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1.
Jeffrey Buter Dorus Heijnen Carlos Vila Valentín Hornillos Edwin Otten Massimo Giannerini Adriaan J. Minnaard Ben L. Feringa 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(11):3684-3688
A palladium‐catalyzed direct synthesis of symmetric biaryl compounds from aryl halides in the presence of tBuLi is described. In situ lithium–halogen exchange generates the corresponding aryl lithium reagent, which undergoes a homocoupling reaction with a second molecule of the aryl halide in the presence of the palladium catalyst (1 mol %). The reaction takes place at room temperature, is fast (1 h), and affords the corresponding biaryl compounds in good to excellent yields. The application of the method is demonstrated in an efficient asymmetric total synthesis of mastigophorene A. The chiral biaryl axis is constructed with an atropselectivity of 9:1 owing to catalyst‐induced remote point‐to‐axial chirality transfer. 相似文献
2.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(17):4855-4859
The palladium‐catalyzed asymmetric synthesis of enone‐based atropisomers from 2‐iodo‐3‐methylcyclohex‐2‐enones and aryl boronic acid is reported. BoPhoz‐type phosphine–aminophosphine ligands showed superior enantioselectivity over other ligands. These cyclohexenone‐based atropisomers are useful compounds for further elaboration. The divergent synthesis of biaryl atropisomers with different ortho substituents was demonstrated. 相似文献
3.
cis,cis,cis‐1,2,3,4‐Tetrakis(diphenylphosphinomethyl)cyclopentane–[PdCl(C3H5)]2 efficiently catalyses the Heck reaction of alk‐1‐en‐3‐ol with a variety of aryl halides. In the presence of hex‐1‐en‐3‐ol or oct‐1‐en‐3‐ol, the β‐arylated carbonyl compounds were selectively obtained. Turnover numbers up to 84 000 can be obtained for this reaction. Linalool and 2‐methylbut‐3‐en‐2‐ol led regio‐ and stereoselectively to the corresponding (E)‐1‐arylalk‐1‐en‐3‐ol derivatives. A minor electronic effect of the substituents of the aryl bromide was observed. Quite similar reaction rates were generally observed in the presence of activated aryl bromides such as bromoacetophenone and deactivated aryl bromides such as bromoanisole, indicating that, with these alkenols and this catalyst, the oxidative addition of aryl bromides to palladium is not the rate‐limiting step. It should be noted that this reaction also proceeds with sterically very congested aryl bromides such as 9‐bromoanthracene or 2,4,6‐triisopropylbromobenzene or with a vinyl bromide. On the other hand, low yields were obtained with aryl chlorides. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
4.
Tomohiro Sugahara Prof. Dr. Kei Murakami Prof. Dr. Hideki Yorimitsu Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (International ed. in English)》2014,53(35):9329-9333
A combination of a palladium–NHC catalyst and potassium hexamethyldisilazide enables the amination of aryl sulfides with anilines to afford a wide variety of diarylamines. The reaction conditions are versatile enough for the reaction of even bulky ortho‐substituted aryl sulfides. This amination can be applied to the modular synthesis of N‐aryl carbazoles from the corresponding ortho‐bromothioanisoles. As aryl sulfoxides undergo extended Pummerer reactions to afford ortho‐substituted aryl sulfides, the Pummerer products are thus useful substrates for the amination to culminate in efficient syntheses of a 2‐anilinobenzothiophene and an indole as proof‐of‐principle of the utility of the extended Pummerer reaction/amination cascade. 相似文献
5.
Nanostructured Pyrophosphate Na2PdP2O7‐Catalyzed Suzuki‐Miyaura Cross‐Coupling Under Microwave Irradiation 下载免费PDF全文
Karim Dânoun Younes Essamlali Othmane Amadine Rida Tabit Aziz Fihri Christophe Len Mohamed Zahouily 《应用有机金属化学》2018,32(4)
Nanostructured palladium pyrophosphate (Na2PdP2O7) catalyst was synthesized and well characterized by using different techniques (TGA, XRD, SEM, TEM....). This nanocatalyst exhibited excellent catalytic activity in the synthesis of biaryl compounds via Suzuki‐Miyaura cross‐coupling to produce their corresponding products in good to excellent yields under mild conditions. The catalyst is recyclable and was recycled for four runs for the reaction of 4‐bromoacetophenone with phenylboronic acid without appreciable loss of its catalytic activity. 相似文献
6.
Application of the Suzuki cross‐coupling reaction for efficient synthesis of diverse substituted biaryl‐chromen‐4‐ones using an optimized palladium(0) catalyst system is reported. The coupling of arylboronic acids with the resin‐bound bromoflavanones which were prepared by organoselenium‐induced regioselective intramolecular cyclization of bromo‐2‐hydroxylchalcones proceeded smoothly. Biaryl‐chromen‐4‐ones were synthesized by subsequent selenoxide syn‐elimination in good total yields. 相似文献
7.
In this study, magnetic nitrogen‐doped carbon (MNC) was fabricated through facile carbonization and activation of natural silk cocoons containing nitrogen and then combined with Fe3O4 nanoparticles to create a good support material for palladium. Palladium immobilization on the support resulted in the formation of magnetic nitrogen‐doped carbon‐Pd (MNC‐Pd). The prepared heterogeneous catalyst was well characterized using FT‐IR, TGA, EDX, FE‐SEM, XRD, VSM, and ICP‐OES techniques. Thereafter, the synthesis of biaryl compounds was conducted to investigate the catalyst performance via the reaction of aryl halides and phenylboronic acid. Further, the catalyst could be used and recycled for six consecutive runs without any significant loss in its activity. 相似文献
8.
《中国化学》2018,36(2):153-156
A series of structurally novel P‐chiral biaryl bisphosphorus ligands L1‐L5 (BABIBOPs) are developed, providing high efficiency for the first time in palladium‐catalyzed asymmetric hydrogenation of β‐aryl and β‐alkyl substituted β‐keto esters. With the Pd‐ L3 (iPr‐BABIBOP) catalyst, a series of chiral β‐hydroxyl carboxylic esters are formed in excellent enantioselectivities (up to>99% ee) and yields at catalyst loading as low as 0.01 mol%. 相似文献
9.
A palladium catalyst was synthesized using N‐benzyl DABCO chloride and palladium chloride. The structure of this catalyst was characterized and then the catalyst was used in Suzuki cross‐ coupling reaction of different aryl halides with arylboronic acids. All substrates afforded the corresponding products in good to high yields in the presence of low amounts of the catalyst. Under the heating conditions employed, cheaper and more available aryl chlorides gave relatively high yields in the Suzuki reaction. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
Yaoyu Liang Jieying Ji Xiaoyan Zhang Quanbin Jiang Jie Luo Xiaodan Zhao 《Angewandte Chemie (International ed. in English)》2020,59(12):4959-4964
The enantioselective construction of axially chiral compounds by electrophilic carbothiolation of alkynes is disclosed for the first time. This enantioselective transformation is enabled by the use of a Ts‐protected bifunctional sulfide catalyst and Ms‐protected ortho‐alkynylaryl amines (Ts=tosyl; Ms=mesyl). Both electrophilic arylthiolating and electrophilic trifluoromethylthiolating reagents are suitable for this reaction. The obtained products of axially chiral vinyl–aryl amino sulfides can be easily converted into biaryl amino sulfides, biaryl amino sulfoxides, biaryl amines, vinyl–aryl amines, and other valuable difunctionalized compounds. 相似文献
11.
Treatment of aryl iodides with indium metal in the presence of lithium chloride leads to the formation of an organoindium reagent capable of participating in cross-coupling reactions under transition-metal catalysis. Combination with aryl halides in the presence of 5 mol % Cl2Pd(dppf) furnishes biaryl compounds in good yields; similarly, reaction with acyl halides or allylic acetates/carbonates in the presence of 5-10 mol % palladium catalyst leads to arylketones and allylic substitution products, respectively, in moderate yields. The reactions are tolerant of the presence of protic solvents, and approximately 85% of the indium metal employed can be recovered by reduction of the residual indium salts with zinc(0). 相似文献
12.
1‐Bromoallyl bromides are carbonylatively cyclized with anilines under carbon monoxide pressure in DMF in the presence of a catalytic amount of a palladium catalyst along with a base to give the corresponding 1‐aryl‐1H‐pyrrol‐2(5H)‐ones in moderate to good yield. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
13.
Palladium‐Catalysed Direct Cross‐Coupling of Organolithium Reagents with Aryl and Vinyl Triflates 下载免费PDF全文
Dr. Carlos Vila Dr. Valentín Hornillos Massimo Giannerini Dr. Martín Fañanás‐Mastral Prof. Dr. Ben L. Feringa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13078-13083
A palladium‐catalysed cross‐coupling of organolithium reagents with aryl and vinyl triflates is presented. The reaction proceeds at 50 or 70 °C with short reaction times, and the corresponding products are obtained with moderate to high yields, with a variety of alkyl and (hetero)aryl lithium reagents. 相似文献
14.
本文报道了有机-无机杂化材料固载的钯催化的无铜Sonogashira偶联反应。在3-[N,N-双(二苯基膦)氨基)]丙基功能化的硅胶固载的钯催化下,末端炔烃和碘代芳烃、溴代芳烃的偶联反应生成高产率相应的偶联产物。反应条件包括使用乙二醇为溶剂,三乙胺为碱。而且硅胶负载的膦钯催化剂和溶剂乙二醇经简单处理,可循环使用6次不降低活性。 相似文献
15.
In this study, synthesis, characterization and catalytic performance of a novel supramolecular photocatalytic system including palladium (II) encapsulated within amine‐terminated poly (triazine‐triamine) dendrimer modified TiO2 nanoparticles (Pd (II) [PTATAD] @ TiO2) is presented. The obtained nanodendritic catalyst was characterized by FT‐IR, ICP‐AES, XPS, EDS, TEM, TGA and UV‐DRS. The as‐prepared nanodendritic catalyst was shown to be highly active, selective, and recyclable for the Suzuki–Miyaura and Sonogashira cross‐coupling of a wide range of aryl halides including electron‐rich and electron‐poor and even aryl chlorides, affording the corresponding biaryl compounds in good to excellent yields under visible light irradiation. This study shows that visible light irradiation can drive the cross‐coupling reactions on the Pd (II) [PTATAD] @ TiO2 under mild reaction conditions (27–30 °C) and no additional additives such as cocatalysts or phosphine ligands. So, we propose that the improved photoactivity predominantly benefits from the synergistic effects of Pd (II) amine‐terminated poly (triazine‐triamine) dendrimer on TiO2 nanoparticles that cause efficient separation and photogenerated electron–hole pairs and photoredox capability of nanocatalyst which all of these advantages due to the tuning of band gap of catalyst in the visible light region. 相似文献
16.
17.
The reaction of piperdin-2-ones with a 2-bromobenzyl substituent in the 5-position in the presence of a palladium catalyst leads to biaryl compounds. Their formation can be explained via initial C-H insertion of the aryl palladium species into the allylic C-H bond of the piperidinone. This eventually leads to a metallacycle containing Pd(II) that inserts another aryl bromide, promoting the formation of the biaryl bond. 相似文献
18.
Seema Yadav Ajeet Singh Isha Mishra Sriparna Ray Shaikh M. Mobin Chandrakanta Dash 《应用有机金属化学》2019,33(7)
Well‐defined and air‐stable PEPPSI (Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation) themed palladium bis‐N‐heterocyclic carbene complexes have been developed for the domino Sonogashira coupling/cyclization reaction of 2‐iodophenol with a variety of terminal alkynes and C‐H bond arylation of benzothiazole with aryl iodides. The PEPPSI themed palladium complexes, 2a and 2b were synthesized in good yields from the reaction of corresponding imidazolium salts with PdCl2 and K2CO3 in pyridine. The new air‐stable palladium‐NHC complexes were characterized by NMR spectroscopy, X‐ray crystallography, elemental analysis, and mass spectroscopy studies. The PEPPSI themed palladium(II) bis‐N‐heterocyclic carbene complexes 2a and 2b exhibited excellent catalytic activities for domino Sonogashira coupling/cyclization reaction of 2‐iodophenol with terminal alkynes yielding benzofuran derivatives. In addition, the palladium complexes, 2a and 2b successfully catalyzed the direct C‐H bond arylation of benzothiazole with aryl iodides as coupling partners in presence of CuI as co‐catalyst. 相似文献
19.
SBA‐15‐functionalized melamine–pyridine group‐supported palladium(0) as an efficient heterogeneous and recyclable nanocatalyst for N‐arylation of indoles through Ullmann‐type coupling reactions 下载免费PDF全文
SBA‐15‐functionalized melamine–pyridine group‐supported palladium(0) was found to serve as a heterogeneous and recyclable nanocatalyst for N‐arylation of indoles with aryl iodides under a low catalyst loading (0.3 mol% of Pd) through Ullmann‐type C? N coupling reactions. A variety of aryl iodides could be aminated to provide the N‐arylated products in good to excellent yields without the need of an inert atmosphere. Also, this catalyst was found to be an efficient system for the N‐arylation of other nitrogen‐containing heterocycles with aryl iodides. The heterogeneous palladium catalyst could be recovered by simple filtration of the reaction solution and reused for six cycles without significant loss in its activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
20.
Can Liu Tao Miao Lei Zhang Prof. Pinhua Li Yicheng Zhang Prof. Lei Wang 《化学:亚洲杂志》2014,9(9):2584-2589
A novel and efficient palladium‐catalyzed C2 arylation of N‐substituted indoles with 1‐aryltriazenes for the synthesis of 2‐arylindoles was developed. In the presence of BF3 ? OEt2 and palladium(II) acetate (Pd(OAc)2), N‐substituted indoles reacted with 1‐aryltriazenes in N,N‐dimethylacetamide (DMAC) to afford the corresponding aryl–indole‐type products in good to excellent yields. 相似文献