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1.
C‐2 Selective Arylation of Indoles with Heterogeneous Nanopalladium and Diaryliodonium Salts 下载免费PDF全文
Joel Malmgren Anuja Nagendiran Dr. Cheuk‐Wai Tai Prof. Jan‐E. Bäckvall Prof. Berit Olofsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13531-13535
A simple and efficient method to prepare synthetically useful 2‐arylindoles is presented, using a heterogeneous Pd catalyst and diaryliodonium salts in water under mild conditions. A remarkably low leaching of metal catalyst was observed under the applied conditions. The developed protocol is highly C‐2 selective and tolerates structural variations both in the indole and in the diaryliodonium salt. Arylations of both N?H indoles and N‐protected indoles with ortho‐substituted, electron‐rich, electron‐deficient, or halogenated diaryliodonium salts were achieved to give the desired products in high to excellent isolated yields within 6 to 15 h at room temperature or 40 °C. 相似文献
2.
Zsombor Gonda Dr. Zoltán Novák 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(47):16801-16806
A new synthetic method was developed for the N‐arylation of pyrazoles using diaryliodonium salts. The transformation does not require any transition‐metal catalyst and provides the desired N‐arylpyrazoles rapidly under mild reaction condition in the presence of aqueous ammonia solution as a mild base without the use of inert atmosphere. The chemoselectivity of unsymmetric diaryliodonium salts was also explored with large number of examples. 相似文献
3.
Xu Geng Song Mao Liangshun Chen Jianjun Yu Jianwei Han Jianli Hua Limin Wang 《Tetrahedron letters》2014
An efficient copper-catalyzed N-arylation of N-arylsulfonamides with diaryliodonium salts is reported. The reaction employs diaryliodonium salts and N-arylsulfonamides in water at room temperature, giving the products in moderate to excellent yields. 相似文献
4.
James V. Crivello Julia L. Lee 《Journal of polymer science. Part A, Polymer chemistry》2010,48(20):4484-4495
In this article, a new route for the synthesis of N‐aryl heteroaromatic onium salts by the direct copper catalyzed arylation of pyridine, substituted pyridines, isoquinoline, and acridine with diaryliodonium salts is described. It was demonstrated that these N‐aryl heteroaromatic onium salts undergo facile platinum or rhodium‐catalyzed reduction by silanes bearing Si? H groups. The reduction of N‐aryl heteroaromatic onium salts generates Brønsted acids. When this redox reaction was carried out in situ in the presence of an appropriate monomer, cationic polymerization was observed. Using this approach, the cationic polymerizations of epoxides, oxetanes, 1,3,5‐trioxane, styrene, and vinyl ethers were carried out. The use of optical pyrometry to monitor the redox initiated cationic polymerizations of some representative multifunctional monomers is described. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
5.
New glycosyl donors have been developed that contained several para‐substituted O‐aryl protecting groups and their stereoselectivity for the glycosylation reaction was evaluated. A highly β‐selective glycosylation reaction was achieved by using thioglycosides that were protected by 4‐nitrophenyl (NP) groups, which were introduced by using the corresponding diaryliodonium triflate. Analysis of the stereoselectivities of several glycosyl donors indicated that the β‐glycosides were obtained through an SN2‐type displacement from the corresponding α‐glycosyl triflate. The NP group could be removed by reduction of the nitro group and acylation, followed by oxidation with ceric ammonium nitrate (CAN). 相似文献
6.
Erika Linde Prof. Berit Olofsson 《Angewandte Chemie (International ed. in English)》2023,62(48):e202310921
The diarylation and skeletal diversification of unstrained cyclic amines was exploited to expand and modify the favorable properties of this important substrate class with pivotal roles in drug discovery. Cyclic amines were employed in the synthesis of a novel class of amino-substituted diaryliodonium salts, which were converted to highly functionalized diarylamines through an atom-efficient one-pot N-arylation/ring opening reaction with external nucleophiles. The reaction proceeds through in situ formation of a diarylammonium intermediate that undergoes a nucleophilic ring opening by cleavage of the strong C−N bond. A wide variety of diarylamines was obtained through introduction of two different aryl groups of varied electronics, and the retained iodo-substituent enables downfield diversifications of the products. More than 20 nucleophiles, including amines, phenols, carboxylic acids, thiols and halides, were alkylated with high functional group tolerance, and the strategy proved efficient also in in late-stage functionalization of natural products and pharmaceuticals. 相似文献
7.
N‐Arylation of uracil and its derivatives 2 with diaryliodonium salts 1 was investigated in order to explore a new synthetic methodology associated with N‐aryluracil derivatives. In the presence of K2CO3, the copper‐catalyzed arylation gave N1,N3‐diarylation products with high selectivity and in good yields (Table 2). However, the use of NaOAc as the base in the copper‐catalyzed arylation of 6‐methyluracil ( 2a ) resulted in N3‐arylation products with high selectivity, and, in the copper‐catalyzed arylation of uracil ( 2b ) or 5‐methyluracil (=thymine; 2c ), N1‐arylation products were the major products (Table 3). 相似文献
8.
Masami Kuriyama Natsumi Hanazawa Yusuke Abe Kotone Katagiri Shimpei Ono Kosuke Yamamoto Osamu Onomura 《Chemical science》2020,11(31):8295
Metal-free N- and O-arylation reactions of pyridin-2-ones as ambident nucleophiles have been achieved with diaryliodonium salts on the basis of base-dependent chemoselectivity. In the presence of N,N-diethylaniline in fluorobenzene, pyridin-2-ones were very selectively converted to N-arylated products in high yields. On the other hand, the O-arylation reactions smoothly proceeded with the use of quinoline in chlorobenzene, leading to high yields and selectivities. In these methods, a variety of pyridin-2-ones in addition to pyridin-4-one and a set of diaryliodonium salts were accepted as suitable reaction partners.The metal-free N- and O-arylation reactions of pyridin-2-ones with diaryliodonium salts were achieved on the basis of base-dependent chemoselectivity. 相似文献
9.
With a strategy by using diaryliodonium salts as the precursors of benzynes, direct N-arylation of tertiary amines with diaryliodonium salts was reported. Thus, the desired aromatic tertiary amines with a wide range of substituents were synthesized in moderate to excellent yields of 55–91%. 相似文献
10.
Yu Wang Wanying Pan Yuxuan Zhang Limin Wang Jianwei Han 《Angewandte Chemie (International ed. in English)》2023,62(28):e202304897
The Truce-Smiles rearrangement is an intramolecular SNAr reaction, enabling the formation of a new arene carbon-carbon bond with sufficiently strong carbon-centered nucleophile. Reported here are ortho-tosylmethylene functionalized diaryliodonium salts, which can undergo an unprecedented Truce-Smiles rearrangement in ionic liquids, resulting in sulfonyl-substituted ortho-iodo diarylmethanes as a powerful class of building blocks in chemical synthesis. The protocol features aryliodo moiety as a hyper nucleofuge, facilitating the formation of Meisenheimer complex within the migratory system. 相似文献
11.
Nazli Jalalian Dr. Tue B. Petersen Prof. Berit Olofsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(44):14140-14149
Phenols and carboxylic acids are efficiently arylated with diaryliodonium salts. The reaction conditions are mild, metal free, and avoid the use of halogenated solvents, additives, and excess reagents. The products are obtained in good‐to‐excellent yields after short reaction times. Steric hindrance is very well tolerated, both in the nucleophile and diaryliodonium salt. The scope includes ortho‐ and halo‐substituted products, which are difficult to obtain by metal‐catalyzed protocols. Many functional groups are tolerated, including carbonyl groups, heteroatoms, and alkenes. Unsymmetric salts can be chemoselectively utilized to obtain products with hitherto unreported levels of steric congestion. The arylation has been extended to sulfonic acids, which can be converted to sulfonate esters by two different approaches. With recent advances in efficient synthetic procedures for diaryliodonium salts the reagents are now inexpensive and readily available. The iodoarene byproduct formed from the iodonium reagent can be recovered quantitatively and used to regenerate the diaryliodonium salt, which improves the atom economy. 相似文献
12.
Yujing Hua James V. Crivello 《Journal of polymer science. Part A, Polymer chemistry》2000,38(19):3697-3709
A kinetic study was conducted of the independent photoinitiated cationic polymerization of a number of epoxide monomers and mixtures of these monomers with N‐vinylcarbazole. The results show that these two different classes of monomers undergo complex synergistic interactions with one another during polymerization. It was demonstrated that N‐vinylcarbazole as well as other carbazoles are efficient photosensitizers for the photolysis of both diaryliodonium and triarylsulfonium salt photoinitiators. In the presence of large amounts of N‐vinylcarbazole, the rates of the cationic ring‐opening photopolymerization of epoxides are markedly accelerated. This effect has been ascribed to a photoinitiated free‐radical chain reaction that results in the oxidation of monomeric and polymeric N‐vinylcarbazole radicals by the onium salt photoinitiators to generate cations. These cations can initiate the ring‐opening polymerization of the epoxides, leading to the production of copolymers. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3697–3709, 2000 相似文献
13.
Ahmed Chaambi Gülbin Kurtay Raoudha Abderrahim Frdric Robert Yannick Landais 《Helvetica chimica acta》2019,102(8)
The free‐radical alkenylation of a range of alkyl iodides with a vinyldisulfones has been carried out, leading to the desired vinylsulfones in moderate to good yields under mild conditions. The process is initiated by an aryl radical which abstracts the iodine atom from the alkyl iodide to form a C‐centered radical intermediate, the addition of which onto the vinyldisulfone providing the final vinylsulfone. The aryl radical is generated in situ through a single‐electron transfer from an electron donor‐acceptor complex (EDA) formed between a diaryliodonium salt (Ph2I+ PF6?) and triethylamine. 相似文献
14.
Junichi Shikuma Atsunori Mori Prof. Dr. Kentaro Masui Ryuichi Matsuura Akitoshi Sekiguchi Haruka Ikegami Masuki Kawamoto Dr. Tomiki Ikeda Prof. Dr. 《化学:亚洲杂志》2007,2(2):301-305
The synthesis of donor–acceptor‐type 2,5‐diarylthiazoles that bear electron‐donating N,N‐dialkylamine and electron‐withdrawing cyano groups at the 2‐ and 5‐position, respectively, were carried out with transition‐metal‐catalyzed C? H arylation reactions developed by us. The compounds were synthesized by the C? H arylation of unsubstituted thiazole at the 2‐position with a palladium/copper catalyst in the presence of tetrabutylammonium fluoride (TBAF) as an activator. Further C? H arylation of the 2‐arylated thiazole at the 5‐position was carried out by the palladium‐catalyzed reaction in the presence of silver(I) fluoride to afford the donor–acceptor‐type 2,5‐diarylthiazoles with N,N‐dialkylamine groups of different chain lengths. The UV/Vis absorption, photoluminescence, and electrochemical behavior were similar regardless of chain length, whereas liquid‐crystalline behavior and thermal characteristics were found to be dependent on the alkyl‐chain length. The compounds with N,N‐diethylamine or N‐butyl‐N‐methyl groups showed a stable liquid‐crystalline phase over a wide temperature range as well as higher stability to thermal decomposition. 相似文献
15.
Cheng Pan Prof. Dr. Limin Wang Prof. Dr. Jianwei Han 《Chemical record (New York, N.Y.)》2023,23(10):e202300138
Our research interest focusing on synthetic methodology with diaryliodonium salts, is summarized in this account. Besides employing a dual activation strategy of C−I and ortho C−H bonds, we have introduced vicinal functional groups at ortho-positions of diaryliodonium salts, in which their unique reactivities have been explored in various processes, including arylation, diarylation, cascade annulation, benzocyclization, arylocyclization, and intramolecular aryl migration. The variety of mechanisms of these reactions that involves either transition metals, especially palladium in organometallic catalysis, or transition-metal free conditions, were discussed in the context. 相似文献
16.
Erika Linde Niels Knippenberg Prof. Berit Olofsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(69):e202202453
Two regioselective, high-yielding one-pot routes to oxygen-bridged cyclic diaryliodonium salts and ortho-aryloxy-substituted acyclic diaryliodonium salts are presented. Starting from easily available ortho-iodo diaryl ethers, complete selectivity in formation of either the cyclic or acyclic product could be achieved by varying the reaction conditions. The complimentary reactivities of these novel ortho-oxygenated iodonium salts were demonstrated through a series of chemoselective arylations under metal-catalyzed and metal-free conditions, to deliver a range of novel, ortho-functionalized diaryl ether derivatives. 相似文献
17.
Tian Lan Xiaofen Chen Zenglu Liu Zhenmin Mao 《Journal of heterocyclic chemistry》2013,50(5):1094-1098
A facile and effective synthesis of N‐vinylpyrroles had been explored. The synthetic approach was practicable for preparation of N‐vinylpyrroles for the mild reaction conditions and readily available materials, compared with previously inaccessible N‐vinylpyrroles with electron‐withdrawing groups, especially these pyrroles bearing alkaline sensitive substitution groups. 相似文献
18.
Copper-Catalyzed Synthesis of Axially Chiral Biaryls with Diaryliodonium Salts as Arylation Reagents
NOBIN and BINAM derivatives harboring biaryl frameworks are recognized as a class of important atropisomers with versatile applications. Here, we present an efficient synthetic route to access such compounds through copper-catalyzed domino arylation of N-arylhydroxylamines or N-arylhydrazines with diaryliodonium salts and [3,3]-sigmatropic rearrangement. This reaction features mild conditions, good substrate compatibility, and excellent efficiency. The practicality of this protocol was further extended by the synthesis of biaryl amino alcohols. 相似文献
19.
Xin Liu Dan Mao ShengYing Wu JianJun Yu Gang Hong Qiao Zhao LiMin Wang 《中国科学:化学(英文版)》2014,57(8):1132-1136
<正>1 The study of reaction conditions Table S1 The optimization of the rate of copper slats and ligand a) Entry Anion Cu/ligand Yield b)(%) 1 2 3 OTf OTf OTf 10%:20% 10%:10% 5%:10% 91 65 45 a) Reaction conditions: 1a(0.60 mmol), 2a(0.20 mmol), Cu(OTf)2(x mol%), K2CO3(2.5 equiv.), 1,10-phenanthroline(y mol%), DMSO(2 mL), 150 °C, 24 h; b) isolated yields. Table S2 The optimization of the substrates' rate a) Entry 1a/2a(mmol) Yield b)(%) 1 2 3 4 5 6 0.2:0.2 0.2:0.24 0.2:0.4 0.6:0.2 0.4:0.2 1.0:0.2 54 60 58 91 73 83 a) Reaction conditions: 1a(x mmol), 2a(y mmol), Cu(OTf)2(10 mol%), K2CO3(2.5 equiv.), 1,10-phenanthroline(20 mol%), DMSO(2 mL), 150 °C, 24 h; b) isolated yields. 相似文献
20.
Kun‐Heng Chiang Shi‐Han Lu Wan‐Ping Yen Naoto Uramaru Wei‐Siou Tseng Te‐Wei Chang Fung Fuh Wong 《Heteroatom Chemistry》2016,27(4):235-242
A convenient synthetic method for N‐arylformamide derivatives was successfully developed by reacting α‐iodo‐N‐arylacetamides with formamide. This method was applicable to α‐iodo‐N‐arylacetamide substrates bearing electron‐donating or electron‐withdrawing groups, N‐(benzo[d][1,3]dioxol‐5‐yl)‐2‐iodoacetamide, 2‐iodo‐N‐(pyridin‐2‐yl)acetamide, and 2‐iodo‐N‐(naphthalen‐4‐yl)acetamide to give the corresponding N‐arylformamides in moderate to excellent yields (65–94%). A plausible mechanism was proposed to account for the new transformation. 相似文献