。     

D-72磺酸树脂催化柠檬醛环化合成对伞花烃

以D-72磺酸树脂为催化剂,催化柠檬醛环化反应合成对伞花烃,考察了反应介质、柠檬醛的体积分数、催化剂用量、反应温度和反应时间对柠檬醛转化率和对伞花烃产率的影响。实验结果表明,以乙酸乙酯为介质,在柠檬醛体积分数为7.5%,催化剂用量为0.4 g,70℃下反应80 min,柠檬醛的转化率为100%,对伞花烃的产率为73.65%。     

我国天然柠檬醛的利用及鸢尾酮的合成进展

我国富含柠檬醛的山苍子油资源丰富 ,每年出口约 2 0 0 0t,在世界香料市场占有特殊的地位。为了改变该资源低值单调的利用途径 ,系统地总结和评述了山苍子油半合成高档香料———鸢尾酮以及多方面综合利用的研究进展 ,阐明了将我国天然柠檬醛的资源优势转化为可持续发展的经济优势的重要意义 ,提出了以栽培种植为基础、以半合成鸢尾酮系列香料为主导、以环境友好和高效综合利用为目的的产业化模式     

Chemistry of mandibular and Dufour's gland secretions of ants in genusMyrmecocystus

Males of several species ofMyrmecocystus produce mandibular gland secretions that contain 2,4-dimethyl-2-hexenoic acid and a variety of monoterpenes that include neral, geranial, citronellol, limonene, and 2,6-dimethyl-5-hepten-1-ol. Other components identified include methyl anthranilate, octanal, octanol, octyl octanoate, and 2-hexyl-2-decenal. Methyl salicylate has been identified as a mandibular gland constituent of workers of several species in addition to mellein and monoterpenes such as cymene, limonene, and the isomers of citral. The Dufour's gland secretions of workers and females of 14 species contain typical formicine alkanes (e.g., undecane), 2-alkanols (e.g., 2-tridecanol), and 2-alkanones (e.g., 2-tridecanone). Two species in the subgenusEremnocystus produce secretions that are distinguished by the presence of significant quantities of tridecyl esters. The functions of these compounds as well as their possible chemosystematic significance in the genusMyrmecocystus are discussed.     

香料紫罗兰酮合成工艺研究

以山苍子油、柠檬草油为原料合成紫罗兰酮,研究了缩合反应、环化反应、产品精制的工艺条件;并缩合反应中,柠檬醛的转化率为99%以上,产品得率95%;环化反应中,假性紫罗兰酮的转化率98%以上,产品得率90%。产品中总含酮量95%,其中α-紫罗兰酮占80%。     

化学纯化柠檬醛方法比较

采用不同于传统纯化柠檬醛的方法,避开了化学纯化方法中使用强碱和物理方法中采用减压精馏的方式,利用索氏提取原理,在比较低的温度下(60℃),获得了高纯度的柠檬醛(98%以上)。与传统的化学纯化方法相比,柠檬醛的收率和纯度均有提高。     

减压精馏山苍子油提高柠檬醛含量的研究

研究探索了旨在提高柠檬醛含量的山苍籽油减压精馏的条件，取得了令人满意的结果。     

Synthesis of Pseudoionones by Acid and Base Solid Catalysts

The preparation of pseudoionones by aldol condensation reaction between citral and acetone have been carried out in the presence of acid (HY and beta zeolites), an acid–base (amorphous aluminophosphate) and basic catalysts such as an aluminophosphate oxynitride, MgO and different activated hydrotalcites. The results showed that acid or acid–base catalysts were not successful for performing in one pot the preparation of ionones. MgO and calcined hydrotalcites showed excellent activity and selectivity to pseudoionones, with calcined hydrotalcite more selective than MgO. Moreover, the rate of reaction can be improved by activating the hydrotalcite through rehydration. This activation can be successfully done by simply adding the optimum amount of water to the calcined hydrotalcite before reaction. The inhibiting effect of the concentration citral on the catalytic activity of rehydrated hydrotalcites that has been reported to occur at 273 K can be avoided by working at a reaction temperature of 333 K.