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Dr. Ji Yang Dr. Jiawang Liu Dr. Yao Ge Weiheng Huang Dr. Helfried Neumann Dr. Ralf Jackstell Prof. Dr. Matthias Beller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20574-20578
A general and direct synthesis of dicarboxylic acids including industrially important adipic acid by palladium-catalyzed dicarbonylation of allylic alcohol is reported. Specifically, the combination of PdCl2 and a bisphosphine ligand (HeMaRaphos) promotes two different carbonylation reactions with high activity and excellent selectivity. 相似文献
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综述了钯催化的酸酐碳—氧键的活化和反应 ,及由羧酸直接制备相应的醛、酮且不需要卤原子和碱参与的方法 相似文献
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Haoquan Li Dr. Helfried Neumann Prof. Dr. Matthias Beller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):10050-10056
A benign and efficient palladium‐catalyzed aminocarbonylation reaction of allylic alcohols is presented. The generality of this novel process is demonstrated by the synthesis of β,γ‐unsaturated amides including aliphatic, cinnamyl, and terpene derivatives. The choice of ligand is crucial for optimal carbonylation processes: Whereas in most cases the combination of PdCl2 with Xantphos ( L6 ) gave best results, sterically hindered substrates performed better in the presence of simple triphenylphosphine ( L10 ), and primary anilines gave the best results using cataCXium® PCy ( L8 ). The reactivity of the respective catalyst system is significantly enhanced by addition of small amounts of water. Mechanistic studies and control experiments revealed a tandem allylic alcohol amination/C?N bond carbonylation reaction sequence. 相似文献
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Palladium‐Catalyzed Allylic Alkylation of Simple Ketones with Allylic Alcohols and Its Mechanistic Study 下载免费PDF全文
Xiaohong Huo Dr. Guoqiang Yang Prof. Delong Liu Prof. Yangang Liu Prof. Ilya D. Gridnev Prof. Wanbin Zhang 《Angewandte Chemie (International ed. in English)》2014,53(26):6776-6780
Allylic alcohols were directly used in Pd‐catalyzed allylic alkylations of simple ketones under mild reaction conditions. The reaction proceeded smoothly at 20 °C by the concerted action of a Pd catalyst, a pyrrolidine co‐catalyst, and a hydrogen‐bonding solvent, and does not require any additional reagents. A computational study suggested that methanol plays a crucial role in the formation of the π‐allylpalladium complex by lowering the activation barrier. 相似文献
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Thepalladium-catalyzedarylation0fallylicalc0h0lswitharylhalideshaspr0videdaconvenientmethodforthesynthesisof3-arylaldehydesandket0nesl'2.Benhaddouetal.3havestudiedthekineticsofthisarylationreaction.H0wever,homogene0uspalladiumcatalystssuchasPd(0Ac)2andPdCl2areusuallyused,anditisdifficulttorecuverthemfromthereactionmixture.ThemethodofinunobilizingcomPlexeshasmadehomogeneouscatalystsgenerallymoreattractivefromtheoreticalandindustrialpointsofview.Polymer-supportedpalladiumcatalystshavebeensucce… 相似文献
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Tim Meyer Dr. Jabor Rabeah Prof. Dr. Angelika Brückner Prof. Dr. Xiao-Feng Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(18):5642-5647
The palladium-catalyzed oxidative carbonylation of amines toward the synthesis of oxalamides has been established around 30 years ago and it usually needs the presence of (over)stoichiometric amounts of oxidant. In this work, the first transformation of this type in which the oxidant was replaced by visible light is described. The new approach uses a simple robust Pd complex, which can even be partially recycled. A mechanistic reason is provided and supported by control experiments and EPR studies, showing that PdI was formed and Pd0 was the active species. Both nitrogen- and the intermediate acyl radical can be detected. Moreover, the formation of hydrogen was confirmed by gas GC. 相似文献
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Liang Yan Jing‐Kun Xu Chao‐Fan Huang Zeng‐Yang He Ya‐Nan Xu Prof. Dr. Shi‐Kai Tian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(37):13041-13045
A new strategy has been established for the kinetic resolution of racemic allylic alcohols through a palladium/sulfonyl‐hydrazide‐catalyzed asymmetric OH‐substitution under mild conditions. In the presence of 1 mol % [Pd(allyl)Cl]2, 4 mol % (S)‐SegPhos, and 10 mol % 2,5‐dichlorobenzenesulfonyl hydrazide, a range of racemic allylic alcohols were smoothly resolved with selectivity factors of more than 400 through an asymmetric allylic alkylation of monosubstituted hydrazines under air at room temperature. Importantly, this kinetic resolution process provided various allylic alcohols and allylic hydrazine derivatives with high enantiopurity. 相似文献
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Wen Xia Liangzhen Hu Chenglong Ma Jiaqi Cao Xiaohui Zhang Prof. Dr. Yan Xiong 《European journal of organic chemistry》2023,26(16):e202300148
A rapid and efficient acid-promoted strategy to access allylic thiocyanates using allylic alcohols as substrates and easily-available NH4SCN as the thiocyanate source is presented under metal- and oxidant-free conditions. Through screening of various kinds of acids, organic and strong trifluoroacetic acid (TFA) was found most effective. Testing of substrates showed that the strategy has remarkable functional group tolerance. A possible mechanism is provided, and the gram-scale experiment demonstrate that this novel protocol has potential industrial application value. 相似文献
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Carbonylation of olefins, alcohols and halides using homogeneous as well as heterogeneous catalysts has been discussed. Highlights
of contributions on the activity, selectivity and stability of catalysts for carbonylation reactions are discussed. Kinetics
and mechanism including characterization of the intermediate catalytic species has also been reviewed. The performance of
anchored Pd complexes on mesoporous supports (MCM-41 and MCM-48), water soluble Pd complexes and supported Pd catalysts in
carbonylation of aryl alcohols and olefins has been discussed in the context of catalyst-product separation. Some aspects
of kinetic modelling and reaction engineering of these multiphase catalytic reactions have also been reviewed. 相似文献
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ZuminQiu YunbingHe DianmoZheng FufangLiu 《天然气化学杂志》2005,14(1):40-46
The influences of some factors on the yield of phenylacetic acid in the carbonylation of benzyl chloride were studied in this paper. These factors included the variety and content of catalyst, and that of solvent, way of material feeding, reaction temperature, sodium hydrate concentration, triphenylphosphine content, presence of surfactant, the ratio of organic phase volume to aqueous phase volume etc. The optimum reaction conditions were found to be: with a one-time pour of 0.15g Pd(PPh3)2Cl2, 0.24g PPh3, 75ml NaOH of 3.5mol/L, 20ml benzyl chloride and 55ml n-butyl alcohol, and the reaction was carried out at 50℃ for about 3 hours. The as-obtained yield of phenylacetic acid was as high as 97.6%. In addition, the influences of the presence of phenylacetic acid and air in the reaction system were also studied. The results showed that the presence of air in the system and the entrainment of phenylacetic acid in the circulating organic phase had great influence on the reaction rate, the stability and performance of catalyst and the yield of phenylacetic acid. 相似文献
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Dr. Tsuyoshi Mita Yuki Higuchi Prof. Dr. Yoshihiro Sato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16391-16394
Various allylic alcohols were carboxylated in the presence of a catalytic amount of PdCl2 and PPh3 using ZnEt2 as a stoichiometric transmetalation agent under a CO2 atmosphere (1 atm). This carboxylation proceeded in a highly regioselective manner to afford branched carboxylic acids predominantly. The β,γ‐unsaturated carboxylic acid thus obtained was successfully converted into an optically active γ‐butyrolactone, a known intermediate of (R)‐baclofen. 相似文献
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Xiaoyun Wu Dr. Wei Ma Prof. Dr. Weijun Tang Prof. Dr. Dong Xue Prof. Dr. Jianliang Xiao Prof. Dr. Chao Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(60):e202201829
Allylic amines are useful building blocks in organic synthesis, so the development of green and efficient methods for the preparation of allylic amines are of great importance. An Fe-catalyzed amidation of allylic alcohols with chiral tert-butylsulfinamide has been developed. With water as the only by-product, a range of synthetically useful chiral sulfinamide olefin derivatives (30 examples) were obtained under mild reaction conditions. The reaction can be performed on a gram-scale, and the products could serve as chiral ligands for asymmetric catalysis. Mechanistic studies suggest that the reaction proceeds by an Fe-catalyzed borrowing hydrogen process, which is different from most of the reported allylic amination reactions. 相似文献
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Wei Ming XU You Chu ZHANG Xian HUANG* Department of Chemistry Zhejiang University 《中国化学快报》2003,14(8)
Combinatorial chemistry and solid phase synthesis have recently emerged as powerful tools for the drug discovery process1. It might be argued that selenoxide syn- elimination provided the principal impetus for the development of organoselenium chemistry. [2, 3] Sigmatropic rearrangement2 of allylic selenium compounds is the most fundamental reaction in the field of synthetic organoselenium chemistry as well as selenoxide syn-elimination. However, organic selenides are highly malodorous and … 相似文献
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Cooperative Catalysis by Palladium and a Chiral Phosphoric Acid: Enantioselective Amination of Racemic Allylic Alcohols 下载免费PDF全文
Dr. Debasis Banerjee Dr. Kathrin Junge Prof. Dr. Matthias Beller 《Angewandte Chemie (International ed. in English)》2014,53(48):13049-13053
Cooperative catalysis by [Pd(dba)2] and the chiral phosphoric acid BA1 in combination with the phosphoramidite ligand L8 enabled the efficient enantioselective amination of racemic allylic alcohols with a variety of functionalized amines. This catalytic protocol is highly regio‐ and stereoselective (up to e.r. 96:4) and furnishes valuable chiral amines in almost quantitative yield. 相似文献