二茂铁基-1,1’-二烷基二茂铁甲醇的合成与性质

10种二茂铁甲酰基 -1 ,1 -二烷基二茂铁经 Li Al H4还原得到 1 0种相应的二茂铁基 -1 ,1 -二烷基二茂铁甲醇 .这类羟基化合物对酸的敏感性很高 .由 2种二茂铁基 -1 ,1 -二乙基二茂铁甲醇与 BF3在二氯甲烷中反应形成了稳定的二茂铁基 -1 ,1 -二乙基二茂铁甲基碳正离子 .无需从反应混合物中分离 ,该离子与乙胺作用得到了 2种 N-取代产物 .由元素分析、红外光谱和核磁共振氢谱证实了化合物的结构     

二茂铁基-1,1＇-二烷基二茂铁甲醇的合成与性质

10种二茂铁基－1,1'-二烷基二茂铁经LiAlH4还原得到10种相应的二茂铁基－1,1'-二烷基二茂铁甲醇。这类羟基化合物对酸的敏感性很高。由2种二茂铁基－1,1'-二乙基二茂铁甲醇与BF3在二氯甲烷中反应形成了稳定的二茂铁基－1,1'-二乙基二茂铁甲碳正离子。无需从反应混合中分离,该离子与乙胺作用得到了2种N－取代产物。由元素分析、红外光谱和核磁共振氢谱证实了化合物的结构。     

二茚基二芳氧基锆催化乙烯齐聚

直链低碳α 烯烃是生产线性低密度聚乙烯 (ＬＬＤＰＥ)和高密度聚乙烯 (ＨＤＰＥ)的共聚单体 .Ｋａｍｉｎｓｋｙ型催化剂是 80年代发展起来的烯烃高效聚合催化剂[1].近年来亦有文献报道该类催化剂催化乙烯齐聚合成低碳α 烯烃[2～ 5].而以茚基锆化合物与氯化烷基铝所组成的催化体系催化乙烯齐聚还未见文献报道 .本文考查了茚基锆化合物和一氯二乙基铝所组成的二元催化体系对乙烯齐聚的催化性能 ,合成了Ｉｎｄ2 Ｚｒ(ＯＣ6 Ｈ4 ｐ Ｍｅ) 2 、Ｉｎｄ2 Ｚｒ(ＯＣ6 Ｈ5) 2 、Ｉｎｄ2 ＺｒＣｌ2 和Ｃｐ2 Ｚｒ(ＯＣ6 Ｈ4 ｐ Ｍｅ) 2 4个化合物 ,…     

多二茂铁基二氮杂己烷及其过渡金属配合物的合成

乙二胺与二茂铁甲醛或双二茂铁甲基氟硼酸盐反应，合成了１，６－二（二茂铁基）－２，５－二氮杂己烷和１，１，６，６－四（二茂铁基）－２，５－二氮己烷，它们与过渡金属（Ｆｅ＾２＋，Ｃｏ＾２＋，Ｎｉ＾２＋，Ｃｕ＾２＋，Ｚｎ＾２＋）盐在乙醇或乙醇－二氯甲烷中反应，是１４种过渡金属配合物，对这些化合物进行了表征，二种配体及其铜配合物用作复合固体推进剂的燃速调节剂时，基本不迁移，而燃速催化效率均超过辛基二茂铁。     

N-二茂铁甲酰基-芳基羟胺及其铜(Ⅱ)螯合物的合成与表征

二茂铁甲酰羟胺衍生物分子中含有N-羟基和α-羰基,可与过渡金属形成螯合物.我们试图将该类螯合物用作复合固体推进剂的燃速调节剂,为此,研究了该类化合物的合成方法及其性质,并使它们与铜(Ⅱ)螯合制成铜螯合物.     

混合三聚反应及结构的研究——Ⅱ.单核及双核铁混合三聚反应的研究

通过甲酰基二茂铁与取代水杨醛和氨反应,直接合成了含一个二茂铁的混合三聚产物,N,N′-二[2-羟基-5-取代苄烯]二茂铁甲二胺.茂环上碳原子的化学位移~(13)CNMR与苯环上R取代基的Hammett常数之间存在着很好的线性关系.循环伏安法测出的E_(1/2)也与Hammett常数之间存在着很好的线性关系.通过混合三聚反应,也合成了另一类含两个二茂铁化合物,N,N′-二[二茂铁甲烯]-2-羟基-5-特丁基苯甲二胺.~1H及~(13)CNMR表明,分子内由于氢键和立体效应的影响,导致两个茂环上的化学环境不等性.     

二茂铁基正庚基β－二酮的合成及晶体结构

在氢化钠存在下，用乙酰基二茂铁与正辛酸乙酯进行缩合反应，合成了标题化合物ＦｅＣＯＣＨ_２ＣＯＣ_７Ｈ_（１５）（Ｆｃ＝Ｃ_５Ｈ_５ＦｅＣ_５Ｈ_４）．Ｘ射线衍射测定其晶体学数据为：Ｃ_（２０）Ｈ_（２６）ＦｅＯ_２，空间群Ｐ２_１／ｎ，ａ＝０．５７９０（１）ｎｍ，ｂ＝４．１６３４（４）ｎｍ，ｃ＝０．７６３５（１）ｎｍ，β＝１０１．３９（１）°，Ｚ＝４．最终的偏离因子Ｒ＝０．０５０．结构分析表明，该化合物分子以烯醇式形式存在，通过分子内氢键，形成六元环，环中Ｏ…Ｈ氢键距离为０．１４６ｎｍ．β－二羰基中与正庚基相连接的羰基易于烯醇化。     

二烷基二茂铁甲酰化反应的研究

甲酰基二茂铁是一种极为重要的二茂铁衍生物。以它为中间体 ,经缩合、还原和氧化等反应 [1～ 3] ,可得到许多其它的二茂铁化合物。在甲酰基二茂铁分子中引入烷基后 ,其性质在两个方面会发生显著变化。一是含碳量增加 ,导致其衍生物在有机溶剂中的溶解度增加 ;另一是化合物的物态发生了很大变化 ,固态会变为液态 ,高熔点物会变为低熔点物 ,为合成液态或低熔点二茂铁化合物提供了丰富的中间体。有关二烷基二茂铁甲酰化反应的报道甚少[4 ] ,更未见系统地研究过多种不同烷基的引入对甲酰化反应的影响。为此我们研究了 6种二烷基二茂铁的 Vilsme…     

双核茂铁四氮唑的合成及对高氯酸铵热分解的催化作用

首先以二茂铁为原料合成丙基桥联的双聚二茂铁(DFP), 经甲酰化得到丙基桥联的双聚二茂铁甲醛(DFP-CHO, 1), 再与NH₂OH·5HCl进行缩合反应得到双核二茂铁肟(2), 然后脱水得到丙基桥联双聚二茂铁甲腈(3), 最后在(n-C₄H₉)₃SnCl 的催化作用下与NaN₃进行[2+3]环加成反应, 生成目标产物丙基桥联双聚二茂铁四唑(4); 通过¹H NMR, FTIR和ESI-MS对目标产物的结构进行了表征. 利用差示扫描量热分析(DSC)和热重(TG)分析研究了这2个双聚二茂铁氮杂衍生物的燃速催化性能, 结果表明, 通过添加质量分数为5%的丙基桥联双聚二茂铁氮杂化合物3和4均使高氯酸铵(AP)的热分解温度降至100℃左右.     

N,N′-双(二茂铁甲酰)乙二胺与β-环糊精的相互作用

N; N′-双(二茂铁甲酰)乙二胺与β-环糊精的相互作用;二茂铁;β-环糊精;主客体相互作用     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.