Applications of Polymeric Reagents in Organic Synthesis

Summary. Polymer supported reagents have found many applications in recent years. Scientists in research laboratories of agrochemical and pharmaceutical industries now routinely utilize these compounds to prepare ensembles of small organic molecules for screening. This review is aimed to highlight some of the most important applications of these promising materials in organic synthesis. Furthermore, an extensive listing of polymeric reagents that were recently used in organic synthesis is included.     

高分子试剂的特性及其在分析化学中的应用

本文论述了可溶性高分子反应体系的特性,以及高分子分析试剂在分析化学中的应用前景。     

Polymers as Reagents in Organic Synthesis

Polymeric reagents offer a range of unique advantages. Intramolecular reactions, such as the cyclization of peptides or Dieckmann cyclizations, can be brought about by attaching the reactive molecules at remote points along a polymer chain. In contrast, if the reactive molecules are anchored in close proximity on a polymeric support then intermolecular reactions occur, as demonstrated for a ketone synthesis. Apart from such proximity effects, cooperative effects can also be exploited, e.g. in the formation of a 2:1 complex of a crown ether and an alkali metal ion. The hydrolysis of an ester with polyvinylimidazole provides a detailed illustration of hydrophobic interactions. The simple separation of polymer-bound and low-molecular compounds by filtration is another significant advantage.     

钐试剂在有机合成中的应用

本文综述了钐试剂在有机合成中的应用,包括还原反应,碳-碳键形成反应以及催化作用。     

应用手性高分子试剂和催化剂的不对称有机合成反应

不对称有机合成是有机化学的前沿课题之一.本文综述了应用手性高分子试剂和催化剂对潜手性化合物通过不对称氧化、还原、烷基化、加成反应进行不对称合成的进展情况.     

有机硅试剂在药物合成中的应用

主要介绍了有机硅试剂作为保护剂对药物结构中含有羟基、羧基、不饱和键、氨基、羰基和其它官能团的保护及应用情况,以及在合成中间体烯醇硅醚等方面的应用.     

有机锡试剂在有机合成中的某些新应用

本文阐述有机锡试剂在有机台成巾的一些新应用。在钯催化下,有机锡试剂与亲电试剂进行偶联,条件温和,收率高。有机锡试剂促进醇醛缩合,可用于不对称合成中。     

Polymeric Reagents.II. Synthesis and Applications of Crosslinked Poly(vinylpyridinium Hydrobromide Perbromide) Resins

Crosslinked bead polymers containing vinylpyridine units were prepared by pearl copolymerization of monomer mixtures containing various percentagesof 4-vinylpyridine, styrene, and di-vinylbenzene. The polymers were functionalized by reaction with hydrogen bromide and bromine, and the resulting poly-(vinylpyridinium hydrobromide perbromide) resins, which were stable for long periods of time, were used to brominate a number of alkenes and ketones. In most cases, the brominated products were obtained in excellent yields and could be separated from the polymeric by-product by a simple filtration. The polymeric reagent could be fully regenerated after use without loss of activity.     

The Analytical Applications of Organic Reagents in Hydrophobic Gel Media

Abstract

The use of hydrophobic gel particles containing an organic solvent solution of chelating agents is described. With the use of a column of such gel particles, it is possible to trap or concentrate metal ions selectively on the gel particles from very dilute aqueous solution. A method for the semi-quantitative determination of trace amount of metal ions is proposed.     

Rediscovering Sulfinylamines as Reagents for Organic Synthesis

Sulfinylamines (R−N=S=O), monoaza analogues of sulfur dioxide, have been known for well over a century, and their reactivity as sulfur electrophiles and in Diels-Alder reactions is well-established. However, they have only rarely been used in organic synthesis in recent decades despite the increasing prominence of compounds containing N=S=O functionality, such as sulfoximines and sulfonimidamides. This Minireview aims to bring wider visibility to the unique chemistry enabled by this class of compounds. We focus on advances from the last 10 years, including the first examples of their use in the one-pot syntheses of sulfoximines and sulfonimidamides. Also covered are the reactions of sulfinylamines with carbon-centred radicals, their use for formation of heterocycles through cycloadditions, and catalytic enantioselective allylic oxidation of alkenes via a hetero-ene reaction. These examples highlight the different reactivity modes of sulfinylamines and their underappreciated potential for forming molecules which contain high- or low-valent sulfur, or even no sulfur at all.     

固载氧化剂在有机合成中的应用

对近15年来主要的固载氧化剂在有机合成中的应用进行了综述。参考文献71篇。     

Ketothiolo- and Ketoselenolophosphates as Efficient Reagents in Organic Synthesis

Abstract

Novel general routes to thiolophosphates 1 and selenophosphates 2 and their application to regio- and stereoselective synthesis of olefins, functionalized olefins and heterofunctionalized dienes-1, 3 is described.     

聚离子液体的合成及应用

聚离子液体(PILs)是在重复单元上具有阴、阳离子电解质基团的聚合物。此类聚合物结合了离子液体和聚合物的一些性质,近年来在高分子化学和材料科学等领域受到广泛关注。本文将聚离子液体划分为聚阳离子型离子液体、聚阴离子型离子液体、聚两性型离子液体和共聚型离子液体四类并介绍了聚离子液体的性质及各类聚离子液体的合成。此外,本文还对聚离子液体在有机分散剂、纳米复合材料、电化学、吸附剂和分离等方面的应用进行了综述。     

烯基铝在有机合成中的应用

本文简要地综述了烯基铝及其酸根型配合物的制备以及在有机合成中的应用,包括合成烯基杂原子化合物和形成新的碳—碳键的各类反应。     

Polymeric Metal Catalysts and Reagents

This paper reviews the author's work in polymeric metal catalysts and reagents. The discussion focuses on polymeric bipyridines and on polymer-protected A1C1₃.     

N-酰基吡唑类化合物的制备及其在合成中的应用

N-酰基吡唑类化合物作为酰化试剂逐步引起了广泛关注,对其制备以及在醇解,氨解,格氏反应,瑞福尔马斯基反应等方面的用途做了探讨.     

4-取代的汉斯酯(Hantzsch Esters)作为烷基化试剂参与的有机反应

汉斯酯(Hantzsch Esters)在1881年被合成以来一直被用作还原剂参与加氢还原反应, 近年来科学家发现4-取代的汉斯酯可以发生碳碳键断裂而发生烷基迁移反应. 随后大量以4-取代的汉斯酯类化合物作为烷基化试剂的反应被报道出来, 科学家发现这类烷基化反应的历程主要是烷基自由基的迁移历程. 随着近年自由基化学的快速发展, 为这类新型烷基化试剂的应用发展提供了有力基础. 本文按照该烷基化试剂参与的反应类型分类, 进行简单介绍.     

Doped Sol-Gel Materials as Heterogeneous Reagents for Organic Synthesis

We advance the use of reactive doped sol-gel materials as heterogeneous reagents for organic-chemistry synthesis. Three approaches were demonstrated with SiO₂-based materials: Direct physical entrapment of the organic reagent; in-situ generation of an inorganic reagent within the matrix; and covalent attachment of the reagent to the matrix. With the first, entrapped p-toluenesulfonic acid facilitated the 100% yield esterification of benzoic acid with 1-pentanol, and the 100% dehydration of 1-tetralol to 1,2-dihydronaphthalene; with the second approach, a sol-gel oxidant, SiO₂/MnO₂ was used to convert benzyl alcohol to benzaldehyde and 1-tetralol to 1-tetralone; and with the third, anchored propylamine facilitated dehydrobromination reactions resulting in double-bond formation. Several other reactions with these reagents are described, and their reactivities analyzed.