Synthesis of Cycloundecanone from Benzimidazole Methiodide Salt

Cycloundecanone has been synthesized in several ways. Fawcett et al. prepared cycloundecanone by the reduction of Z-hydroxycycloundecanone'. Ruzicka et al. reported thesynthesis of cycloundecanone by the pyrolysis of the thorium salt of dodecanedioic acid=.Schank and Eistert synthesized cycloundecanone by ring contraction ofcyclododecanone'.Garbisch et al. improved the ring contraction reaction in over-all yields consistentlyranging between 85 and 90%'. Garbisch's method gave higher yields a…     

手性双唑啉铜配合物在不对称合成中的应用

综述了手性双E唑啉配体的主要结构类型,并讨论了手性双E唑啉铜配合物在不对称Diels-Alder反应、Ene反应、Mukaiyama adol反应、烯丙基氧化、环丙烷化、氮杂环丙烷化等反应中的应用。     

Novel Synthesis of α‐Diketones from Bisbenzimidazolium Salt and Grignard Reagents

The reaction of bisbenzimidazolium salt with Grignard reagents and a new synthetic method of a‐diketones from bis‐benzimidazolium salt and Grignard reagents are reported. The structures of all a‐diketones are characterized by elemental analyses, infrared spectroscopy and ¹H NMR spectroscopy. The influences of the various Grignard reagents on the yield of a‐diketones and the mechanism are discussed, and a new convenient synthetic method for a‐diketones is provided.     

bronsted酸性离子液体催化合成阿司匹林

以邻苯二胺和环丙基甲酸为原料,以多聚磷酸(PPA)为催化剂,在微波辐射下合成了环丙基苯并咪唑,用碘甲烷季胺化得到未见文献报道的环丙基苯并咪唑盐,通过苯并咪唑盐与Grignard试剂加成后水解反应制备环丙基甲基酮。经元素分析和红外光谱、质谱、核磁共振测试技术表征确证了结构。环丙基甲基酮为无色液体,合成环丙基甲基酮方法的产率为67%,为环丙基甲基酮提供了一种未见文献报道的合成方法。     

Activation by the Grignard reagent of the bis(2-phenylindenyl)zirconium dichloride—triisobutylaluminum catalytic system for propene polymerization

Polymerization of propylene with the three-component catalytic system bis(2-phenylindenyl)zirconium dichloride—alkyl magnesium chloride—triisobutylaluminum is studied. The annelated zirconocene is alkylated by the Grignard reagent. The three-component system is as good in activity as two-component systems with polymethylalumoxane as a cocatalyst. Stereoblock elastomeric polypropylene with a high molecular weight is formed.     

从四氢叶叶酸辅酶模型合成麝香酮中间体2,1 5-十六二.酮

麝香酮是麝香中重要的具有生理活性的组分.自Ruzicka[1]确定其结构以来,化学家研究和发展了许多合成麝香酮的方法[2].Stoll[3]提出的由2,15-十六二酮经分子内环合后氢化得到麝香酮,其操作简便,但尚需解决2,15-十六二酮的来源问题.5,6,7,8-四氢叶酸辅酶在生物体内的功能和作用及仿生合成已成为仿生化学研究的重要课题[4].四氢叶酸辅酶在生物体内传递不同氧化态的-碳单元,当-碳单元处于甲酸氧化态时,活性部位是形成的咪唑啉环[5,6].因此,本文以咪唑啉盐作为四氢叶酸辅酶模型,与亲核试剂双格利雅试剂作用,仿生合成2,15-十六二酮.     

Novel Synthetic Method for Triacetylbenzene

Triketones are an important class of compounds in view of the distinct structure feature and wide utility in macromolecular material, organic synthesis and coordination chemistry1. The synthetic method for preparing symmetrical triketones 1, 3, 5- triacetylbenzene reported by Robert et al. is via condensation of acetone with ethyl formate followed by the trimerization of the intermediate acetylacetaldehyde2. We reported the reaction of benzimidazolium salts with Grignard reagents, providing a …     

一种新型的可见光诱导电子转移生酸体系的研究

对 4种分子内共轭的电荷转移化合物和取代的双 (三氯甲基 ) 2 ,4,6 三嗪分子间的光诱导电子转移和光生酸反应进行了详细研究 .通过荧光猝灭和体系荧光随时间的变化可看到作为电子受体的三嗪分子和作为电子给体电荷转移化合物间的光诱导电荷转移作用 .在对体系酸度的测定中 ,可清楚地看到体系经光照后所发生的变化 .对所研究生酸体系引发酚醛树脂 六甲氧基甲基三聚氰胺交联反应的能力进行了初步研究 .对可能发生的反应机制进行了讨论     

含有给电子生色团的双马来酰亚胺与脂肪二胺的共聚合及其荧光光谱跟踪

我们曾合成了一系列含有给电子生色团的丙烯酰类单体 ,它的给电子本质主要是由氮原子 ,以Ｎ ,Ｎ 二甲基氨基苯基的形式所贡献[1～ 4] ,即 :Ｎ ( 4 Ｎ′,Ｎ′ 二甲氨基苯基 )马来酰亚胺 ,Ｎ ( 4 Ｎ′ ,Ｎ′ 二甲氨基苯基 )丙烯酰胺 ,Ｎ ( 4 Ｎ′ ,Ｎ′ 二甲氨基苯基 )衣康酰胺 ,甲基丙烯酸 (对 4 Ｎ ,Ｎ 二甲氨基 )苄酯 ,这些单体的荧光发射强度总是远远低于相同浓度聚合物的荧光强度 .为了区别所熟知的荧光浓度自猝灭 ,我们称这种现象为结构自猝灭效应 (ＳＳＱＥ) [1～ 5] .具有ＳＳＱＥ的丙烯酰类单体可表示为Ａ( =) Ｄ( ) 型化合物 …     

疏水缔合(丙烯酰胺十六烷基二甲基烯丙基氯化铵-2-丙烯酰胺基-2-甲基丙磺酸)三元共聚物的合成与性能研究

疏水缔合水溶性聚合物是指在聚合物亲水性大分子链上引入少量疏水基团的一类水溶性聚合物[1～5].在水溶液中,疏水基团之间由于憎水作用而发生聚集,使大分子链产生分子内与分子之间缔合.在临界缔合浓度以上,以分子间缔合为主,增大了流体力学体积,因此,具有较好的增粘作用.疏水基的加入可大幅度地改变聚合物的流变性能.在聚合物驱油中的流度控制,提高波及效率、以及调剖中起到非常重要的作用.     

2，5-联苯二甲酸的新合成方法

铁粉催化下,对二甲苯于室温与溴反应,得到2－溴对二甲苯,将其制备成相应的格氏试剂,在NiCl2(PPh3)2催化下与溴苯进行交叉偶联,得到2,5－二甲基联苯,再用高锰酸钾水溶液氧化,合成标题化合物,产物的结构由IR确认。     

龙葵醛的新合成方法研究

龙葵醛是一种珍贵的香料 ,也是重要的化工原料 ,广泛应用于香料、医药、染料及农药等行业 .龙葵醛的工业生产以苯乙酮和一氯醋酸乙酯为原料 ,按 Darzens法合成[1,2 ] .苯乙酮与一氯醋酸乙酯在强碱作用下制得甲基苯基环氧丙酸酯 ,该酯经皂化、中和、水解成酸 ,再将该酸加热分解 ,得龙葵醛 .该方法操作比较复杂 ,产率和产品纯度也不高 .为了寻找产率高、纯度好且成本低的新制备方法已有广泛的研究 .Rivero等 [3]提出的 2 -甲基苯乙醇氧化法 ,尽管产率较高 ,但反应温度要在 -78℃ ,不利于工业化生产 .陈万之等[4 ] 利用各种铑螯合物作为催化剂…     

Novel Synthetic Method for Muscone

Muscone is a precious fragrant compound scarce in nature. Many attempts to synthesize this unique natural product have been carried out. In this work, a novel synthetic method for the preparation of muscone from 3‐methyl‐15‐hydroxypentadecanoate is provided. Benzimidazolium salt was used as tetrahydrofolate coenzyme model at formic acid oxidation level and Grignard reagent as nucleophile to which a one‐carbon unit was transferred. The biomimetic synthesis of muscone was successfully accomplished using the addition‐hydrolysis reaction of benzimidazolium salt with the Grignard reagent.     

The Kharasch type reaction of allylic halides with Grignard reagent in the presence of transition metal halides

The reaction of allylic halide with Grignard reagent in the presence of transition metal chloride has been investigated. Three reactions of allylic halide occurred competitively; (i) reduction to olefin, (ii) coupling with Grignard reagent to olefin (cross-coupling) and (iii) coupling with itself to 1,5-diene (homo-coupling). The relative importance of these reactions depends on both the structures of allylic halide and Grignard reagent, as well as on the transition metal salt utilized. The mechanism was discussed in terms of the allylic transition metal intermediate.     

A Simple Route to New Cyclic (Chloroalkyl)phosphane‐, Diphosphane‐, and Aminophosphane Derivatives

The reaction between benzothiadiphosphole and, in sequence, a bis‐Grignard and a chloroalkyl Grignard reagent has been reported. It produced, after treatment of the crude reaction mixture with elemental sulfur, new chloroalkyl cyclic tertiary phosphane sulfides. These compounds have been successfully employed as precursors of new nonsymmetric phosphoamino and diphosphano derivatives.     

铁、钴催化剂乙烯聚合原位紫外-可见光谱研究

利用乙烯常压聚合原位紫外 可见 (UV Vis)光谱技术 ,对 3个铁、钴络合物作为催化剂前体的催化剂体系进行了研究 .3个铁、钴络合物分别为 2 ,6 双 [1 (2 ,6 二甲基苯基亚胺 )乙基 ]吡啶二氯化铁 (a)、2 ,6 双 [1 (2 ,4,6 三甲基苯基亚胺 )乙基 ]吡啶二氯化铁 (b)和 2 ,6 双 [1 (2 ,6 二异丙基苯基亚胺 )乙基 ]吡啶二氯化钴(c) .实验结果表明 ,MAO对络合物催化剂前体的活化作用是一个快速过程 ;在聚合条件下分别观察到 5 6 0、6 30和 5 80nm的活性峰 ,考察了它们在聚合过程中的生长和在加入无水乙醇逐步使催化剂中毒时活性峰的消失规律 .对催化剂活性物种的结构和聚合机理进行了探讨     

水溶性聚酯浓溶液的流变特性

研究了由对苯二甲酸二甲酯、间苯二甲酸、间苯二甲酸二甲酯 5 磺酸钠与乙二醇等共缩聚合成的PET型水溶性聚酯浓水溶液 (质量浓度 3 0 % )的流变特性 .研究表明 ,溶液的表观粘度随切变速率的变化规律呈现一定的切力增稠特征 ,流动指数范围为 1 0 4～ 1 2 0之间 ;其lgηa τ曲线呈线性 ,零切粘度值为 1 5 8～3 5 2cP ,随分子量、分子结构和温度而异 ,其中分子链中间苯二甲酸乙二醇酯 5 磺酸钠链节含量对溶液粘度影响较大 ;粘流活化能因分子结构和切变速率而变 ,其值范围为 1 2 0～ 2 3 9kJ/mol.     

聚苯乙烯基偶氮聚合物的合成研究

改进了聚苯乙烯的硝化、还原、重氮化和偶合反应路线 (NRDC) ,使每步反应都得到很高的产率 ,并利用大分子重氮盐 (MDS)分别与苯胺、N 烃基苯胺和酚等三类化合物偶合 ,得到相应的聚苯乙烯基偶氮聚合物 .核磁共振分析结果证明了产物的高偶联率 .通过对大分子重氮盐热稳定性的研究 ,发现偶合反应之后需要一步加热反应以消除残余重氮基团 .还研究了这些聚合物的紫外 可见吸收光谱性质 ,氨 (胺 )基偶氮产物的水溶液表现出了明显的pH敏感性     

Sequential One‐Pot Addition of Excess Aryl‐Grignard Reagents and Electrophiles to O‐Alkyl Thioformates

The sequential addition of aromatic Grignard reagents to O‐alkyl thioformates proceeded to completion within 30 s to give aryl benzylic sulfanes in good yields. This reaction may begin with the nucleophilic attack of the Grignard reagent onto the carbon atom of the O‐alkyl thioformates, followed by the elimination of ROMgBr to generate aromatic thioaldehydes, which then react with a second molecule of the Grignard reagent at the sulfur atom to form arylsulfanyl benzylic Grignard reagents. To confirm the generation of aromatic thioaldehydes, the reaction between O‐alkyl thioformates and phenyl Grignard reagent was carried out in the presence of cyclopentadiene. As a result, hetero‐Diels–Alder adducts of the thioaldehyde and the diene were formed. The treatment of a mixture of the thioformate and phenyl Grignard reagent with iodine gave 1,2‐bis(phenylsulfanyl)‐1,2‐diphenyl ethane as a product, which indicated the formation of arylsulfanyl benzylic Grignard reagents in the reaction mixture. When electrophiles were added to the Grignard reagents that were generated in situ, four‐component coupling products, that is, O‐alkyl thioformates, two molecules of Grignard reagents, and electrophiles, were obtained in moderate‐to‐good yields. The use of silyl chloride or allylic bromides gave the adducts within 5 min, whereas the reaction with benzylic halides required more than 30 min. The addition to carbonyl compounds was complete within 1 min and the use of lithium bromide as an additive enhanced the yields of the four‐component coupling products. Finally, oxiranes and imines also participated in the coupling reaction.     

The synthesis of phosphine oxide-linked bis(oxazoline) ligands and their application in asymmetric allylic alkylation

The phosphine oxide-linked bis(oxazoline) ligands were designed and synthesized in two ways. One is the coupling of Grignard reagent derived from 2-(2-bromophenyl)oxazoline with phenylphosphonic dichloride, another route is the condensation of bis(2-formylphenyl)(phenyl)phosphine oxide with chiral amino alcohols followed by NBS oxidation. These new bis(oxazoline) ligands were applied in Pd-catalyzed asymmetric allylic alkylation reactions and good yields and enantioselectivities were obtained with diphenyl substituted ligand (up to 95% ee).