手性Schiff Base-Ti(OR)4配合物催化醛的不对称硅腈化反应

设计合成了新型手性Salen-Ti(OR)₄配合物催化剂,用其催化一系列醛的不对称硅腈化反应,得到了e.e.值为22.4%～87.1%的氰醇.催化剂中抗衡离子的Lewis碱强烈地影响催化活性,但对反应的对映选择性影响很小,并探讨了其不对称催化反应机理.     

CdS纳米粉体的合成新方法——一步室温固相化学反应法

ＣｄＳ纳米粉体的合成新方法——一步室温固相化学反应法俞建群贾殿赠＊张慧周蓉夏熙（新疆大学化学系乌鲁木齐８３００４６）室温或近室温条件下的固－固相化学反应是近几年刚发展起来的新研究领域，经过近几年的研究，已在合成化学中取得良好的应用［１，２］，并总结得...     

16-脱氢孕烯醇酮醋酸酯的环境友好合成法

Instead of environmentally toxic chromium oxidant, singlet oxygen generated photcchemically was used as environmentally friendly and benign oxidizing agent to accomplish the transformation of pseudodiosgenin diacetate to diosone efficiently in a low toxic and less expensive solvent acetone. Accordingly 16-dehydropregnenolone acetate(16-DPA), an important intermediate for preparation of steroidal drugs, was prepared in good yield (75%) when photoreaction was run in acetone/acetic anhydride/pyridine system. The mild reaction condition as well as simple and environmentally friendly process made the method commercially viable and important for production of 16-DPA in industrial scale.     

碱性介质中分光光度法研究二羟基二(过碘酸根)合银(Ⅲ)氧化谷氨酸的反应动力学及机理

在碱性介质中,用分光光度法研究了二羟基二(过碘酸根)合银(Ⅲ)(DPA)氧化谷氨酸(GA)的反应动力学及其机理.结果表明,反应对DPA为准一级,对GA为一级反应;在保持准一级条件([GA]₀[DPA]₀)下,表观速率常数随着[OH^-]的增加先减小后增加,随着[IO₄^-]的增加而减小,且有正盐效应.据此提出了此反应的反应机理,由此反应机理推导出来的速率方程可很好地解释全部实验现象,进一步求得速控步骤速率常数k和298.2K时的平衡常数K及活化参数.     

Ring-closing Metathesis on an Allyl-terminated Carbosilane Dendrimer

Grubbs‘ catalyst was used to prepare a series of carbosilane dendrimers with silacyclopentene peripheral groups. It was found that ring closing metathesis reaction was influenced strongly by the reaction temperature and the amount of catalyst.     

Cu（I）/Diamine-catalyzed Aryl-alkyne Coupling Reactions

Arylalkynes are important building blocks for the synthesis of natural products,pharmaceuticals,and artificial molecular devices1.They are often synthesized via the Pd-catalyzed Sonogashira coupling reactions between aryl halides and terminal alkynes2,3.Unfortunately,it remains difficult to apply the Sonogashira reaction to industrial scale and/or pharmaceutical synthesis,due to the high cost of Pd and the difficulty in removing the toxic Pd residues from the reaction products.Thus it is wor…     

6,7-二甲氧基-2-苯乙烯基喹啉的合成

在乙醇钠催化下,6-氨基藜芦醛与卞叉丙酮发生Friedlainder缩合反应得到新化合物6,7-二甲氧基-2-苯乙烯基喹啉,产率59％。其结构经UV,^1H NMR,IR和MS表征。     

2,3,7,8-四甲氧基-11氢-茚并[1,2-b]喹啉的合成

以藜芦醛为起始原料,经硝化、还原得到邻氨基藜芦醛(3)。3与5,6-二甲氧基-1-茚酮发生Friedlander缩合反应,合成了新化合物2,3,7,8-四甲基-11氢-茚并[1,2-b]喹啉。其结构经UV,^1H NMR,IR和MS表征。     

新显色剂1-(6-羟基-2-嘌呤基)-3-[4-(苯基偶氮)苯基]-三氮烯的合成及与镉的显色反应

合成了新显色剂1 (6 羟基 2 嘌呤基) 3 [4 (苯基偶氮)苯基] 三氮烯(简称HPAPT),研究了它的性质及其与镉显色反应的条件。实验表明,试剂的分子式为C17H13N9,相对分子质量为359,熔点127～129℃,各级酸离解常数为pKa1=4.1,pKa2=7.2,pKa3=10 7。在pH9.0～11.0的Na2B4O7 NaOH缓冲介质中,试剂与镉形成2∶1的红色络合物,表观摩尔吸光系数为2 25×105L·mol-1·cm-1,镉质量浓度在0～0.6mg/L范围内符合比耳定律,在联合掩蔽剂的作用下,可不经分离直接测定环境水样和工业废水中微量镉。