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1.
This work reports simple, highly efficient protocol for the oxidation of arylboronic acids. Various arylboronic acids were selectively and completely converted into their corresponding oxidized phenols using H2O2 as an oxidant in presence of catalytic amount of silica chloride. The results show that silica chloride is a suitable and efficient promoter for the oxidation of arylboronic acids. Heterogeneous catalyst, mild reaction conditions, easy availability of the reagent, easy work-up, excellent yield of corresponding phenols, short reaction time and broad substrate scope makes this protocol attractive and a practical alternative to the existing methods. 相似文献
2.
Zhenyu Yang Yuxin Ni Rui Liu Kaixuan Song Shaohui Lin Qinmin Pan 《Tetrahedron letters》2017,58(21):2034-2037
An in situ generated cationic Pd(II)/bipyridine-catalyzed nucleophilic addition of arylboronic acids to N-sulfonyl arylaldimines was developed and optimized, and the reaction was proceeded highly efficiently and conveniently in CH3NO2. A series of arylboronic acids and N-sulfonyl arylaldimines were surveyed, and 12 of 13 examples gave 90~96% yields. 相似文献
3.
4.
N-Arylation of imidazoles with arylboronic acids was efficiently carried out in the presence of a catalytic amount of SiO2-NHC-CuI in methanol at room temperature under base-free reaction conditions. The reactions of a variety of arylboronic acids with imidazoles generated the corresponding products N-arylimidazoles in good to excellent yields. In addition, SiO2-NHC-CuI could be recovered and recycled for six consecutive trials without significant loss of its reactivity. 相似文献
5.
Pd(MeCN)2Cl2/PCy3 was found to be an efficient catalytic system for the Suzuki–Miyaura cross‐couplings of aryl chlorides with arylboronic acids under solvent‐free conditions. Furthermore, the presence of the conventional solvents had deleterious effect on the reaction. In the presence of Pd(MeCN)2Cl2, PCy3, and TBAF (tetra‐n‐butylammonium fluoride), a number of aryl chlorides including heteroaryl chlorides were coupled with arylboronic acids or heteroarylboronic acids smoothly to afford the corresponding products in moderate to excellent yields. 相似文献
6.
Yu-Yang Zhang Huixuan Chen Xiaoding Jiang Hao Liang Xuefeng He Yaqi Zhang Xiangmeng Chen Wenhuan He Yongsu Li Liqin Qiu 《Tetrahedron》2018,74(18):2245-2250
A Ni-catalyzed addition of arylboronic acids to isatins was first developed. The reaction, driven by Ni(acac)2 and dppp as the phosphine ligand, gave 3-aryl-3-hydroxy-2-oxindoles in up to 97% yield. Scopes of benzyl-protected isatins and arylboronic acids were examined. Substituted phenylboronic acids along with fused-ring and heterocyclic boronic acids reacted with isatins smoothly. Preliminary asymmetric catalysis was investigated as well, showing moderate enantioselectivity. The mechanism was also described. 相似文献
7.
A reusable Pd(NH3)2Cl2/cationic 2,2′‐bipyridyl system for the catalysis of the conjugate addition of arylboronic acids to α,β‐unsaturated enones in water under air was developed. Addition of arylboronic acids to both cyclic and acyclic enones progressed smoothly, providing the products in good to high yields, the best result being obtained when HBF4 was used to adjust the pH value to 1.0. After the reaction, the residual aqueous solution could be reused several times, making the reaction greener and reducing wastage of precious metals. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
8.
Bing-Wei Xin 《合成通讯》2013,43(16):2826-2837
A highly efficient aqueous system of PdCl2-catalyzed cross-coupling reaction of arylboronic acid with carboxylic anhydride (Suzuki-type reaction) without the use of phosphine ligands was developed. The reactions went smoothly in acetone/H2O phase to give good yields of aryl ketones in short reaction times (1–3 h) at room temperature in air and were unaffected by the presence of electron-releasing and electron-withdrawing substituents in both the arylboronic acids and carboxylic anhydrides. 相似文献
9.
Chun-Hui Xing 《Tetrahedron letters》2009,50(35):4953-12443
[Rh(COD)Cl]2-catalyzed addition reactions of arylboronic acids with aldehydes, with low Rh(I) catalyst loading, are described. We also found that the reaction of arylboronic acids with α,β-unsaturated aldehydes greatly depends on the solvent and the steric hindrance of the reagents/substrates. 相似文献
10.
Various arylboronic acids reacted with activated alkenes in the presence of [Ni(dppe)Br2], ZnCl2, and H2O in CH3CN at 80 °C to give the corresponding Mizoroki–Heck‐type addition products in good to excellent yields. Furthermore, 1 equivalent of the hydrogenation product of the activated alkene was also produced. By tuning the ligands of the nickel complexes and the reaction conditions, Michael‐type addition was achieved in a very selective manner. Thus, various p‐ and o‐substituted arylboronic acids or alkenylboronic acid reacted smoothly with activated alkenes in CH3CN at 80 °C for 12 h catalyzed by Ni(acac)2, P(o‐anisyl)3, and K2CO3 to give the corresponding Michael‐type addition products in excellent yields. However, for m‐substituted arylboronic acids, the yields of Michael‐type addition products are very low. The cause of this unusual meta‐substitution effect is not clear. By altering the solvent or phosphine ligand, the product yields for m‐substituted arylboronic acids were greatly improved. In contrast to previous results in the literature, the present catalytic reactions required water for Mizoroki–Heck‐type products and dry reaction conditions for Michael‐type addition products. Possible mechanistic pathways for both addition reactions are proposed. 相似文献
11.
氯化钯在氟化四丁基铵中当场生成纳米钯,该钯催化剂在Suzuki-Miyaura交叉偶联反应中显示很高的催化效率。在氯化钯和氟化四丁基铵存在下,许多芳基卤代烃可以顺利与芳基硼酸发生偶联反应,得到中等到高的产率。此外,在Suzuki-Miyaura偶联反应中该氯化钯/氟化四丁基铵催化体系可以回收重复使用多次,并且芳基溴代烃可以在15-60分钟内反应完全。值得指出的是,该反应是在无溶剂、无配体和催化体系可回收重复使用的条件下进行的。这和无配体条件下TBAB中钯催化卤代芳烃与芳基硼酸的Suzuki-Miyaura交叉偶联反应方法。该氯化钯/氟化四丁基铵催化反应的反应机理也进行了讨论。 相似文献
12.
Pd(OAc)2-(±)-tol-BINAP-catalyzed arylation reaction of aromatic aldehydes with arylboronic acids in the absence of CHCl3 is described. 相似文献
13.
An air-stable and easy-to-handle nickel precatalyst, (9-phenanthrenyl)Ni(II)(PPh3)2Cl, was examined for the cross-coupling reactions of aryl tosylates with arylboronic acids. Under the optimized reaction conditions, the catalytic system tolerates a wide range of activated, neutral and deactivated substrates. The selectivity of this cross-coupling reaction towards aryl tosylates and arylboronic acids has been investigated. It is proposed that ligand 1,1′-bis(diphenylphosphino)ferrocene (dppf) plays a key role in the coupling by enforcing a cis geometry in key intermediates and the active Ni(0) species. 相似文献
14.
Silylated functionalized arylboronic acids were converted into corresponding iodinated arylboronic acids in good yields via the electrophilic ipso-desilylation effected with iodine chloride in refluxing CHCl3. Disilylated arylboronic acids were susceptible to diiodination. In addition, the structural characterization and reactivity of a novel sterically hindered ortho-silylated diarylborinic ester were reported. The potential of selected iodinated phenylboronic acids as monomers for the Suzuki-Miyaura cross-coupling polymerization was demonstrated. 相似文献
15.
Recyclable and reusable Pd(OAc)2/PPh3/PEG‐2000 system for homocoupling reaction of arylboronic acids under air without base
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A stable and efficient Pd(OAc)2/PPh3/PEG‐2000 catalytic system for homocoupling of arylboronic acids has been developed. In the presence of Pd(OAc)2 and PPh3, the homocoupling reaction of arylboronic acids was carried out smoothly in PEG‐2000 at 70 °C under air without base to afford a variety of symmetric biaryls in good to excellent yields. The isolation of the products was readily performed by extraction with diethyl ether, and the Pd(OAc)2/PPh3/PEG‐2000 system could be easily recycled and reused six times without significant loss of catalytic activity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
16.
The Suzuki-Miyaura reaction of 1,4-dibromo-2-fluorobenzene with two equivalents of arylboronic acids gave fluorinated para-terphenyls. The reaction with 1 equiv of arylboronic acid resulted in site-selective formation of biphenyls. The one-pot reaction of 1,4-dibromo-2-fluorobenzene with two different arylboronic acids afforded fluorinated para-terphenyls containing two different terminal aryl groups. 相似文献
17.
Ya-Zhen DuanMin-Zhi Deng 《Tetrahedron letters》2003,44(16):3423-3426
Aryl amides were synthesized by the palladium catalyzed cross-coupling reaction of α-bromoacetamides with arylboronic acids in good yields. Both electron-donating and electron-withdrawing substituents on the aromatic ring are found to be compatible. The addition of Cu2O and PPh3 was found to be essential for good reaction yields. 相似文献
18.
We report the magnetic recoverable catalyst (CuFe2O4) catalyzed multicomponent reaction of aliphatic amines, formaldehyde, arylboronic acids and alkynyl carboxylic acids for the synthesis of diverse propargylamines at room temperature. 相似文献
19.
The Pd-catalysed conjugate addition of arylboronic acids to α,β-unsaturated cyclic ketones was studied under controlled microwave irradiation conditions. A variety of catalysts, bases and
solvents was explored in order to achieve optimum yields in the shortest possible reaction time. Under optimised conditions
(Pd(OAc)2/2,2′-bipyridine and KF in a mixture of toluene, water, and acetic acid and 10 min microwave irradiation), a range of arylboronic
acids was successfully added to several cyclic enones. With chiral phosphane ligands, a promising enantioselectivity was obtained
(85 % ee). 相似文献
20.
A highly efficient, convenient, and environmentally friendly protocol was developed for the PdCl2-catalyzed ligandless and additive-free Suzuki reaction of aryl bromides with arylboronic acids in water/ethanol. 相似文献