新型吡咯类衍生物的合成

2,5-己二酮和胺(氨基硫脲、硫脲、苯胺、氨基酸)经过Paal-Knorr反应合成6个2,5-二甲基-N-取代吡咯衍生物;分别以新合成的N-吡咯甘氨酸、N-苯基吡咯化合物为原料,进行酯化反应和Mannich,Friedel-Craft反应,合成3个N-(2,5-二甲基吡咯)甘氨酸酯类化合物和2个N-苯基-2,5-二甲基吡咯衍生物.所有化合物都通过IR,1HNMR,13CNMR,HRMS波谱方法对其结构进行了确证.     

杯吡咯和杂杯吡咯的结构、合成与应用

杯吡咯以其特殊的结构和优异性能, 在主客体化学尤其是分子识别等方面的应用前景已备受关注, 合成新型功能化杯吡咯及其衍生物已成为超分子化学领域的研究热点之一. 近年来通过引入新型芳烃基体合成了结构和性能多样的杂杯吡咯. 主要介绍了功能化的杯吡咯和杂杯吡咯的结构、合成及其在分子识别等领域的应用.     

杯吡咯功能化合物的研究与应用

综述了近几年杯吡咯新型大环化合物在功能化修饰和分子识别等方面的研究进展.在近3年里,人们合成了许多新的meso- 、C-rim修饰的,腔体被延伸化的和环体扩张的杯吡咯大环化合物.主要讨论了功能化衍生物的合成、色谱固定相、分子识别作用及其在阴离子传感器上的应用.     

CuI催化吡咯酰胺化反应合成吡咯-1-酰胺化合物

吡咯衍生物具有良好的生物活性，是很多药物和天然产物分子的重要组成部分。此外，吡咯衍生物在抗菌、抗结核、抗病毒、抗疟疾以及抗癌等方面的应用也非常广泛。本文报道了温和条件下，Cu(I)催化吡咯与异氰酸酯N-甲酰胺化制备吡咯-1-酰胺化合物的反应，开发了一种简便的方法合成吡咯-1-酰胺化合物。该方法对多种异氰酸酯具有很好的适用性，均能以较高产率获得相应目标产物。与文献方法相比，本方法具有高效、操作简便、反应条件温和等优点。      

基于吡咯骨架的不对称傅克反应研究进展

手性吡咯化合物是一类重要的五元含氮杂环化合物,广泛存在于众多有生物活性的天然产物中.利用不对称傅克反应合成手性吡咯化合物一直是有机合成的研究热点之一.利用手性有机小分子和手性金属催化剂是实现不对称合成手性吡咯化合物最为常见的方法.根据催化剂的分类,我们就近十几年来基于吡咯结构单元的不对称傅克反应的研究进展进行简要阐述.     

多取代吡咯基脂肪酸的合成

许多吡咯衍生物具有生理活性,近年来发现1-芳基取代吡咯具有明显的生理效应,作者曾合成了部分多取代吡咯化合物,并研究了其NMR谱。     

溴化二甲基溴化硫催化下合成N-取代吡咯类化合物

室温、无溶剂条件下,以溴化二甲基溴化硫(BDMS)为催化剂,以2,5-己二酮和伯胺类化合物为原料,能高收率的实现一系列N-取代吡咯衍生物的合成.所有化合物结构通过1H NMR,13C NMR和元素分析确定.     

烯胺酮（酯）参与的串联反应构建吡咯衍生物的研究进展

作为多位点的有机合成子,烯胺酮（酯）参与的串联反应广泛应用于吡咯衍生物的合成。综述了烯胺酮（酯）与邻二羰基化合物,β 硝基烯烃和苯乙炔等参与的串联反应在吡咯单环和稠环衍生物合成中的应用进展,并对其未来发展进行了展望。参考文献49篇。     

水溶液中一步合成二吡咯甲烷类化合物

在水相中,以磷钨酸为催化剂,吡咯与羰基化合物为底物,室温下一步合成了二吡咯甲烷类化合物,反应产物纯度高,无需进一步纯化.该方法具有明显的环境友好、产率高和操作过程简便的优点.     

双-[2-吡咯(乙氧基)]乙烷的合成及其电化学聚合

以吡咯和二缩三乙二醇为原料合成了N取代吡咯衍生物单体--双-[2-吡咯(乙氧基)]乙烷,并用循环扫描伏安技术研究了该单体的电化学聚合过程.结果表明:在乙腈/高氯酸锂溶液中,双-[2-吡咯(乙氧基)]乙烷在铟锡氧化物导电玻璃(ITO)、Pt、Au、玻璃碳、石墨电极上均能顺利发生反应,形成一定厚度的聚合物膜.但聚合速率、膜的结构、膜的颜色有差异.溶剂水对聚合有明显影响.形成的聚合膜具有良好的电化学稳定性.     

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.     

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%).     

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.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.