Transformations based on ring-opening of gem-difluorocyclopropanes

gem-Difluorocyclopropanes are an important fluorinated class of compounds with applications in medicinal chemistry, material sciences and organic synthesis. The transformations based on their ring-opening reactions have been recognized to be useful methods for rapidly synthesizing various fluorinated organic molecules. In this digest paper, we describe these efforts and highlight their powerfully potential and applications as fluorine-containing synthons in organic chemistry.     

β-烷氧乙烯基三氟甲基酮类化合物在有机合成中的应用

β-烷氧乙烯基三氟甲基酮类化合物作为一类典型的含氟砌块, 被广泛地应用于含氟有机化合物的合成中. 综述了近年来此类含氟砌块的研究进展, 特别是在合成各种含氟杂环化合物中的应用.     

Enantioselective organocatalytic fluorination using organofluoro nucleophiles

Synthetic fluorinated compounds are enormously useful in areas such as materials, agrochemicals, pharmaceuticals and fine chemicals. While methods of electrophilic fluorination have been extensively developed to stereoselectively install fluorine atoms onto molecules, nucleophilic fluorination is a much less explored approach. Recently, several organofluoro reagents have been designed and used as nucleophiles in the asymmetric synthesis of fluorinated compounds, significantly expanding the scope of enantio-enriched fluorine-containing compounds that can be synthesised. Such organofluoro nucleophiles are particularly useful in organocatalytic transformations. In this review, recent advances in the application of organofluoro nucleophiles in organocatalysis are summarised.     

Recent advances in the synthesis of fluoroalkylated compounds using fluoroalkyl anhydrides

Fluoroalkyl-containing organic compounds have exhibited wide applications in the field of pharmaceuticals, agrochemicals and materials science due to their outstanding properties such as biological activity, metabolic stability, lipophilicity, excellent chemical and thermal stability. Therefore, various synthetic strategies have been developed for the construction of fluoroalkyl-containing compounds, using highly active fluorinating reagents and fluorinated building blocks. Recently, the use of easily available and inexpensive trifluoroacetic anhydride (TFAA) and its anhydride analogues has attracted great attention to access numerous fluoroalkyl-containing compounds through cyclization and coupling reactions. In this review, we summarized the recent advances in the synthesis of fluoroalkylated compounds using fluoroalkyl anhydrides as reagents. This review aims to provide a reference for researchers on how to develop new synthetic straregies of fluorine-containing organic compounds and achieve kilograms or even tons preparation of fluorine-containing organic compounds using fluoroalkyl anhydrides.     

Application of carbene chemistry in the synthesis of organofluorine compounds

The methods for the synthesis of fluorine-containing organic compounds are highly demanded due to the importance of those compounds in various fields. On the other hand, carbenes are in general highly reactive species, though which various transformations are possible. Carbene chemistry has been recently explored in the development of new methodologies for the synthesis of organofluorine compounds. This short report summarizes the recent advances in this area.     

New polyfluorinated organotin reagents. Stereoselective synthesis of (Z)-alpha-fluoro-beta-trifluoromethylvinylstannanes

[reaction: see text] A new methodology for the synthesis of (Z)-alpha-fluoro-beta-trifluoromethylvinylstannanes, which are useful polyfluorinated organotin reagents for the synthesis of fluorine-containing biologically active compounds, is described.     

Synthesis and optical resolution of 2-aryl-2-fluoropropionic acids, fluorinated analogues of non-steroidal anti-inflammatory drugs (NSAIDs)

We report the synthesis of optically active 2-aryl-2-fluoropropionic acids 2 as non-epimerizable mimics of 2-arylpropionic acids 1, a class of compounds which have been widely used as non-steroidal anti-inflammatory drugs (NSAIDs). This is a continuation of our research involving the design, synthesis, and evaluation of chiral fluorine-containing organic molecules as effective analogues of pharmacologically important compounds.     

含氟内酯化合物的合成方法研究进展

内酯化合物广泛存在于天然产物和具有生理活性的物质中, 因此, 内酯化合物的合成一直是人们非常关心的一个研究领域, 不仅作为天然产物的重要合成砌块, 也用来合成一些精细化工产品和医药中间体. 将氟原子或含氟基团引入到内酯化合物分子中, 可使其生理活性发生改变. 就含氟内酯化合物合成方法的研究进展进行了综述.     

Catalytic activities of modified hydrolytic enzymes in organic media : syntheses of optically active trifluoromethylated compounds

Modifications of hydrolytic enzymes by incorporation of fluorine-containing molecules have been found to improve the catalytic activity of the parent enzymes. Syntheses of optically active compounds possessing a trifluoromethyl group, via enzymatic chiral Michael addition reaction and synthesis of heterocycles, have been undertaken in organic solvents.     

Synthesis, reactions, and applications of fluorine-containing multifunctional carbon compounds

The chemistry of compounds containing a carbon atom bearing three or four different labile functional groups has received little attention. These compounds should be of considerable significance in theoretical and synthetic organic chemistry. Among the compounds with multifunctional structures, those having both carbonyl and halogen groups in addition to other heteroatom groups seem especially valuable from a synthetic viewpoint. Their potential use as probes in pure and applied synthetic chemistry has not been exploited, presumably because of structural instability and a paucity of synthetic approaches. Keeping this background in mind, we focused on the synthesis of a new class of multifunctional carbon compounds in which ester carbonyl, halogen, and other heteroatom-derived functional groups are directly attached to the central carbon atom. Fluorine was chosen as the halogen because of the inherent stability of the CF bond and because of the fundamental chemical and biological interest in fluorine-containing compounds. The synthesis, reactions, and some applications of various fluorine-containing multifunctional carbon compounds are described.     

1,3-Cyclohexadien-1-Als: Synthesis,Reactivity and Bioactivities

In synthetic organic chemistry, there are very useful basic compounds known as building blocks. One of the main reactions wherein they are applied for the synthesis of complex molecules is the Diels–Alder cycloaddition. This reaction is between a diene and a dienophile. Among the most important dienes are the cyclic dienes, as they facilitate the reaction. This review considers the synthesis and reactivity of one of these dienes with special characteristics—it is cyclic and has an electron withdrawing group. This building block has been used for the synthesis of biologically active compounds and is present in natural compounds with interesting properties.     

STUDIES ON SULFINATODEHALOGENATION:THE REACTION OF POLYFLUOROALKYL IODIDES WITH 4-PENTENOIC ACID COMPOUNDS

The radical addition of polyfluoroalkyl iodides to carbon-carbon multiple bonds is one of the most important and general methods for synthesis of a variety of fluorine-containing organic compounds.^[1] Studies in our laboratory on stulfinatodehalogenation reaction showed that sodium dithionite was a excellent initiation reagent for the addition of polyfluoroalkyl iodides, bromides and halocarbons to alkenes, alkynes and conjugated dienes effectively under mild conditions.^[2]     

Synthesis of thiophene/phenylene co‐oligomers. III . thienyl‐capped oligophenylenes

The author reports the synthesis of thienyl‐capped oligophenylenes via improved synthetic schemes. These schemes are based on either the Grignard or Suzuki coupling reaction and enable the author to obtain the target compounds at appreciably high yields. Regarding several of these compounds, their synthesis and characterization are believed to be reported for the first time. The resulting materials have been fully characterized through the nmr and ir spectroscopy. The ir analysis is particularly useful in characterizing the materials of higher molecular weight, since those materials are difficult to dissolve in organic solvents.     

合成偏氟乙烯和含氟丙烯的催化剂及应用研究进展

由于含氟烯烃在自然界易降解、对臭氧层破坏力小、对环境友好的特性,近年来在科研和工业领域得到广泛关注.偏氟乙烯（VDF）和含氟丙烯是重要的含氟烯烃,主要用于合成氟弹性体高分子功能材料的单体和含氟树脂等.我们参照偏氟乙烯的合成发展史,主要介绍了通过催化,热裂解和共裂解方法合成偏氟乙烯过程中使用的催化剂类型、工艺条件和结果对比,综述了近年来偏氟乙烯的主要合成方法,并介绍了通过直接催化氟化法合成含氟丙烯的工艺技术及其可能机理研究进展.     

碘催化的2-炔基苯胺与二硒醚的亲电环化反应

研究了碘催化的2-炔基苯胺与二硒醚的亲电环化反应. 结果表明, 在碘单质(0.2 mmol)、 2-炔基苯胺(0.2 mmol)、 二硒醚(0.1 mmol)和甲苯(2 mL)共存体系中, 反应温度为110℃时, 2-炔基苯胺与二硒醚能发生亲电环化反应, 生成相应的3-硒取代吲哚化合物, 产率为中等到良好. 该反应在无金属催化的条件下进行, 为合成官能团吲哚提供了一种新途径.     

Fluorine transfer to alkyl radicals

The development of new synthetic technologies for the selective fluorination of organic compounds has increased with the escalating importance of fluorine-containing pharmaceuticals. Traditional methods potentially applicable to drug synthesis rely on the use of ionic forms of fluorine (F(-) or F(+)). Radical methods, while potentially attractive as a complementary approach, are hindered by a paucity of safe sources of atomic fluorine (F(?)). A new approach to alkyl fluorination has been developed that utilizes the reagent N-fluorobenzenesulfonimide as a fluorine transfer agent to alkyl radicals. This approach is successful for a broad range of alkyl radicals, including primary, secondary, tertiary, benzylic, and heteroatom-stabilized radicals. Furthermore, calculations reveal that fluorine-containing ionic reagents are likely candidates for further expansion of this approach to polar reaction media. The use of these reagents in alkyl radical fluorination has the potential to enable powerful new transformations that otherwise would take multiple synthetic steps.     

Ring-Opening Fluorination of Carbo/Heterocycles and Aromatics: Construction of Complex and Diverse Fluorine-Containing Molecules

Fluorine-containing molecules have attracted much attention in medicinal, agrochemical, and materials sciences because they offer unique physical and biological properties. Therefore, many efficient fluorination reactions have been developed over the years. Recent advancements in fluorination chemistry have expanded the range of substrates, and regioselectivity/stereoselectivity control has also been achieved. Ring-opening fluorination is an efficient method to construct complex fluorine-containing molecules with diversity, starting from simple cyclic compounds. This review aims to summarize developments in ring-opening fluorination, particularly with larger-sized cyclic compounds. Fluorine introduction and bond cleavage of cyclic compounds such as carbocycles, heterocycles, and aromatics provide efficient access to fluorine-containing compounds that are difficult to be synthesized by conventional methods.     

Advances in the preparation of organofluorine compounds involving iodine and/or iodo-compounds

The intriguing properties of iodine have drawn the attention of organic chemists. In this paper, we will describe the recent development of stereo- and/or regioselective synthesis of fluorine-containing organic compounds employing hypervalent iodine fluorides such as ArIF₂ (1), IF₅ (22), and (E)-2-fluoro-alk-1-enyl-4-aryl iodonium salts R(F)C=C(H)IF-Ar (12). The electrochemical fluorination procedures involving iodo-compounds will also be presented to prepare fluoro-organic compounds.     

Adamantyl-containing fluorinated 1,3-diketones

A convenient one-step procedure has been developed for the synthesis of fluorine-containing 2-(adamant-l-yl)-1,3-diketones by reaction of fluorinated 1,3-diketones with 1,3-dehydroadamantane. The products can be used as starting compounds for the preparation of new fluorinated adamantyl-containing heterocyclic compounds.     

Synthesis of fluorinated amino acid derivatives through late-stage deoxyfluorinations

Fluorine chemistry has represented a hot topic in drug research over the last decade. Because of their pharmaceutical potential, fluorine-containing amino acids and related derivatives have acquired high importance among medicinal chemists. Therefore their synthesis and the development of various synthetic methods for these types of molecular scaffolds have gained increasing interest in synthetic organic chemistry. The current review focuses on synthetic protocols towards fluorine-containing amino acid derivatives through late-stage fluorination with various nucleophilic reagents, describing the access of various open-chain and cyclic α-, β-, γ-amino acid derivatives.