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1.
秦思凝 《有机化学》2023,(11):3761-3783
含硫化合物在天然产物、药物、农药和材料中广泛存在,具有多种生物活性或独特功能.C—S偶联反应是合成含硫化合物的重要方法,是有机合成领域的研究热点之一.随着对催化剂的深入开发和对含硫偶联反应物的不断扩展,近年来涌现出大量的C—S偶联反应方法,为含硫化合物的合成提供了便利.芳香卤代烃是合成含硫化合物的主要底物,通过设计不同的反应体系和含硫偶联反应物进行C—S偶联反应,能够高效地合成硫酚、硫醚、二硫醚和砜等含硫化合物.按照不同种类的含硫偶联反应物类型和催化剂种类(钯、铜和镍等)进行分类,综述了近年来以芳香卤代烃为底物的C—S偶联反应,并对代表性反应的机理做了简要说明和比较.此外,还对这一领域目前存在的问题和局限性进行简要分析,并对未来发展方向提出展望.  相似文献   

2.
含硫有机化合物广泛应用于有机合成、医药、农药和功能材料等领域中,发展绿色、温和、高效的有机硫化合物的合成方法具有重要意义.作为理想的绿色氧化剂,氧气可直接引发一些含硫化合物为硫中心自由基,其参与的反应为构建S—S、P—S和C—S键提供了新途径.该方法可避免使用毒性试剂、过渡金属和强氧化剂等,而且反应条件温和.依据反应类型的不同,对近年来氧气引发的硫中心自由基参与的构建S—S、P—S和C—S键研究进展进行介绍.  相似文献   

3.
综述了近年来利用磷-氢化合物与简单易得试剂交叉偶联合成有机磷化合物的研究进展.主要包括利用末端炔烃与磷-氢化合物通过C—H/P—H交叉偶联合成炔基膦化合物,利用简单易得的含氧、含硫或含氮有机化合物与磷-氢化合物交叉偶联构建sp~2/sp~3-C—P键或P—Z键,并对部分反应的机理进行扼要总结.  相似文献   

4.
硫转移催化剂研究(I): 组成、结构与吸硫活性关系   总被引:8,自引:0,他引:8  
在流化催化裂化炼制汽油时,进料油中含有一定量的有机硫化合物,其中一部分硫沉积在焦炭上并在再生器中转化为SO。(SO。+S0a).如果催化裂化(FC)年处理量按1000万吨计算,估计每年约有3万吨SO。进入大气中.如不处理直接排放必将严重污染大气环境.国外已开展对FCC再生烟中SO。控制的研究,但多以HZ作为还原剂,故须外加引入装置[‘,‘].本文报告的是用硫转移催化剂催化税除SO。;即根据FCC工艺条件,结合FCC催化剂所处的实际环境,在FCC催化剂中MA质量分数为0.01-0.03的含稀土的铝侯尖晶石基的硫转移催化剂,使它…  相似文献   

5.
魏芳  余鑫  肖强 《有机化学》2023,(4):1365-1385
有机叠氮化合物在天然产物全合成、药物化学以及材料化学等领域有广泛的应用.叠氮基团在反应过程中倾向于脱除氮气,转化为多种多样的含氮杂环以及氨基类化合物,但在许多天然产物全合成的关键步骤中,都需要保留叠氮基团.总结了近二十年有机叠氮化合物参与的反应中C—N3键保留的反应类型,主要包括环加成反应、与不饱和键的加成、Winstein重排和1,2-叠氮迁移等.  相似文献   

6.
根据流化催化裂化(FCC)再生过程中NOx的生成机理和特点,FCC再生过程中NOx控制技术主要包括FCC原料预处理与改变工艺参数、脱NOx添加剂和FCC再生烟气脱硝3种。本文综合分析了FCC再生过程NOx控制技术原理、工艺流程及特点,在现有技术的基础上,以"以废治污"为指导思想,提出了利用粉煤灰制备脱硝催化剂,构建了原位催化还原与烟气返回耦合降低FCC再生过程NOx排放新工艺,开辟了粉煤灰资源化利用新途径,为开发FCC再生过程中NOx污染控制技术提供科学理论指导。  相似文献   

7.
随着优质煤资源的消耗,高硫煤的清洁高效转化备受关注,尤其是高硫炼焦煤中有机硫的调控至关重要。煤热解过程中,有机硫的变迁始于煤大分子结构中C–S键的断裂和含硫自由基的稳定,活性氢/氧是影响其转化赋存形态的重要因素。研究表明,煤在富氢/氧氛围下热解或与生物质、含氧有机物共热解的体系中,含有的活性氢/氧可弱化有机硫的C–S键,促进其断裂并及时结合生成的含硫自由基,促进煤中硫分向气相变迁,减少了含硫自由基与煤基质的二次反应。同时,高挥发分煤与高硫煤共热解过程中,相对丰富的挥发分中的活性氢/氧也会影响高硫煤中有机硫的变迁,降低焦炭中的硫含量,这为煤中硫分定向调控提供了理论基础。  相似文献   

8.
亚磺酸钠(RSO_2Na)性质稳定、合成简单、价格低廉,在有机合成化学领域被广泛应用.综述了最近五年来亚磺酸钠在合成含硫化合物反应中的最新研究进展.分别叙述了其在有机反应中构建S—C键、S—杂键(S—S键、S—N键以及S—P键)的底物适应范围和反应机理,为今后亚磺酸钠的在有机合成中的应用提供参考.  相似文献   

9.
含硫化合物在医药、农业、天然产物和有机材料等方面有广泛的应用,因而引起了科研人员极大的兴趣,开发高效、绿色的含硫化合物的构建和转化方法具有重要意义.近年来,稳定、低毒的芳基二硫醚类化合物作为刺激性强、毒性大的硫醇类化合物的理想替代物,为各种含硫化合物的构建开辟了一条新的途径.从光催化、非金属参与和过渡金属催化三个方面分类综述了芳基二硫醚作为自由基硫试剂构建C—S键的研究进展.  相似文献   

10.
有机氰化物是一种重要的合成中间体,在药物、农药、染料和活性物质中都有应用.使用廉价、简单、低毒的氰基化合物在过渡金属的催化下通过C—CN键断裂生成复杂的氰化物是合成有机氰化物的重要手段之一.综述了不同过渡金属(如Ni,Pd,Rh,Cu,Ru,Fe,Mo,Co等)催化不同种类的氰基化合物C—CN键断裂的最新研究进展,如含C(sp1)—CN键化合物、C(sp2)—CN键化合物以及C(sp3)—CN键化合物,并对有关的反应机理及C—CN键断裂机理的进展进行了探讨.  相似文献   

11.
Organic integrated circuits are undergoing rapid development with the extensive research on organic semiconducting materials and the performance improvement of organic field-effect transistors. Organic integrated circuits not only cover all the major circuit types, their complexity, degree of integration, and performance have also been improved in recent years. In this review, recent advances in the design and fabrication of integrated circuits based on organic field-effect transistors are reported. The circuits are categorized into digital and analog, which are discussed in detail centering on the structure, fabrication process, and performance. In addition, progress in the modeling and simulation of organic integrated circuits are discussed as well, as they are key issues for the future development of organic electronics.  相似文献   

12.
Another brick in the wall: Porous ternary cocrystals were prepared by chiral recognition between organic cage modules. One module, CC1, is ordered on 50?% of the lattice positions with respect to two other modules, CC3 and CC4, that are disordered across the other 50?% of sites (see picture). There is a linear relationship between relative module composition and the cocrystal lattice parameters.  相似文献   

13.
A chiral covalent organic framework was synthesized, characterized, and incorporated into organic polymer monolithic capillary columns to provide chiral stationary phases for enantioseparations. The prepared monolithic capillary columns were characterized by scanning electron microscopy and elemental analysis. To obtain better enantioseparations, the columns’ preparation conditions, and enantioseparation conditions were optimized. Baseline resolutions of several chiral compounds were obtained with good reproducibility and stability. Furthermore, the mechanism of chiral recognition was investigated using molecular docking with AutoDock. Docking results showed that the enantioselectivity factor rather than resolution is correlated with the binding free energy difference between enantiomers with the chiral covalent organic framework. And abundant acetoxy and nitrile groups as well as benzene rings in the chiral covalent organic framework are responsible for the enantioseparation ability of the chiral monolithic capillary columns.  相似文献   

14.
有机微波化学研究进展   总被引:42,自引:0,他引:42  
本文综述了近几年来微波技术在有机合成方面的研究和应用进展。初步探讨了微波催化有机反应的作用机理, 并展望了有机微波化学的发展前景。  相似文献   

15.
The functionalization of porous metal–organic frameworks (Cu3(BTC)2) was achieved by incorporating Keggin-type polyoxometalates (POMs), and further optimized via alkali metal ion-exchange. In addition to thermal gravimetric analysis, IR, single-crystal X-ray diffraction, and powder X-ray diffraction, the adsorption properties were characterized by N2 and volatile organic compounds (VOCs) adsorption measurements, including short-chain alcohols (C<4), cyclohexane, benzene, and toluene. The adsorption enthalpies estimated by the modified Clausius–Clapeyron equation provided insight into the impact of POMs and alkali metal cations on the adsorption of VOCs. The introduction of POMs not only improved the stability, but also brought the increase of adsorption capacity by strengthening the interaction with gas molecules. Furthermore, the exchanged alkali metal cations acted as active sites to interact with adsorbates and enhanced the adsorption of VOCs.  相似文献   

16.
Several hollow porous organic polymers were conveniently fabricated by poly‐condensation of tetraphenyl porphyrin (TPP), tetrabiphenyl porphyrin (TBPP), or triphenylbenzene (TPB), with nano‐sized ZnO particles as template and AlCl3 as catalyst. The hollow polymers exhibit much enhanced adsorption capacity for organic dyes in aqueous solution relative to the pristine polymers. Particularly, the hollow polymer based on TBPP (h‐COP‐P) displays high adsorption capacity (460 mg/g within 500 min) as well as good recycling performance toward Rhodamine B. This capacity is about three times larger than that of corresponding pristine POPs (COP‐P) and is even comparable with the best performed organic polymers reports to date, which is ascribed to its unique hydrophobic hollow structure. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1329–1337  相似文献   

17.
超声在有机反应中的应用   总被引:10,自引:1,他引:10  
介绍了超声化学的原理和实验室常用的超声设备。评述了超声在均、多相有机 反应中的应用。超声在均、多相反应中除可以提高反应速率,有时也可以改变反应 路线。在相转移催化反应体系中,超声能够取代相转移催化剂,使反应顺利进行。  相似文献   

18.
Among various two-dimensional (2D) materials, organic 2D polymers have attracted much attention, owing to their specific properties, such as lightweight, good flexibility, adjustable structure, and high adaptability. In recent years, more and more scientists have devoted to the research on their structural design, synthesis, characterization, and potential properties. However, in contrast to traditional one-dimensional (1D) and three-dimensional (3D) network macromolecules, the synthesis of 2D structures presents a challenge to polymer chemists, because polymerization usually takes place in a spatially random manner in solution-phase synthesis. In this review, we will focus on the synthesis methods of organic 2D materials, which have played a pivotal role since the beginning of the development of this field. We will highlight the representative examples according to the different types of polymers, including supramolecular organic 2D layers and covalent organic 2D polymers, and identify possible future research directions.  相似文献   

19.
To better understand the cycling of marine dissolved organic matter, analytical methods are required allowing for data on dissolved organic nitrogen and phosphorus (DON and DOP) to be acquired with high analytical performance. The coverage of documented DON and DOP analytical performance is very limited; instead analytical data are mostly available for total dissolved N and P (TDN and TDP) analyses. This substitution overestimates analytical performance for DON and DOP measurements due to the cumulative effect of Standard Deviation applied for detection limit and precision evaluations. The little available data obtained by photolytic, chemical, a combination of both, and high temperature combustion methods indicate that current detection limit is 0.30 µM for DON and 0.010 µM for DOP. Precision for both analytes, in general, is ≤4.5%. The data on accuracy is scarce despite availability of Reference Materials for TDN and NO3? + NO2? analyses, and for the TDN measurement is <5%; even fewer data exist for TDP due to a lack of reference material for this analysis. The Beer–Lambert law is linear up to 200 µM for TDN and 5–6 µM for TDP. Current analytical abilities for DON/DOP measurements are not ready yet to set the level of dissolved organic carbon analysis. The advance in the analytical performance for DON and DOP measurements depends upon the possibility to improve the analytical performance for dissolved inorganic N and P measurements involved in DON and DOP estimations. For the DOP analysis, an international standard method becomes necessary to develop and evaluate collaboratively. The chemical oceanographers’ community should reconsider requirements needed for the coverage of analytical performance for DON and DOP measurements to make this data more shareable and transparent. The lack of these data protracts marine analysts from attaining further methods improvement and development.  相似文献   

20.
The recombination radiation from organic solids, defined as the light emission following the fusion of oppositely charged carriers into an electrically neutral state, is discussed as a phenomenon underlying the function of organic light-emitting diodes (LEDs). Its intensity and spectral range depend on the population and nature of the emissive states, which differ, in general, from those created using light. These differences are pointed out and shown to be a result of the reverse pathways of the mutual transformation of localized molecular excitons and coulombically-correlated charge-pair excited states formed either by photoexcitation or electron-hole recombination. Spectral features of the radiation produced by the recombination of statistically independent charge carriers are discussed in terms of two molecules-based excited states like excimers or electromers in single-component materials and exciplexes or electroplexes in multicomponent materials. Consequences for optical and electrical characteristics of organic LEDs are discussed and illustrated by examples. Progress in the fundamental and applied research may be expected based on properties of recombination-produced electronic excited states.  相似文献   

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