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1.
Aromatic amines is not used commonly in allylic amination, presumably because of their less nucleophilic nature compared with the more extensively used benzylamine or relatively stable anionic nitrogen nucleophiles. An eco‐friendly method for C–O bond activation of allylic acetates using palladium associated with ligands in water leading to N‐allylation was described in this study. The palladium‐catalyzed allylic amination of allylic acetate with aminonaphthalenes gave 34–95% yields to the corresponding N‐allylic aminonaphthalenes. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
2.
Using N‐Tosylhydrazone as a Double Nucleophile in the Palladium‐Catalyzed Cross‐Coupling Reaction To Synthesize Allylic Sulfones
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Ping‐Xin Zhou Dr. Yu‐Ying Ye Dr. Lian‐Biao Zhao Dr. Jian‐Ye Hou Xing Kang Dao‐Qian Chen Qian Tang Jie‐Yu Zhang Qi‐Xing Huang Lan Zheng Jun‐Wei Ma Prof. Peng‐Fei Xu Prof. Yong‐Min Liang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(49):16093-16096
Without extra addition of sulfinate salt, allylic sulfones were synthesized by palladium‐catalyzed cross‐coupling of aryl iodide with N‐tosylhydrazone. In this transformation, not only the diazo compound but also the sulfinate salt, which were both generated in situ from base‐mediated decomposition of the N‐tosylhydrazone, was used as nucleophilic partner. 相似文献
3.
The direct activation of CO bonds in allylic alcohols by palladium complexes has been accelerated by carrying out the reactions in the presence of titanium reagents. The palladium-catalyzed amination of allylic alcohols using aminonaphthalenes gave N-allylic naphthylamines in good yields. The monoallylation products are formed in the main. 相似文献
4.
《中国化学》2018,36(10):929-933
A new palladium‐catalyzed selective aminomethylation of conjugated 1,3‐dienes with aminals via double C—N bond activation is described. This simple method provides an effective and rapid approach for the synthesis of linear α,β‐unsaturated allylic amines with perfect regioselectivity. Mechanistic studies disclosed that one palladium catalyst cleaved two distinct C—N bond to furnish a cascade double C—N bond activation, in which an allylic 1,3‐diamine and allylic 1,2‐diamine were initially formed as key intermediates through the palladium‐catalyzed C—N bond activation of aminal and the α,β‐unsaturated allylic amine was subsequently produced via palladium‐catalyzed C—N bond activation of the allylic diamines. 相似文献
5.
Rafet Kılınçarslan M. Emin Günay Rukiye Fırıncı Serpil Denizaltı Bekir Çetinkaya 《应用有机金属化学》2016,30(5):268-272
A new series of sterically hindered ligands containing (1R,2S,4R)‐(+)‐menthoxymethyl group attached to benzimidazole‐based N‐heterocyclic carbene (NHC), palladium–bis‐NHC complexes and (κ2‐C,N)‐palladacyclic NHC complexes have been synthesized and characterized using appropriate spectroscopic techniques. Catalytic performance of the palladium complexes has been investigated for allylic alkylation, Suzuki and Heck carbon–carbon coupling reactions. These complexes smoothly catalyse the carbon–carbon bond formation reactions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
6.
New chiral N,S-ligands with oxazoline and thiophenyl sub-stituents at benzene ring and benzylic postition have been pre-pared and applied in palladium-catalyzed asymmetric allylic alkylation reaction to provide the product with high yield and entantioselectivity (82%-93%)ee. 相似文献
7.
Regio‐ and Enantioselective Synthesis of N‐Allylindoles by Iridium‐Catalyzed Allylic Amination/Transition‐Metal‐Catalyzed Cyclization Reactions
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Ke‐Yin Ye Prof. Li‐Xin Dai Prof. Shu‐Li You 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(11):3040-3044
Regio‐ and enantioselective synthesis of N‐allylindoles was realized through an iridium‐catalyzed asymmetric allylic amination reaction with 2‐alkynylanilines and subsequent transition‐metal‐catalyzed cyclization reactions. The highly enantioenriched allylic amines prepared from Ir‐catalysis were treated with catalytic amount of NaAuCl4 ? 2 H2O or PdCl2 providing various substituted N‐allylindoles in excellent yields and enantioselectivities. 相似文献
8.
Phenyl‐modified natural rubber was prepared in latex stage by bromination of deproteinized natural rubber followed by Suzuki‐Miyaura cross‐coupling reaction. First, the bromination of natural rubber was carried out using N‐bromosuccinimide in latex stage. The bromine atom content increased as amount of N‐bromosuccinimide increased. Second, the allylic bromine atom was replaced with a phenyl group using phenyl boronic acid in the presence of a palladium catalyst, according to the Suzuki‐Miyaura cross‐coupling reaction in latex stage. The resulting products were characterized by nuclear magnetic resonance (NMR) spectroscopy. Signal at 7.13 ppm was assigned to the phenyl group of the product, while signals at 3.98, 4.14, and 4.44 ppm were assigned to the remaining allylic brominated cis‐1,4‐isoprene units. The estimated phenyl group content and the conversion of the Suzuki‐Miyaura cross‐coupling reaction were 1.32 and 23.7 mol%, respectively. Glass transition temperature (Tg) of deproteinized natural rubber increased from ?62°C to ?46.7°C, when the phenyl group was introduced into the rubber. 相似文献
9.
Lingfei Hu Aijie Cai Zhenzhen Wu Arjan W. Kleij Genping Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(41):14836-14844
A recently reported palladium‐catalyzed allylic substitution of vinyl‐substituted cyclic carbonates (VCCs) with aryl amines represents a rare example of a regio‐ and enantioselective synthesis of α,α‐disubstituted allylic N‐aryl amines. However, the underlying reasons for this unusual selectivity profile remain elusive. In the present work, density functional theory (DFT) calculations in combination with mechanistic control experiments were performed to elucidate in detail this allylic amination manifold and the origin of the regio‐ and enantioselectivity. The combined data show that after oxidative addition of the VCC to Pd0, the nucleophilic attack via an originally proposed outer‐sphere pathway gives, however, the opposite regioisomer compared to the experimental results. Instead, nucleophilic attack of the amine reagent via a unique type of chelation‐assisted, inner‐sphere pathway accounts for the experimentally observed “branched” regioselectivity and high enantio‐control. 相似文献
10.
The activation of C-O bonds in allylic acetates has been accelerated by carrying out the reactions in the presence of platinum complexes associated with ligands. Platinum-catalyzed allylation of aminonaphthalenes with allylic acetates leads to N-allylic aminonaphthalenes in good yields. 相似文献
11.
Beln Rubial Beatrice S. L. Collins Raphael Bigler Stefan Aichhorn Adam Noble Varinder K. Aggarwal 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(5):1380-1384
The one‐pot sequential coupling of benzylamines, boronic esters, and aryl iodides has been investigated. In the presence of an N‐activator, the boronate complex formed from an ortho‐lithiated benzylamine and a boronic ester undergoes stereospecific 1,2‐metalate rearrangement/anti‐SN2′ elimination to form a dearomatized tertiary boronic ester. Treatment with an aryl iodide under palladium catalysis leads to rearomatizing γ‐selective allylic Suzuki–Miyaura cross‐coupling to generate 1,1‐diarylalkanes. When enantioenriched α‐substituted benzylamines are employed, the corresponding 1,1‐diarylalkanes are formed with high stereospecificity. 相似文献
12.
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
13.
Room‐Temperature ortho‐Alkoxylation and ‐Halogenation of N‐Tosylbenzamides by Using Palladium(II)‐Catalyzed CH Activation
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Dr. Florent Péron Dr. Christine Fossey Prof. Dr. Jana Sopkova‐de Oliveira Santos Dr. Thomas Cailly Prof. Dr. Frédéric Fabis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(24):7507-7513
The N‐tosylcarboxamide group can direct the room‐temperature palladium‐catalyzed C?H alkoxylation and halogenation of substituted arenes in a simple and mild procedure. The room‐temperature stoichiometric cyclopalladation of N‐tosylbenzamide was first studied, and the ability of the palladacycle to react with oxidants to form C?X and C?O bonds under mild conditions was demonstrated. The reaction conditions were then adapted to promote room‐temperature ortho‐alkoxylations and ortho‐halogenations of N‐tosylbenzamides using palladium as catalyst. The scope and limitation of both alkoxylations and halogenations was studied and the subsequent functional transformation of the N‐tosylcarboxamide group through nucleophilic additions was evaluated. This methodology offers a simple and mild route to diversely functionalized arenes. 相似文献
14.
The activation of C-O bonds in allylic acetates in water as a suspension medium has been accelerated by carrying out the reactions in the presence of platinum complexes associated with ligands. The platinum-catalyzed allylation of aminonaphthalenes using allylic acetates gave the corresponding N-allylic aminonaphthalenes in good yields. 相似文献
15.
Li Yuan Wulian Chen Jing Li Jianhua Hu Jianjun Yan Dong Yang 《Journal of polymer science. Part A, Polymer chemistry》2012,50(21):4579-4588
A series of well‐defined amphiphilic triblock copolymers, poly(ethylene glycol)‐b‐poly(tert‐butyl acrylate)‐b‐poly(2‐hydroxyethyl methacrylate) (PEG‐b‐PtBA‐b‐PHEMA), were synthesized via successive atom transfer radical polymerization (ATRP). ATRP of tBA was first initiated by PEG‐Br macroinitiator using CuBr/N,N,N′,N″,N′″‐pentamethyldiethylenetriamine as catalytic system to give PEG‐b‐PtBA diblock copolymer. This copolymer was then used as macroinitiator to initiate ATRP of HEMA, which afforded the target triblock copolymer, PEG‐b‐PtBA‐b‐PHEMA. The critical micelle concentrations of obtained amphiphilic triblock copolymers were determined by fluorescence spectroscopy using N‐phenyl‐1‐naphthylamine as probe. The morphology and size of formed aggregates were investigated by transmission electron microscopy and dynamic light scattering, respectively. Finally, an acid‐sensitive PEG‐b‐PtBA‐b‐P(HEMA‐CAD) prodrug via cis‐aconityl linkage between doxorubicin and hydroxyls of triblock copolymers with a high drug loading content up to 38%, was prepared to preliminarily explore the application of triblock copolymer in drug delivery. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
16.
The palladium complex of MgO‐supported melamine‐formaldehyde polymer catalyst was prepared and characterized by X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). The preparation of N‐n‐octyl‐D ‐glucamine was investigated by using this complex as the catalyst. It was found that the palladium complex of MgO‐supported melamine‐formaldehyde polymer has a good catalytic activity for the hydrogenation of n‐octylamine with D ‐glucose to produce N‐n‐octyl‐D ‐glucamine. The effects of additive, solvent, temperature, hydrogen pressure, Pd content in the catalyst and the amount of catalyst on the preparation of N‐n‐octyl‐D ‐glucamine have all been studied. Under the optimum experimental conditions—D ‐glucose, 37.2 mmol; n‐octylamine, 31 mmol; triethylamine, 1.0 ml; ethanol, 60 ml; temperature, 333 K; hydrogen pressure, 1.5 MPa; the amount of the catalyst (Pd content 3.55%, N/Pd molar ratio 12), 0.7 g—the highest yield of N‐n‐octyl‐D ‐glucamine (57.6%) was obtained. XRD results show that melamine‐formaldehyde polymer changed the structure of MgO, and XPS results suggest that coordination bonds were formed between the hexatomic ring and metal atom, and palladium particles were immobilized on the polymer. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
17.
Richard A. Bunce Derrick M. Herron Lu Y. Hale 《Journal of heterocyclic chemistry》2003,40(6):1031-1039
A tandem reduction‐reductive amination reaction has been applied to the synthesis of 3,4‐dihydro‐2H‐1,4‐benzoxazines and 1‐acetyl‐1,2,3,4‐tetrahydroquinoxalines. The nitroketones required for the benzoxazine ring closures were prepared by (A) alkylation of the anion derived from 2‐nitrophenol with an allylic halide or (B) nucleophilic aromatic substitution of an allylic alkoxide on 2‐fluoro‐1‐nitrobenzene followed by ozonolysis. Precursors for the quinoxalines were prepared by alkylation of the anion of 2‐nitroacetanilide with an allylic halide followed by ozonolysis. Catalytic hydrogenation of the nitroketones using 5% palladium‐on‐carbon in methanol then gave the target heterocycles by a reduction‐reductive amination sequence. The N‐methyl derivatives for both ring systems were easily prepared by adding 5‐10 equivalents of aqueous formaldehyde prior to the reduction. The dihydrobenzoxazines were isolated in high yield following purification by chromatographic methods; tetrahydroquinoxalines were isolated in a similar manner and possessed differentiated functionality on the two nitrogens. 相似文献
18.
Hui‐Li Guan Zhi‐Gang Xie Pei‐Biao Zhang Xin Wang Xue‐Si Chen Xian‐Hong Wang Xia‐Bin Jing 《Journal of polymer science. Part A, Polymer chemistry》2005,43(20):4771-4780
An amphiphilic block copolymer, poly(ethylene glycol)‐block‐poly(L ‐lactide‐co‐2‐methyl‐2‐benzoxycarbonyl‐propylene carbonate) [PEG‐b‐P(LA‐co‐MBC)], was synthesized in bulk by the ring‐opening polymerization of L ‐lactide with 2‐methyl‐2‐benzoxycarbonyl‐propylene carbonate (MBC) in the presence of poly(ethylene glycol) as a macroinitiator with diethyl zinc as a catalyst. The subsequent catalytic hydrogenation of PEG‐b‐P(LA‐co‐MBC) with palladium hydroxide on activated charcoal (20%) as a catalyst was carried out to obtain the corresponding linear copolymer poly(ethyleneglycol)‐block‐poly(L ‐lactide‐co‐2‐methyl‐2‐carboxyl‐propylenecarbonate) [PEG‐b‐P(LA‐co‐MCC)] with pendant carboxyl groups. DSC analysis indicated that the glass‐transition temperature (Tg) of PEG‐b‐P(LA‐co‐MBC) decreased with increasing MBC content in the copolymer, and Tg of PEG‐b‐P(LA‐co‐MCC) was higher than that of the corresponding PEG‐b‐P(LA‐co‐MBC). The in vitro degradation rate of PEG‐b‐P(LA‐co‐MCC) in the presence of proteinase K was faster than that of PEG‐b‐P(LA‐co‐MBC), and the cytotoxicity of PEG‐b‐P(LA‐co‐MCC) to chondrocytes from human fetal arthrosis was lower than that of poly(L ‐lactide). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4771–4780, 2005 相似文献
19.
IntroductionWiththefamousDIOPligand ,KaganintroducedtheimportantconceptofC2 symmetryinliganddesign .1However ,itisnotalwaystruethataC2 symmetricligandshouldnecessarilybesuperiortoanon symmetriccoun terpart .Transitionmetal catalyzedallylicalkylationviasymme… 相似文献
20.
Juri Skotnitzki Lukas Spessert Paul Knochel 《Angewandte Chemie (International ed. in English)》2019,58(5):1509-1514
Chiral secondary alkylcopper reagents were prepared from chiral secondary alkyl iodides by a retentive I/Li exchange followed by a retentive transmetalation with CuBr?P(OEt)3. Switching the solvent to THF significantly increased their configurational stability and made these copper reagents suitable for regioselective allylic substitutions. The optically enriched copper species underwent SN2 substitutions with allylic bromides (up to >99 % SN2 regioselectivity). The addition of ZnCl2 and the use of chiral allylic phosphates allowed to switch the regioselectivity towards SN2′ substitution (up to >99 % SN2′ regioselectivity) and to perform highly selective anti‐SN2′ substitutions with absolute control over two adjacent stereocenters. This method was applied in the total synthesis of the three ant pheromones (+)‐lasiol, (+)‐13‐norfaranal, and (+)‐faranal (up to 98:2 dr, 99 % ee). 相似文献