查询词典 piperonal

The Pictet-Spengler reaction of D-tryptophan methyl ester hydrochloride II-42 with piperonal II-34 in various solvents was extensively studied. The best stereoselectivity (cis/trans=99:1) was obtained using nitromethane or acetonitrile as the solvent.

我们研究了在不同溶剂中，D-色氨酸甲酯盐酸盐II-42和胡椒醛II-34发生的Pictet-Spengler反应的立体选择性，发现当分别用硝基甲烷和乙腈做溶剂时反应的立体选择性达到最高， cis：trans的比例为99： 1。

In the synthesis process of ligands and their rare earth complexes, metal lithium is used to substitute for n-butyllithium, such as the synthesis of fluorenyl lithium, piperonal dimethyl acetal lithium, and bis (9-fluorenyl) silylene lithium.

合成配体和配合物的中间体均采用金属锂代替正丁基锂，如芴锂、溴代胡椒醛二甲基缩醛基锂盐、甲基苯基双芴基硅烷双锂盐的制备，方法简单，操作简便，副反应少，且锂盐的浓度和用量易于控制。

Starting from piperonal, the initial total synthesis of CET involved BischlerNapieralski reaction, 3, 2-sigmatropic rearrangement, unusual Nazarov-type electrocyclization, and autoxidative dehydrogenation of desmethylcephalotaxine to desmethylcephalotaxinone etc.

第一条路线我们以胡椒醛为起始原料，经Bischler-Napieralski反应，[3，2]-σ重排，6-6环系到7-5环系的还原重排，Nazarov氧化环化；碱性条件下脱甲基三尖杉碱到脱甲基三尖杉酮碱的氧化脱氢等20步反应，完成了三尖杉碱的全合成。

We are the only manufacturer of Piperonal through rauvite natrium oxidizing production low, and its annual output is 120 tons. We are also the only manufacturer of Raspberry ketone through phenol production line, and its annual output is 200 tons. The curatorial intermediate, F101 Composite resin rubber sulfidizer, and high molecular materials are new and high-tech products first developed in China with the quality reaching international level. The leather chemical product-basic chromium sulphate has won the Scientific and Technological Reward of Suzhou City, and has been taken as reference for The Ministry of Science and Technology of The PRC formulating standard.

年销售8000万元，其中香料产品洋茉莉醛用红矾钠氧化法生产线，目前国内独此一家，年产量达120吨；覆盆子酮用苯酚路线生产的产量达200吨国内独此一家；医药中间体，橡胶类F101复合树脂硫化剂，高分子材料类属高新技术产品，国内首创，质量达到国际水平；皮革化工"碱式硫酸铬"等获得苏州市科技成果奖，并参与国家技术部制定标准。

Keywords piperonal;acetone;synthesis;claisen-schmidt reaction;4-（1;3-benzedioxole）-3-buten-2-one

洋茉莉醛；丙酮；胡椒烯丙酮；合成；克莱森-施密特反应

Under the protection of purified water-free, oxygen-free argon, using Schlenk technique, the rare rarth organometallic complexes containing piperonal dimethyl acetal and dicyclopentadienyl and involving silylene-bridged fluorenyl have been synthesized.

合成了含胡椒醛二甲基缩醛基和二茂基稀土金属有机配合物。采用Schlenk技术，在干燥纯氩气保护下进行。将溴代胡椒醛二甲基缩醛基锂盐与二茂基一氯稀土（Ln：Yb，Dy，Pr，La，Sm）反应，形成5个新的文献未曾报道的稀土金属有机配合物。

Main production and management projects: piperonyl butoxide, Piperonal aldehyde, C Piperonyl aldehyde, PMK, eucalyptus oil, according to pituitrin, citral, ionone, cubeba oil, Geranium oil, 99 % natural a bit terpineol, pine oil acetate, sassafras oil, natural spices; run: Fragrance, tobacco flavor, food flavor, natural flavor essence seasoning products.

胡椒基丁醚、洋茉莉醛、胡椒基丙醛、胡椒基甲基酮、桉叶油、按叶素、柠檬醛、紫罗兰酮、山苍子油、香叶油、99%天然甲位松油醇、乙酸松油脂、黄樟油等天然香料；兼营：日化香精、烟用香精、食用香精、调味品香精等天然香精产品等。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。