二芳基脯氨醇衍生物催化的硝基烯参与的多组分不对称串联合成研究进展

硝基烯是一类重要的有机合成子,以硝基烯烃为原料,二芳基脯氨醇衍生物催化的多组分不对称串联反应是构建复杂手性化合物的重要方法,被广泛应用于有机合成和新药开发领域.根据构建的目标化合物类型,较全面地总结了基于二芳基脯氨醇衍生物催化、硝基烯为合成子的多组分不对称串联反应的合成研究,从反应的催化剂体系、反应机理、实验结果、反应优点、存在的问题和局限性等方面进行介绍,并对今后的发展做出展望.     

计量合成学的产生与发展

对计量合成学的产生与发展及其研究与应用进行了综论，强调了计量化学在合成中的应用，集中在开发有机合成反应的决策及战术方面，通过试验设计对反应体系深入探索及通过自适应建模对试验条件的系统优化和通过综合评价对合成产物的全面考察，将有机反应开发为合成方法，参考文献３５篇。     

Development of optimised synthesis of 4-amino-N-(4-carbamoylphenyl)benzamide for industrial application

An efficient two-step synthetic route for preparation of the important Pigment Yellow 181 intermediate 4-amino-N-(4-carbamoylphenyl)benzamide is described. The synthetic pathway reflects requirements that are important for industrial applications. Optimisation of the reaction steps was performed to improve yields and procedures. The overall yield was higher than 78 %.     

Synthesis and reactions of sulfur-substituted α,β-unsaturated δ- and γ-lactones

A new synthetic method for the preparation of sulfur-substituted α,β-unsaturated δ- and γ-lactones has been developed by reaction of the allylic bromides of 5,6-dihydro-2-pyridinones with NaOH in refluxing MeOH or t-BuOH. The substituents at C5 and C6 of these substrates are very important for the success of this reaction. Some synthetic transformations of the α,β-unsaturated δ-lactones have also been carried out.     

Light- and Manganese-Initiated Borylation of Aryl Diazonium Salts: Mechanistic Insight on the Ultrafast Time-Scale Revealed by Time-Resolved Spectroscopic Analysis

Manganese-mediated borylation of aryl/heteroaryl diazonium salts emerges as a general and versatile synthetic methodology for the synthesis of the corresponding boronate esters. The reaction proved an ideal testing ground for delineating the Mn species responsible for the photochemical reaction processes, that is, involving either Mn radical or Mn cationic species, which is dependent on the presence of a suitably strong oxidant. Our findings are important for a plethora of processes employing Mn-containing carbonyl species as initiators and/or catalysts, which have considerable potential in synthetic applications.     

Gold in total synthesis: alkynes as carbonyl surrogates

Fields of gold: Recent developments in the field of gold catalysis, using an alkyne as a carbonyl equivalent is becoming an important chemical transformation, thus providing flexibility in synthetic planning of complex and sensitive natural products. Understanding of the reaction and new catalyst designs are providing new conditions that are amenable for late-stage synthetic intermediates.     

NH-1,2,3-三唑合成进展

NH-1,2,3-三唑是一类具有重要生理活性的含氮杂环化合物, 是用途广泛的药物中间体. 通过N-烃基化反应, NH-1,2,3-三唑还可以区域选择性的合成各种2-取代-1,2,3-三唑类化合物, 因此是有价值的有机合成中间体. 鉴于NH-1,2,3-三唑在有机合成化学和药物化学中的潜在应用价值, 结合本课题组的研究工作, 对于NH-1,2,3-三唑的主要合成方法, 尤其是近十年来的合成研究进展进行了回顾和展望. 对一些典型的反应机理研究也进行了综述.     

Improved synthesis of functionalized 2,2'-bipyrroles

A series of 2,2'-bipyrroles has been efficiently synthesized using an improved synthetic approach based on Pd(0)-catalyzed homocoupling of various 2-iodopyrroles. This new synthetic approach takes place at room temperature and in the presence of water. Functional groups such as formyl, ester, and nitrile are able to survive these reaction conditions. Solvents are found to play an important role in this reaction.     

Yttrium-catalyzed heterocyclic formation via aerobic oxygenation: A green approach to benzothiazoles

The YCl₃-catalyzed aerobic oxidative cyclization reaction for the synthesis of benzothiazoles has been developed.This method provides a practical,effective and green synthetic approach to benzothiazoles which are important units in many biologically active compounds.     

The nitrosocarbonyl hetero-Diels-Alder reaction as a useful tool for organic syntheses

Organic transformations that result in the formation of multiple covalent bonds within the same reaction are some of the most powerful tools in synthetic organic chemistry. Nitrosocarbonyl hetero-Diels-Alder (HDA) reactions allow for the simultaneous stereospecific introduction of carbon-nitrogen and carbon-oxygen bonds in one synthetic step, and provide direct access to 3,6-dihydro-1,2-oxazines. This Review describes the development of the nitrosocarbonyl HDA reaction and the utility of the resulting oxazine ring in the synthesis of a variety of important, biologically active molecules.     

Review of the aldol reaction

Aldol condensation is an important synthetic method widely used in organic synthesis. Development of catalytic methods that avoids the production of stoichiometric by-products while maintaining high levels of control available from stoichiometric processes provides an atom-economical alternative for these important transformations. Indeed, numerous catalysts for the aldol reaction have been reported in recent years, including enzymes, catalytic antibodies, organometals, organocatalysts, and small molecules. The direct aldol reaction is the most important reaction employed by synthetic chemists and is common in nature. Recently, various Lewis acids have been examined as catalysts for aldol reactions, but aldol condensation in a micellar medium has not been studied in detail so far. Because of stronger environmental concerns, organic reactions in green media, especially in water, have attracted more attention. It is believed that micelles act as nano reactors to enhance the reaction rates and give very good to excellent yields of end products.     

A modified Prins reaction for the facile synthesis of structurally diverse substituted 5-(2-hydroxyethyl)-3,3-dihydrofurane-2(3H)-ones

Furanones are important synthetic intermediates commonly found in natural products, receptor ligands, and drug molecules. Unacceptable yields of substituted furanones obtained using a previously reported Prins reaction led to the development of a modified approach. Readily prepared substituted allylic esters were reacted under Prins reaction conditions catalyzed by a protic acid to provide structurally diverse substituted furanones in modest to good yields. The reaction goes through a protected caprolactone intermediate that was isolated and characterized for selected compounds. The approach supplies an efficient, versatile, and higher yield method for the synthesis of these important heterocyclic intermediates.     

Catalytic Double Stereoinduction in Asymmetric Allylic Alkylation of Oxindoles

A highly regio‐, diastereo‐, and enantioselective allylic alkylation reaction of 3‐monosubstituted oxindoles catalyzed by molybdenum is described. The reaction is affected by the electronic and steric variations of the nucleophile. The use of appropriate N‐protecting group is particularly important for achieving high regio‐ and diastereoselectivity. Products from this reaction, containing vicinal quaternary‐tertiary stereogenic centers, are valuable synthetic intermediates and should find utility in alkaloid synthesis.     

缩醛化反应研究进展

缩醛化合物是非常重要的有机合成中间体. 介绍了以醛、烯烃为原料合成缩醛化合物的方法以及这两类合成方法研究的最新进展, 尤其介绍了在合成缩醛化合物方面开发的新型绿色催化剂、绿色新技术与绿色工艺.     

Biocatalytic and biomimetic aminolysis reactions: useful tools for selective transformations on polyfunctional substrates

Aminolysis is a deeply studied reaction, but the development of new catalysts for this process is still an emerging area of organic and bioorganic chemistry. Two different approaches are reviewed in this article: the biomimetic de novo designed synthetic catalysts and the use of natural enzymes. Brief mechanistic considerations are discussed. Some important aspects like chemo-, regio- and stereoselectivity towards the substrates are highlighted on selected examples with synthetic applications.     

Preparation of unsubstituted dipyridine‐dibarbituric acid ylide through dimerization of pyridin‐2‐ylmethylenepyrimidinetrione as a reactive intermediate

Preparation of 5,5′‐(pyridin‐2‐ylmethylene)dipyrimidinetrione from barbituric acid and 2‐pyridinecarbox‐aldehyde in any polar solvent is a straightforward synthetic procedure, while preparation of the dipyridine‐dibarbituric acid ylide from the same starting materials is sensitive to the reaction media, pH, and temperature. For both products, the formation of the reactive intermediate 2‐pyridin‐2‐ylmethylenepyrimidinetrione is certain and this intermediate is a cross road for the reaction to be directed in one way or other. The experimental evidence for the formation of this important intermediate, as well as synthetic procedures for the preparation of both condensation products are presented.     

Umpolung strategy for the synthesis of 2-deoxy-C-aryl glycosides: a serendipitous,efficient route for C-furanoside analogues

[reaction: see text] 2-Deoxy-C-aryl glycosides are potential synthetic targets as they form a very vital moiety of several biologically active natural products. This paper describes a synthetic route using an umpolung strategy, which has not been explored till date. Our synthetic endeavor led to a versatile intermediate aryl ketone 10, which has paved the way for two important classes of C-glycosides, viz., C-alkyl furanosides 12 and methyl 2-deoxy-C-aryl pyranosides 14.     

Y(OTf)3-catalyzed heterocyclic formation via aerobic oxygenation: An approach to dihydro quinazolinones and quinazolinones

The Y(OTf)₃-catalyzed aerobic oxidative cyclization reaction for the selective synthesis of dihydroquinazolinones and quinazolinones has been developed. This method provides a practical, effective and green synthetic approach to dihydroquinazolinones and quinazolinones which both are important units in many biologically active compounds.     

The Dowd–Beckwith Reaction: History,Strategies, and Synthetic Potential

Ring-expansion strategies are valuable synthetic tools that take benefit of existing ring structures and evade the unfavorable enthalpic-and entropic effects that arise with end-to-end cyclizations. One potentially important class of such reactions is the Dowd–Beckwith reaction, the ring-expansion of ketones via alkoxy radicals. The exciting advancement in this research area is starting to show its potential, as demonstrated by applying this methodology in strategy-level bond formation to synthesize complex natural products. This Review aims to provide the first comprehensive survey of the development of the Dowd–Beckwith reaction spanning three decades from the initial report to the present day, thus providing the readers with great detail about the contributions of this reaction to organic synthesis. We hope that this review will further disclose the salient features of the Dowd–Beckwith reaction for synthetic applications and encourage the development of new, more advanced applications.     

Palladium(0)‐Catalyzed Heck Reaction/CH Activation/Amination Sequence with Diaziridinone: A Facile Approach to Indolines

Indolines are important moieties present in various biologically significant molecules and have attracted considerable attention in synthetic chemistry. This paper describes a Heck reaction/C? H activation/amination sequence for forming indolines using di‐tert‐butyldiaziridinone. The reaction process likely proceeds via a pallada(II)cycle, which is converted into an indoline by oxidative addition to the diaziridinone and two subsequent C? N bond formations.