Field Of Synthetic Organic Chemistry Research Articles

ChemInform Abstract: Use of Sulfur Fragments for the Synthesis of Nitrogen Heterocycles

AbstractReview: 178 refs.

ChemInform Abstract: Synthesis without Metals

AbstractReview: 174 refs.

β-Oxodithioesters: a new frontier for diverse heterocyclic architectures

Utilization of the fascinating properties of β-oxodithioesters as building blocks in heterocyclic frameworks was started a few decades ago. Its similarity and dissimilarity with β-ketoesters in terms of its synthesis or as a substrate towards synthesis makes it an interesting and emerging field of synthetic organic chemistry. Tuning of catalysts and counter substrates towards selective utilization of its multiple reacting sites was summarized in the following discussion. A diverse range of monocyclic and polycyclic heterocycles with several different heteroatoms is plotted in an easy and reader friendly manner.

ChemInform Abstract: Development of New Catalytic Reactions Based on Activation of Hydrocarbon Functional Groups by Lewis Acids

AbstractReview: ca. 50 refs.

ChemInform Abstract: Microwave‐Assisted C—C Bond‐Forming Cross‐Coupling Reactions: An Overview

AbstractReview: ca. 70 refs.

Evolution of microwave irradiation and its application in green chemistry and biosciences

Microwave-assisted organic reactions have been applied as an effective technique in organic synthesis. Microwave irradiation often leads to shorter reaction times, increased yields, easier workup, matches with green chemistry protocols, and can enhance the region and stereo selectivity of reactions. In fact, the high usefulness of microwave-assisted synthesis encouraged us to increase the efficiency of several organic transformations and synthesis. High-speed microwave-assisted chemistry has attracted a considerable amount of attention in recent years and has been applied successfully in various fields of synthetic organic chemistry, proteins, peptides, drug discovery, and green chemistry. The various roles of microwave-assisted organic chemistry in green and sustainable chemistry are discussed, beginning with the strategies, technologies, and methods that were employed routinely at the time of the first reports of microwave applications. Microwave processing has several advantages over conventional sintering/heating, such as the reduction in cycle time, energy efficiency, eco-friendliness, and providing finer microstructures, leading to improved mechanical properties. Herein, we also describe the evolution of the microwave and some early applications of microwave assistance in the biomolecular sciences and treatment of solid malignant tumors.

Microwave-assisted C–C bond forming cross-coupling reactions: an overview

Among the fundamental transformations in the field of synthetic organic chemistry, transition-metal-catalyzed reactions provide some of the most attractive methodologies for the formation of C-C and C-heteroatom bonds. As a result, the application of these reactions has increased tremendously during the past decades and cross-coupling reactions became a standard tool for synthetic organic chemists. Furthermore, a tremendous upsurge in the development of new catalysts and ligands, as well as an increased understanding of the mechanisms, has contributed substantially to recent advances in the field. Traditionally, organic reactions are carried out by conductive heating with an external heat source (for example, an oil bath). However, the application of microwave irradiation is a steadily gaining field as an alternative heating mode since its dawn at the end of the last century. This tutorial review focuses on some of the recent developments in the field of cross-coupling reactions assisted by microwave irradiation.

ルイス酸による炭化水素官能基の活性化を基軸とする新触媒反応の開発

Over a long period of time, in the field of synthetic organic chemistry, Lewis acids have been used mainly as activators for heteroatom-containing functional groups such as carbonyls, imines and halides. In contrast to the traditional approach utilizing such Lewis acid chemistry, we have been focusing on developing new catalytic reactions on the basis of activation of hydrocarbon functional groups by Lewis acids. In order to activate effectively the hydrocarbon functional groups classified into C≡C, C=C, C−C and C−H, an appropriate choice of a Lewis acid catalyst is a crucial aspect. Herein, I disclose our recent achievements based on the Lewis acid-activated hydrocarbon functional groups.

세미카바존의 전기적 산화에 의한 2-Amino-5-Substituted-1,3,4-Oxadiazoles 합성

The synthesis of 2-amino-5-substituted-1,3,4-oxadiazoles 4 were carried out from the electrooxidation of semicarbazone 3 at the platinum electrode under controlled potential electrolysis in an undivided cell. This is an environmentally benign method in the field of synthetic organic chemistry. The non-aqueous solvents acetic acid and acetonitrile and a supporting electrolyte lithium perchlorate were used for the electrolysis in the electrooxidation. The products were structurally charecterised by IR, -NMR, -NMR and elemental analysis.

Applications of Zirconium(IV) Chloride in Organic Synthesis

Zirconium(IV) chloride is used extensively in organic synthesis as an ideal Lewis acid since it is an efficient, stable, inexpensive, environmentally friendly and convenient catalyst for the preparation of useful synthetic intermediates and for use in key steps of natural products synthesis. This review is broadly divided into four sections based on zirconium(IV) chloride mediated reactions (1) carbon-carbon bond-formation reactions, (2) protection and deprotection chemistry, (3) reduction reactions, and (4) other applications. This review is an attempt to cover the important advances in the field of synthetic organic chemistry that have been carried out to date. 1 Introduction 2 Carbon-Carbon Bond-Formation Reactions 3 Protections and Deprotections 4 Reduction Reactions 5 Miscellaneous Reactions 6 Zirconium-Based Reagents and Complexes 7 Conclusions

Synthesis and Functionalization of Indoles through Rhodium-Catalyzed Reactions

Indoles are abundant in nature, and exhibit important biological properties such as anti-inflammatory, antihypertensive, dopaminergic, antineoplastic, anticonvulsant, analgesic, sedative, muscle relaxant, and antimicrobial activities. Synthesis, and functionalization of pharmacologically active indoles continue to receive considerable attention in the field of synthetic organic chemistry. Recent advances toward synthesis of natural, and unnatural indoles have been accelerated by transition metal catalysts, and in the context rhodium has proven to be an extremely useful metal due to its ability to catalyze an array of synthetic transformations with quite often-unique selectivity. This review describes the formation of indoles via rhodium catalyzed C-H, and X-H insertion (X = N, O, and S), cycloaddition, hydroformylation, bimetallic, and asymmetric hydrogenation reactions. Use of solid phase chemistry in rhodium catalyzed indole synthesis has also been discussed in the article. Keywords: Indoles, Rhodium(II)-catalyst, Insertion, Cycloaddition, Hydrogination, Solid-phase

Recent advances in synthetic micro reaction technology

Although in its infancy, the field of micro reaction technology is growing rapidly, with many research groups investigating the practical advantages associated with reaction miniaturisation. With this in mind, the following Feature Article aims to provide an overview of the progress made in the past decade, paying particular attention to the field of synthetic organic chemistry.

Towards Liquid Crystal Synthesis Using High Throughput and Micro Reactor Technologies

AbstractFor Abstract see ChemInform Abstract in Full Text.

Towards liquid crystal synthesis using high throughput and micro reactor technologies

While many areas of chemistry, including pharmaceuticals, materials and fine chemicals, have embraced high throughput technologies, the field of liquid crystals has not. This is surprising, as the ability to screen large numbers of homologues and analogues in a short space of time is one of the rate-limiting steps in the development of new liquid crystalline materials. Here, the role of chemical micro reactors (CMRs) in the field of synthetic organic chemistry will be reviewed in light of their potential application in liquid crystal synthesis.

Waste-free solid-state syntheses with quantitative yield

Unexpected organic solid-state reactions in the gas–solid and stoichiometric solid–solid versions are highly promising new tools for solvent-free sustainable synthesis and production if they occur with 100% yield. Costly workup is obsolete, no wastes are formed and resources and energy saved. More than 500 published 100%-yield, solid-state reactions in 25 reaction types cover virtually all fields of synthetic organic chemistry. Atomic force microscopy (AFM) reveals that solid-state reactions require long-range molecular movements and are strictly and sensibly guided by the crystal packing. Three steps govern the issue: phase rebuilding, phase transformation, and crystal disintegration (detachment). If one of these fails, or if liquid phases are not avoided, the reaction will usually not run to completion. Repeated creation of fresh contacts of crystallites is essential in solid–solid reactions. New, otherwise inaccessible and highly reactive products are most easily obtained. Cooling below eutectic temperatures, but also thermal activation above room temperature, may be necessary. Liquids may be solidified by cooling or inclusion complexation. Typical single-step, multi-step and cascade reactions have been performed with 100% yield using commonly available starting materials in various fields. Upscaling to the kilogram scale has been achieved under various conditions. Further upscaling to technical size productions seems possible.

ChemInform Abstract: Applications of Carbene Complexes Toward Organic Synthesis

Abstract The article highlights advances in the discovery and development of reaction processes utilizing metal–carbene complexes which are useful in the field of synthetic organic chemistry. Emphasis is on reaction processes which result in the formation of carbon–carbon bonds in a reliable and efficient manner. Examples utilizing these reaction processes for the synthesis of biologically-important molecules has been noted wherever appropriate.

Reaction between Phenols and Isoprene under Zeolite Catalysis. Highly Selective Synthesis of Chromans and o-Isopentenylphenols

Chromans 3 and o-isopentenylphenols 4 are synthesi- zed in satisfactory to good yields and selectivities by the reaction of phenols and isoprene in the presence of the commercially available acid faujasite zeolite HSZ-360. The preparation of fine chemicals following environmen- tally friendly strategies represents a challenging goal in the field of synthetic organic chemistry. 1 In the last ten years this approach has had a great development, mainly due to the use of solid acids such as clays and zeolites, (up to that time nearly exclusively employed in petrochemical processes). 2 It is now well stated that the use of these het- erogeneous catalysts represents the best answer both to the new environmental legislation and to the old chemis- try requirements: the processes they promote produce the minimum of pollution and show good 3 yields frequently accompanied by excellent selectivities. As part of a programme designed to develop new selective and preparatively useful methods based on the use of solid acids as catalysts for the preparation of fine chemicals, previous investigations of our laboratory have described the synthesis of 2H-1-benzopyrans from phenols and a- alkynols using a commercial HY-zeolite in typically a het- erogeneously catalyzed process. 4 The a-alkynols, first dehydrate into the corresponding enynes which subsequently react with phenols in a regio- selective way to form 2H-1-benzopyrans; in all cases the sole products arise from interaction of the phenol oxygen with the olefinic double bond and the ortho carbon of the phenol ring with the acetylenic framework of the enyne in- termediate. On the basis of these results we investigated the reaction of isoprene with phenols to produce chromans (3,4-dihydro-2H-1-benzopyrans) over solid acid catalysts. The synthesis of chromans or o-isopentenylphenols (2-(3- methylbut-2-enyl)phenols), 5 important classes of natural and biologically active compounds, has been extensively studied by many researchers, but it's chemo- and regiose- lective control is only achieved by using sophisticated cat- alytic systems such as conveniently prepared acid-base combinations 6 or transition metal complexes, 7 whereas the simple acid catalysis is described to result in less se-

A derivation of the Masamune rule of multiplicativity in double asymmetric induction

The ability to prepare one diastereomeric or enantiomeric isomer in excess in a given chemical transformation where a stereoisomeric distribution of products is possible is currently one of the most highly sought goals in the field of synthetic organic chemistry.

Microbial and Enzymatic Processes for the Production of Biologically and Chemically Useful Compounds [New Synthetic Methods (69)

AbstractIn recent years, the most significant development in the field of synthetic organic chemistry has been the application of biological systems to chemical reactions. Reactions catalyzed by enzymes and enzyme systems display far greater specificities than more conventional organic reactions. Biological and/or enzymatic syntheses and transformations, that is, “microbial transformations,” have great potential. Some of these reactions have already been shown to have useful applications in the fields of synthetic organic chemistry and biotechnology. This article reviews the current status of the rapidly developing field of microbial transformation, the methodology, available technological procedures, and fields of application being described especially in relation to conventional organic synthesis methods.

金属クラスターを用いる合成化学反応

Recent developments concerning homogeneous catalysts stimulate new interest in the field of synthetic organic chemistry. In particular, metal cluster as homogeneous catalysts offer not only better and more selective catalyst for the synthetic reactions, but also useful models in the study of chemisorption and heterogeneous catalysis. Metal cluster compounds contain three or more metals bonded to each other forming triangular, tetrahedral, octahedral and other polyhedral molecular structures. Application of metal clusters as catalyst is especially welcome in these days when the chemical industry should seek ways to conserve energy and resources.In this context, the following synthetic reactions by means of metal clusters are introduced in this review : hydrocarbons and alcohols from synthetic gas, oxidation reaction, dehydrogenation and isomerization, hydrogenation (especially by Ni-isonitrile cluster), dimerization, hydroformylation, carbonylation, Reppe reaction, water gas shift reaction, anchored metal cluster catalysis, peculiar cluster compounds and the ligand mobility within clusters.