共查询到19条相似文献,搜索用时 93 毫秒
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在对甲基苯磺酸的催化下,利用微波辐射技术,在常压下快速合成了香料糠酸正丁酯。最佳反应条件为:醇酸物质的量比为3.5∶1,催化剂0.70g,带水剂5mL,辐射时间10min,微波功率700W,转化率达95.3%。 相似文献
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微波法快速合成香料糠酸正丁酯 总被引:1,自引:0,他引:1
在对甲基苯磺酸的催化下,利用微波辐射技术,在常压下快速合成了香料糠酸正丁酯。最佳反应条件为:醇酸物质的量比为3.5∶1,催化剂0.70g,带水剂5mL,辐射时间10min,微波功率700W,转化率达95.3%。 相似文献
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糠醛歧化得到糠酸,以糠酸和异戊醇为原料,浓硫酸催化合成了糠酸异戊酯,运用正交方法考察了糠酸用量、异戊醇用量、催化剂用量、反应时间等因素对糠酸异戊酯产率的影响,得到了最佳条件。 相似文献
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以硫酸氢钠为催化剂,环己烷为带水剂,异丁酸和苯氧乙醇为原料,合成了食用香料异丁酸苯氧乙酯。考察了催化剂种类、原料摩尔比、带水剂用量、反应时间、催化剂的量对产率的影响。实验表明,较优的反应条件为:苯氧乙醇与异丁酸的摩尔比为0.20:0.10,催化剂硫酸氢钠为0.005mol,环己烷20mL,反应2.5h,产率为94.2%,采用红外光谱和气-质联用等分析手段对产物进行了结构确定。 相似文献
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以环已酮和巯基乙醇为原料,采用TiSiW12O40/TiO2作催化剂,合成了一种新的香料化合物1,4-氧硫杂螺[4,5]癸烷,并用元素分析、IR、^1H NMR对其结构进行了表征。结果表明,n(环己酮)与n(巯基乙醇)的比为1.0;1.3,催化剂负载量ω(TiSiW12O40)为18%,m(催化剂)与m(环己酮)的比0.06:1,反应时间4h,目标产物的收率为90.7%。催化剂无需处理可直接重复使用8次以上。 相似文献
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The solubilisation of three perfumes has been studied in monoethanolamine lauryl sulphate and sodium lauryl ether sulphate solutions. The effect of the addition of nonionic surfactants have also been followed. A method is described for the olfactive examination of the solutions and results are given for its application to certain of the systems. 相似文献
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冰醋酸和正丙醇在磷钨酸镧的催化作用下,合成香料乙酸正丙酯.考察了反应温度、冰醋酸与正丙醇的摩尔比、催化剂用量及反应时间对酯收率的影响.结果表明,用磷钨酸镧催化合成乙酸正内酯的最佳工艺条件为反应温度为100℃,冰醋酸与正丙醇的摩尔比为1.2∶1.0,催化剂的质量为2.5g,反应时间为2.5h.在最佳反应条件下,酯收率为78%. 相似文献
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J. M. BLAKEWAY M. L. FREY S. LACROIX M. S. SALERNO 《International journal of cosmetic science》1987,9(5):203-214
The interactions between a typical range of perfume materials, alcohol, water, air, elevated temperatures and daylight have been studied. The changes of composition, acidity, peroxide content and the formation of new molecules were followed. The stabilizing effects of UV absorbers, antioxidants and sequestering agents were examined;
— the formation of acid reaction products was accelerated by air, temperature, daylight and the presence of natural products;
— peroxide formation was accelerated by heat and light and the presence of air; as the acidity increased, the peroxides decomposed;
— the acetalization of other aldehydes was accelerated by temperature and daylight and the presence of natural products up to 40% of certain aldehydes may be converted into acetals after 3 months at 37°C;
— many stereoisomerizations occur, e.g., transisoeugenol is converted up to 10% into the cis isomer after 3 months at 37°C and 58% in daylight;
— evaluation of antioxidants UV absorbers and sequestering agents showed a significant protection against deterioration only by EDTA dipotassium salt;
— ethanol was converted into acetaldehyde and its diethylacetal by peroxides present and formed on ageing up to 0.08%. Natural products accelerated this formation;
— the reaction between benzoyl peroxide and ethanol was shown to yield up to 63% of acetaldehyde+diethyl acetal whilst di-t-butyl peroxide gave only 23% under the same conditions.
These results go some way to explaining odour changes in perfume ageing. 相似文献
— the formation of acid reaction products was accelerated by air, temperature, daylight and the presence of natural products;
— peroxide formation was accelerated by heat and light and the presence of air; as the acidity increased, the peroxides decomposed;
— the acetalization of other aldehydes was accelerated by temperature and daylight and the presence of natural products up to 40% of certain aldehydes may be converted into acetals after 3 months at 37°C;
— many stereoisomerizations occur, e.g., transisoeugenol is converted up to 10% into the cis isomer after 3 months at 37°C and 58% in daylight;
— evaluation of antioxidants UV absorbers and sequestering agents showed a significant protection against deterioration only by EDTA dipotassium salt;
— ethanol was converted into acetaldehyde and its diethylacetal by peroxides present and formed on ageing up to 0.08%. Natural products accelerated this formation;
— the reaction between benzoyl peroxide and ethanol was shown to yield up to 63% of acetaldehyde+diethyl acetal whilst di-t-butyl peroxide gave only 23% under the same conditions.
These results go some way to explaining odour changes in perfume ageing. 相似文献
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