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1.
Heteroarylzirconocene halides were prepared via the oxidative addition of heteroaryl halides to the Negishi reagent ‘Cp2ZrBu2’. The palladium-catalyzed cross-coupling of the in situ generated organozirconium reagents with functionalized aryl and heteroaryl halides proceeded smoothly in the presence of CuCl to produce the cross-coupling products in high yields. 相似文献
2.
A novel method for the synthesis of heteroaryl ketones through one-pot tandem reaction of 1,1-dibromoethenes with 2-amino(thio)phenols promoted by TBAF·3H2O and RuCl3(5%)/air was developed. This novel method includes several reactions in one-pot and utilizes economical yet efficient reagents to generate synthetically and biologically interesting heteroaryl ketones under mild conditions with good efficiency. 相似文献
3.
Ligand‐Free Copper‐Catalyzed Negishi Coupling of Alkyl‐, Aryl‐, and Alkynylzinc Reagents with Heteroaryl Iodides
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Surendra Thapa Arjun Kafle Dr. Santosh K. Gurung Adam Montoya Patrick Riedel Prof. Ramesh Giri 《Angewandte Chemie (International ed. in English)》2015,54(28):8236-8240
Reported herein is an unprecedented ligand‐free copper‐catalyzed cross‐coupling of alkyl‐, aryl‐, and alkynylzinc reagents with heteroaryl iodides. The reaction proceeds at room temperature for the coupling of primary, secondary, and tertiary alkylzinc reagents with heteroaryl iodides without rearrangement. An elevated temperature (100 °C) is required for aryl–heteroaryl and alkynyl–heteroaryl couplings. 相似文献
4.
Direct preparation of various heteroaryl manganese reagents was performed by using highly active manganese (Mn∗) and heteroaryl halides. The resulting organomanganese reagents were coupled with electrophiles such as aryl halides, vinyl halides, and benzoyl chlorides under mild reaction conditions. The corresponding coupling products were obtained in good yields. 相似文献
5.
Generation of Aryl and Heteroaryl Magnesium Reagents in Toluene by Br/Mg or Cl/Mg Exchange
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Dorothée S. Ziegler Prof. Dr. Konstantin Karaghiosoff Prof. Dr. Paul Knochel 《Angewandte Chemie (International ed. in English)》2018,57(22):6701-6704
The alkylmagnesium alkoxide sBuMgOR?LiOR (R=2‐ethylhexyl), which was prepared as a 1.5 m solution in toluene, undergoes very fast Br/Mg exchange with aryl and heteroaryl bromides, producing aryl and heteroaryl magnesium alkoxides (ArMgOR?LiOR) in toluene. These Grignard reagents react with a broad range of electrophiles, including aldehydes, ketones, allyl bromides, acyl chlorides, epoxides, and aziridines, in good yields. Remarkably, the related reagent sBu2Mg?2 LiOR (R=2‐ethylhexyl) undergoes Cl/Mg exchange with various electron‐rich aryl chlorides in toluene, producing diorganomagnesium species of type Ar2Mg?2 LiOR, which react well with aldehydes and allyl bromides. 相似文献
6.
A variety range of functionalized aryl and heteroaryl zinc reagents were efficiently generated by using TMP2Mg·2LiCl (TMP = 2,2,6,6-tetramethylpiperamidyl) in the presence of ZnCl2. The subsequently functionalization gave after reaction with electrophiles the expected polyfunctionalized products in good yields. A detailed study concerned on the point how we found the protocol and how we optimized it was depicted. 相似文献
7.
Ami Uenishi Yuya Nakagawa Hironobu Osumi Prof. Dr. Toshiro Harada 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(15):4896-4905
A highly efficient and practical method for the catalytic enantioselective arylation and heteroarylation of aldehydes with organotitanium reagents, prepared in situ by the reaction of aryl‐ and heteroaryllithium reagents with ClTi(OiPr)3, is described. Titanium complexes derived from DPP‐H8‐BINOL ( 3 d ; DPP=3,5‐diphenylphenyl) and DTBP‐H8‐BINOL ( 3 e ; DTBP=3,5‐di‐tert‐butylphenyl) exhibit excellent catalytic activity in terms of enantioselectivity and turnover efficiency for the transformation, providing diaryl‐, aryl heteroaryl‐, and diheteroarylmethanol derivatives in high enantioselectivity at low catalyst loading (0.2–2 mol %). The reaction begins with a variety of aryl and heteroaryl bromides through their conversion into organolithium intermediates by Br/Li exchange with nBuLi, thus providing straightforward access to a range of enantioenriched alcohols from commercially available starting materials. Various 2‐thienylmethanols can be synthesized enantioselectively by using commercially available 2‐thienyllithium in THF. The reaction can be carried out on a 10 mmol scale at 0.5 mol % catalyst loading, demonstrating its preparative utility. 相似文献
8.
Under very mild reaction conditions, iron or copper nanoparticles efficiently promoted the homocoupling of different Grignard reagents in tetrahydrofuran at room temperature. The nanosized iron or copper particles were generated in situ in a simple and economical way from commercially available FeCl2 or CuCl2, respectively, an excess of lithium powder, and a catalytic amount (5 mol%) of 4,4′-di-tert-butylbiphenyl (DTBB) as electron carrier. The reaction of a series of aryl, heteroaryl, benzyl, and alkenyl Grignard reagents in the presence of a substoichiometric amount of the iron or copper nanoparticles led to the formation of the corresponding homocoupling products in good yield. 相似文献
9.
《Tetrahedron》2014,70(21):3413-3421
Examination of the scope and limitation of the Buchwald–Hartwig cross-coupling reaction in micellar medium is reported. An array of aryl or heteroaryl halides were coupled to diverse nitrogen coupling partners using a combination of [(allyl)PdCl]2 and cBRIDP to afford the corresponding products in moderate to excellent yields. 30 examples are reported, including polar solid and fairly water-soluble organic substrates/reagents. 相似文献
10.
Zhibing Dong Giuliano C. Clososki Prof. Dr. Stefan H. Wunderlich Andreas Unsinn Jinshan Li Prof. Dr. Paul Knochel Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(2):457-468
A wide range of polyfunctional aryl and heteroaryl zinc reagents were efficiently prepared in THF by using (TMP)2Mg ? 2 LiCl (TMP=2,2,6,6‐tetramethylpiperamidyl) in the presence of ZnCl2. The possible pathways of this metalation procedure as well as possible reactive intermediates are discussed. This experimental protocol expands the tolerance of functional groups and allows an efficient zincation of sensitive heterocycles such as quinoxaline or pyrazine. The zincated arenes and heteroarenes react with various electrophiles providing the expected products in 60–95 % yield. 相似文献
11.
Dr. Kilian Colas A. Catarina V. D. dos Santos Dr. Stefanie V. Kohlhepp Dr. Abraham Mendoza 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(9):e202104053
The synthesis of ketones through addition of organometallic reagents to aliphatic carboxylic acids is a straightforward strategy that is limited to organolithium reagents. More desirable Grignard reagents can be activated and controlled with a bulky aniline-derived turbo-Hauser base. This operationally simple procedure allows the straightforward preparation of a variety of aliphatic and perfluoroalkyl ketones alike from functionalized alkyl, aryl and heteroaryl Grignard reagents. 相似文献
12.
Activation of Aryl and Heteroaryl Halides by an Iron(I) Complex Generated in the Reduction of [Fe(acac)3] by PhMgBr: Electron Transfer versus Oxidative Addition
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Dr. Guillaume Lefèvre Dr. Anny Jutand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(16):4796-4805
The mechanism of the reactions of aryl/heteroaryl halides with aryl Grignard reagents catalyzed by [FeIII(acac)3] (acac=acetylacetonate) has been investigated. It is shown that in the presence of excess PhMgBr, [FeIII(acac)3] affords two reduced complexes: [PhFeII(acac)(thf)n] (n=1 or 2) (characterized by 1H NMR and cyclic voltammetry) and [PhFeI(acac)(thf)]? (characterized by cyclic voltammetry, 1H NMR, EPR and DFT). Whereas [PhFeII(acac)(thf)n] does not react with any of the investigated aryl or heteroaryl halides, the FeI complex [PhFeI(acac)(thf)]? reacts with ArX (Ar=Ph, 4‐tolyl; X=I, Br) through an inner‐sphere monoelectronic reduction (promoted by halogen bonding) to afford the corresponding arene ArH together with the Grignard homocoupling product PhPh. In contrast, [PhFeI(acac)(thf)]? reacts with a heteroaryl chloride (2‐chloropyridine) to afford the cross‐coupling product (2‐phenylpyridine) through an oxidative addition/reductive elimination sequence. The mechanism of the reaction of [PhFeI(acac)(thf)]? with the aryl and heteroaryl halides has been explored on the basis of DFT calculations. 相似文献
13.
Dr. Huamin Liang Dr. Qian Wang Dr. Xin Zhou Dr. Rongyi Zhang Dr. Min Zhou Jun Wei Prof. Chuanfa Ni Prof. Jinbo Hu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(19):e202401091
Ligand coupling on hypervalent main group elements has emerged as a pivotal methodology for the synthesis of functionalized N-heteroaromatic compounds in recent years due to the avoidance of transition metals and the mildness of the reaction conditions. In this direction, the reaction of N-heteroaryl sulfur(IV) and N-heteroaryl phosphorus(V) compounds has been well studied. However, the ligand coupling of sulfur(VI) is still underdeveloped and the reaction of alkyl N-heteroarylsulfones is still elusive, which does not match the high status of sulfones as the chemical chameleons in organic synthesis. Here we present a ligand coupling-enabled formal SO2 extrusion of fluoroalkyl 2-azaheteroarylsulfones under the promotion of Grignard reagents, which not only enriches the chemistry of sulfones, but also provides a novel and practical synthetic tool towards N-heteroaromatic fluoroalkylation. 相似文献
14.
A Facile Synthesis of 1,4-Diketones from Organolithium Reagents and N,N,N′,N′-Tetramethylsuccinamide
The reaction of organolithium reagents (alkyl, aryl, heteroaryl) with N,N,N′,N′-tetramethylsuccinamide at 0 °C gives good yields of the corresponding 1,4-diketones. 相似文献
15.
Juliang Zhu 《Tetrahedron letters》2004,45(30):5909-5911
Malononitrile could be utilized as a synthon for the carbonyl moiety via a one-pot process that was initiated via base-mediated SNAr substitution of a heteroaryl halide. Subsequent peracetic acid oxidation of the resultant anion delivered an electrophilic acyl nitrile in situ that readily reacted with added nucleophiles to afford heteroaryl carboxylic acid derivatives. The reaction of the sodium salt of malononitrile with a series of heteroaryl chlorides followed by the subsequent addition of an amine and peracetic acid provided the corresponding heteroaryl amides. 相似文献
16.
A cobalt-bathophenanthroline catalyst has been developed for the direct preparation of a variety of arylindium reagents from the corresponding aryl and heteroaryl bromides in the presence of indium metal and lithium chloride. The thus-formed arylindium reagents undergo efficient palladium-catalyzed cross-coupling reactions with aryl iodides, tolerating various functional groups including hydroxy and free amino groups. 相似文献
17.
Guram AS Wang X Bunel EE Faul MM Larsen RD Martinelli MJ 《The Journal of organic chemistry》2007,72(14):5104-5112
The new air-stable PdCl2[PR2(Ph-R')]2 complexes, readily prepared from commercial reagents, exhibit unique efficiency as catalysts for the Suzuki-Miyaura coupling reactions of a variety of heteroatom-substituted heteroaryl chlorides with a diverse range of aryl/heteroaryl boronic acids. The coupling reactions catalyzed by the new complexes exhibit high product yields (88-99%) and high catalyst turnover numbers (up to 10,000 TON). 相似文献
18.
Pentavalent aryl and heteroaryl bis(catechol) silicates undergo palladium-catalyzed cross-coupling with aryl and heteroaryl triflates in the presence of a fluoride source in excellent yields. These solid, air-stable bis(catechol) silicates are prepared from a high-yielding displacement reaction between catechol and an aryl siloxane in the presence of an amine base. The cross-coupling reaction is tolerant of a wide range of electron-donating and electron-withdrawing groups. Several examples of di-ortho-substituted triflates are successfully coupled with these reagents. 相似文献
19.
Parvin Kumar Meenakshi Sunil Kumar Ashwani Kumar Khalid Hussain Suresh Kumar 《Journal of heterocyclic chemistry》2012,49(5):1243-1249
In this article, an efficient, environmentally benign, one‐pot and simple synthesis of 2‐aryl/heteroarylbenzothiazoles by the reaction of 2‐aminothiophenol and aryl/heteroaryl aldehydes mediated by hypervalent iodine (III) reagents under solvent‐free condition at room temperature is demonstrated. All the reactions were carried out by grinding the reactants (2‐aminothiophenol and aryl/heteroaryl aldehydes) with hypervalent iodine (III) reagents in a mortar with pestle. Phenyliodine bistrifluoroacetate act as an efficient oxidizing reagent in comparison to iodobenzene diacetate in term of reaction time but yields are comparative. The advantages of this protocol are the one‐step procedure, mild reaction conditions, high yields of the products, and no side reactions. 相似文献
20.
Rottlander M Boymond L Berillon L Lepretre A Varchi G Avolio S Laaziri H Queguiner G Ricci A Cahiez G Knochel P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(5):767-770
The iodine-magnesium exchange reaction allows the preparation of polyfunctional aryl, heteroaryl, or alkenyl magnesium reagents at low temperature. These reagents display the typical reactivity of Grignard compounds and undergo various copper-catalyzed reactions such as allylation or 1,4-addition. Using this halogen-metal exchange reaction, it was possible to generate polyfunctional magnesium reagents on the solid phase. 相似文献