缩酮

Under the above conditions the yield of cyclohexanone 1, 2-propanediol ketal is 98.21%.

在此条件下，环己酮1， 2-丙二醇缩酮收率达到98.21%。

In this thesis, we describe a facile and economical synthesis of-abscisic acid from keto-isophorone and 3-butyn-2-ol through ketalization, oxidization, Witting-Horner reaction, reduction with chromium sulfate and other steps in 13% total yields. Compared to the previous routes, the starting materials are more commercially available and cheaper and the synthetic process is more easily controlled in our method, but the yield of this route is still to be improved.As to isostere principle, cyclopropyl and methyl vinyl are a couple of isostere.

本论文设计并完成了一条全新的外消旋脱落酸(1)全合成路线，从廉价的工业原料氧化异佛尔酮和丁炔醇出发，经过缩酮化反应、氧化反应、Wittig-Horner反应、CrSO_4选择性还原反应以及水解等七步反应实现了脱落酸的全合成，总产率达13％，与以往路线相比，该路线所用试剂廉价、合成路线简单，但产率有待提高。

The reaction time, the using regenerated catalyst on the yield of Cyclohexanonel, 2-propylene ketal were systematically investigated.

研究了杂多化合物K5CoW12O403H2O作为催化剂对环己酮和1， 2-丙二醇缩酮的催化活性。

Fe2(SO4)3/SiO2 catalyst is excellent in stability and reusability, and yield of cyclohexanone 1, 2-propanediol ketal keeps at 88.90% after being used for 5 times.

Fe2(SO4)3/SiO2催化剂具有良好的德定性，重复使用5次后环己酮1， 2-丙二醇缩酮的收率为88.90%。

The optimal conditions were found to be: n:n=1:1.5; mass fraction of catalyst to reactants, 1.0%; reaction time, 0.75 h and dried cyclohexane, 8 mL. Under these conditions, the yield of cyclohexanone ethylene ketal was 87.7%.

实验结果表明，在n∶n=1.0∶1.5、催化剂用量占反应物料总质量的1.0%、反应时间0.75 h的条件下，环己酮乙二醇缩酮的收率为87.7%。

Cyclohexanone ethylene ketal was synthesized using vitamin C as the catalyst by microwave irradiation solvent-free method.

以维生素C为催化剂，采用微波辐射无溶剂催化合成环己酮乙二醇缩酮，探索了不同反应条件对产率的影响。

Hβ zeolite ; seven-member-ring ketal ; 1; 4-butanediol ; synthesis ; catalyst

Hβ；七元环缩酮； 1； 4-丁二醇；环己酮；合成；催化剂

A new phenomenon that ketal can be deprotected by strong base NaH wasfound.

在实验过程中首次发现在强碱氢化钠作用下，缩酮结构能脱去保护基而复原为酮基这一现象。

The results showed that molar ratio of cyclohexanone to ethylene glycol was 1∶1.4, the amount of catalyst was 2% cyclohexanone, amount of cyclohexane was 10 mL, the reaction time 2 h, the yield of cyclohexanone ethylene ketal reached 99.6% under the optimum condition.

通过正交实验得出了最佳反应条件：n∶n=1∶1.4、催化剂用量为环己酮质量的2%、带水剂环己烷用量10.0 mL、反应时间2 h，缩酮产率可达99.6%。

Catalytic Synthesis of Cyclohexanone 1, 2-Propylene Ketal by Chitosan Supported with Iodine

篇名 壳聚糖负载单质碘催化合成环己酮1， 2-丙二醇缩酮

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。