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1.
1-(p-Nitrophenylsulfonyl)buta-1,3-diene reacts with arenediazonium chlorides in aqueous acetone in the presence of catalytic amounts of CuCl2·2H2O to form 1-(p-nitrophenylsulfonyl)-4-aryl-3-chloro-1-bu- tenes. In the presence of SO2, 1-(p-nitrophenylsulfonyl)buta-1,3-diene does not react with arenediazonium chlorides. 相似文献
2.
Renata A. Balaguez Vanessa Gentil RicordiCamilo S. Freitas Gelson PerinRicardo F. Schumacher Diego Alves 《Tetrahedron letters》2014
We describe here a simple and catalyst-free method to synthesize diaryl selenides by reaction of arenediazonium tetrafluoroborate salts with arylselenols, generated in situ by using diaryl diselenides and hypophosphorous acid (H3PO2), using THF as solvent. This is a direct nucleophilic aromatic substitution (SNAr) reaction performed with diaryl diselenides and arenediazonium salts bearing electron-withdrawing and electron-donating groups affording the corresponding diaryl selenides in moderated to good yields. 相似文献
3.
Chloroarylation of unsaturated compounds with arenediazonium chlorides in the presence of CuCl2 as catalyst involves intermediate formation of arenediazonium tetrachlorocuprates(II) [ArN2
+]2 CuCl4
2-. A procedure for preparative isolation of these intermediates was developed, and they were shown to be efficient arylating agents. Reactions of [ArN2
+]2 CuCl4
2- with unsaturated compounds gave the corresponding Meerwein products; a mechanism was proposed for these reactions. In polar solvents arenediazonium tetra- chlorocuprates(II) are converted into chloroarenes, presumably through a cyclic transition state. 相似文献
4.
The scope of the Heck arylation of enol ethers with arenediazonium salts: a new approach to the synthesis of flavonoids 总被引:1,自引:0,他引:1
Angelo H.L. Machado 《Tetrahedron letters》2009,50(11):1222-9268
The scope of the Heck arylation of cyclic and acyclic enol ethers with arenediazonium salts was evaluated. Arylation of 2,3-dihydrofuran yielded 2-aryl-2,5-dihydrofurans as the major adducts (>99:1) except when using n-Bu4NHSO4 as additive or 4-NO2PhN2BF4 as arenediazonium salt. 2,3-Dihydropyran provided mixtures of the three possible isomeric Heck adducts. Arylation of n-butylvinylether with arenediazonium bearing electron-donating groups resulted in substituted acetophenones as almost exclusive products in good overall yields. Substituted 4H-chromenes provided 2-aryl-2H-chromenes in moderate yield when applying the Pd(OAc)2/2,6-di-t-butyl-4-methylpyridine catalytic system, which were applied in the synthesis of flavonoids. 相似文献
5.
Grishchuk B. D. Baranovskii V. S. Gorbovoi P. M. Ganushchak N. I. 《Russian Journal of General Chemistry》2003,73(6):957-960
The reactions of arenediazonium tetrafluoroborates with N,N-methylenediacrylamide in H2O-DMF (1:3) and H2O-DMSO (1:4) in the presence of thiocyanate anions involve thiocyanatoarylation by one or two multiple bonds to give [(3-aryl-2-thiocyanatopropionylamino)methyl]-2-acryalmides and N,N-methylenebis(2-thiocyanato-3-arylpropionamides). 相似文献
6.
A novel experimental procedure to obtain α-benzyl-β-keto esters from the Heck reaction between arenediazonium tetrafluoroborate salts and Baylis-Hillman (BH) adducts in the presence of Pd(OAc)2 as catalyst is described. The methodology is simple, straightforward and the use of arenediazonium salts as opposed to conventional arylhalides/triflates over the usual Heck reaction is highlighted. 相似文献
7.
《Tetrahedron letters》2014,55(50):6779-6783
A facile hydroiodination of alkynes using readily-available reagents such as I2, PPh3, and H2O has been developed. This is extended to the one-pot synthesis of trisubstituted alkenes from alkynes via iodoalkenes using Pd-catalyzed cross-coupling and related methods such as the Suzuki–Miyaura cross-coupling, Sonogashira cross-coupling reaction, and Mizoroki–Heck reaction. 相似文献
8.
The preparation of several novel lariat ethers (macrocyclic crown polyethers having sidearms bearing pendant donor groups) is reported, These compounds are ethers derived from known 2-hydroxymethyl-15-crown-5 or -21-crown-7. The sidearms Include 2-aminophenyl, 2,4-diaminophenyl, 2-nitrophenyl, 2-(3'-nitrobiphenyl), and 2-(3'-aminobiphenyl). In several cases, the amino groups were converted into ammonium salts which showed substantial stabilization by intramolecular hydrogen bonding. Likewise, an -NH2+.,BF3- complex showed evidence of intramolecular hydrogen bonding. Diazotization of the aminobiphenyl residue produced an arenediazonium cation which underwent intramolecular crown complexation, as judged by infrared spectroscopic studies to form what we call an “ostrich molecule” complex. Addition of N,N-dimethylaniline to the intramolecular arenediazonium cation complex afforded an azo compound, but europium shift reagent studies showed clearly that the diazonium cation reacted outside the macroring. 相似文献
9.
Changge Zheng Yang Liu Jianquan Hong Shuai Huang Wei Zhang Yupeng Yang Ge Fang 《Tetrahedron letters》2019,60(21):1404-1407
An efficient method for trifluoromethylthiolation of arenediazonium salts has been developed in mild conditions with a stable and convenient AgSCF3. It provides a straightforward and convenient way for the synthesis of trifluoromethylthiolated compound from diazonium salts in moderate to good yields. 相似文献
10.
The Suzuki-Miyaura cross-coupling of arenediazonium tetrafluoroborate salts with boronic acid partners catalyzed by Pd(0)/C is described as a practical and efficient alternative to classical homogeneous conditions. Reactions conducted in alcoholic solvents proved to be extremely fast using mild conditions. Additionally, we developed a chemoselective double Suzuki-Miyaura cross-coupling in a single reaction vessel allowing the synthesis of unsymmetrical terphenyls. 相似文献
11.
《Mendeleev Communications》2022,32(6):801-803
Metal–organic framework (MOF) composite, viz. Cu-BTC@Fe3O4 (BTC is 1,3,5-benzenetricarboxylate), was prepared and utilized for the synthesis of aryl α-chlorobenzyl ketones from arenediazonium salts and arylacetylenes in moderate to good yields. This reaction proceeded via a radical domino process. The catalyst could be readily recovered with an external permanent magnet, with slight decrease in its activity after successive six runs. 相似文献
12.
Shengqiang Wang Hongtao Lu Jingya Li Dapeng Zou Yusheng Wu Yangjie Wu 《Tetrahedron letters》2017,58(12):1107-1111
An efficient and general protocol for the decarboxylative cross-coupling of pyridazine-3-carboxylic acids with aryl-bromides has been described. This method provides a new avenue for the synthesis of 3-arylpyridazines via decarboxylative cross-coupling strategy by employing the dual-catalyst system of Pd(PPh3)4/Cu2O in the presence of Li2CO3 at 160 °C in DMA. 相似文献
13.
《中国化学》2018,36(3):206-212
A copper‐mediated di‐ and monofluoromethanesulfonylation of arenediazonium tetrafluoroborates using di‐ and monofluoromethanesulfinate reagents provides aryl difluoromethyl (or monofluoromethyl) sulfones in good yields. It was found that the relative reactivity of these sodium fluoroalkanesulfinates in the present reactions decreases in the following order: CH2FSO2Na > CF2HSO2Na > CF3SO2Na. 相似文献
14.
Ricardo F. Schumacher 《Tetrahedron letters》2008,49(3):538-542
3-Iodoselenophene derivatives undergo a direct Negishi cross-coupling reaction with several organozinc compounds in the presence of a catalytic amount of Pd(PPh3)4 in THF at room temperature. This cross-coupling reaction proceeded cleanly under mild conditions and permitted the formation of polyaromatic compounds in good yields. 相似文献
15.
Copper‐Catalyzed Arylation of Nitrogen Heterocycles from Anilines under Ligand‐Free Conditions
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Dounia Toummini Dr. Anis Tlili Julien Bergès Prof. Fouad Ouazzani Dr. Marc Taillefer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(45):14619-14623
The arylation of pyrazole and derivatives can be achieved by coupling arenediazonium species (formed in situ from anilines) by using a catalytic system that employs low‐toxicity and inexpensive copper metal under very mild and ligand‐free conditions (T=20 °C). From other nitrogen heterocycles, the presence of an additive (NBu4I) significantly improves the efficiency of the catalytic system. These results represent the first examples of C?N bond formation from arenediazonium species. 相似文献
16.
To introduce the biaryl structure as a triazine functionality, we have developed a new synthetic route via the Suzuki cross-coupling reaction of resin-bound chlorotriazines. The Suzuki cross-coupling reaction was achieved using various arylboronic acids, Pd(PPh3)4, Cs2CO3, and dioxane. With the integration of this chemistry and our previous orthogonal methodology, the triazine library is greatly expanded to a biaryl scaffold. 相似文献
17.
A practical copper-catalyzed N-arylation of NH-containing heterocycles with arenediazonium tetrafluoroborates has been developed using CuCl as catalyst and K2CO3 as additive under ligand-free conditions. This reaction system has wide substrate scope including imides, 1H-pyrazole, 1H-tetrazoles, 1,2-benzisothiazol-3(2H)-one, and related sulfonamides and gives moderate to excellent yields (up to 95%) of the desired products. This strategy is very general, simple, environmentally friendly, and tolerant of oxygen. 相似文献
18.
Adriane Sperança 《Tetrahedron letters》2010,51(1):36-391
3-Iodo-4-chalcogen-2H-benzopyran derivatives underwent a direct Sonogashira cross-coupling reaction with several terminal alkynes in the presence of a catalytic amount of Pd(PPh3)2Cl2 with CuI as a co-catalyst, using Et3N as base and solvent. This cross-coupling reaction proceeded cleanly under mild conditions and was performed with propargylic alcohols, propargylic ethers, as well as alkyl and aryl alkynes, furnishing the correspondent 3-alkynyl-4-chalcogen-2H-benzopyrans in good yields. 相似文献
19.
Triarylstibines react with iodobenzene diacetate in dichloromethane to afford triarylantimony(V) diacetates. The cross-coupling and carbonylative cross-coupling of triarylantimony(V) diacetates and dichlorides with organostannanes was accomplished in the presence of PdCl2 (5 mol%) in CH3CN at room temperature. 相似文献
20.
Vinyl p-methylphenyl ether in aqueous acetone at pH 3-4 in the presence of catalytic amounts of copper(II) chloride reacts with arenediazonium chlorides to form arylacetaldehydes. Vinyl p-nitrophenyl ether under the same conditions fails to react with arenediazonium chlorides. 相似文献