- Nickel(II)/N-Heterocyclic Carbene Catalyzed Desulfinylative Arylation by C?S Cleavage of Aryl Sulfoxides with Phenylboronic Acids
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Suzuki-Miyaura coupling of haloarenes is the most widely used protocol for the synthesis of biphenyls. Organosulfur compounds are promising electrophiles since they are abundant in nature and versatile in organic synthesis. We report here the desulfinylative Suzuki-Miyaura coupling of aryl sulfoxides with phenylboronic acids using bench-stable nickel/5-(2,4,6-triisopropylphenyl)imidazolylidene[1,5-a]pyridines as the catalyst. The ligands are readily prepared from common commercial chemicals. The method is applicable to both symmetric and unsymmetric aryl sulfoxides, and a range of biphenyls bearing various functional groups were obtained in up to 94% yield. (Figure presented.).
- Yi, Xiaowen,Chen, Kai,Guo, Junjun,Chen, Wei,Chen, Wanzhi
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supporting information
p. 4373 - 4377
(2020/07/27)
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- Synthesis of Biaryls via Decarbonylative Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling of Aryl Anhydrides
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Transition metal-catalyzed cross-couplings have been widely employed in the synthesis of many important molecules in synthetic chemistry for the construction of diverse C-C bonds. Conventional cross-coupling reactions require active electrophilic coupling partners, such as organohalides or sulfonates, which are not environmentally friendly enough. Herein, we disclose the first nickel-catalyzed Suzuki-Miyaura cross-coupling of aryl anhydrides and arylboronic acids for the synthesis of biaryls in a decarbonylation manner. The reaction tolerates a wide range of electron-withdrawing, electron-neutral, and electron-donating substituents in this process.
- Zhou, Jing-Ya,Liu, Rui-Qing,Wang, Cheng-Yi,Zhu, Yong-Ming
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p. 14149 - 14157
(2020/11/13)
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- Small Phosphine Ligands Enable Selective Oxidative Addition of Ar-O over Ar-Cl Bonds at Nickel(0)
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Current methods for Suzuki-Miyaura couplings of nontriflate phenol derivatives are limited by their intolerance of halides including aryl chlorides. This is because Ni(0) and Pd(0) often undergo oxidative addition of organohalides at a similar or faster rate than most Ar-O bonds. DFT and stoichiometric oxidative addition studies demonstrate that small phosphines, in particular PMe3, are unique in promoting preferential reaction of Ni(0) with aryl tosylates and other C-O bonds in the presence of aryl chlorides. This selectivity was exploited in the first Ni-catalyzed C-O-selective Suzuki-Miyaura coupling of chlorinated phenol derivatives where the oxygen-containing leaving group is not a fluorinated sulfonate such as triflate. Computational studies suggest that the origin of divergent selectivity between PMe3 and other phosphines differs from prior examples of ligand-controlled chemodivergent cross-couplings. PMe3 effects selective reaction at tosylate due to both electronic and steric factors. A close interaction between nickel and a sulfonyl oxygen of tosylate during oxidative addition is critical to the observed selectivity.
- Entz, Emily D.,Hooker, Leidy V.,Neufeldt, Sharon R.,Russell, John E. A.
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p. 15454 - 15463
(2020/10/18)
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- Exploring the coordination confinement effect of divalent palladium/zero palladium doped polyaniline-networking: As an excellent-performance nanocomposite catalyst for C-C coupling reactions
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A pre-formed catalyst Pd2+/PANI composite for C-C coupling reaction was synthesized by combining the self-stabilized dispersion polymerization method with the in-situ composite material. Experiments have confirmed that the relatively high reduced structure (75%) in the polyaniline carrier is more favorable for the coupling reaction. Raman spectroscopy, solid nuclear magnetic, and X-ray photoelectron spectroscopy were performed to characterize the structures. The pre-formed catalyst has uniform coordination of divalent palladium and nitrogen in different valence states of the carrier polyaniline, which shows a good synergistic effect in the catalytic Ullmann reaction, and greatly reduces the use of reducing agents such as hydrazine hydrate. Compared with other studies, we analyzed the catalytic reaction mechanism in detail through real-time online infrared and XPS characterization. The results show that the divalent palladium in the catalyst and the zero-valent palladium generated by the in-situ reaction synergistically promote the reaction, while the polyaniline support acts as a stabilizer and dispersant, which prevents the agglomeration of the metal particles and prolongs increased catalyst life. The prepared Pd2+/PANI composites will become the most attractive alternative to traditional organic materials due to their wide applicability, high catalytic activity, stable recycling and relatively low price. This work provides a new theoretical basis for the understanding of the essential driving force of PANI catalytic activity and the cognition of the micro mechanism of action.
- Liang, Yanping,Liu, Wanyi,Song, Manrong,Sun, Yanyan,Wang, Gang,Wu, Zhiqiang,Zhan, Haijuan
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p. 177 - 188
(2020/03/17)
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- Transition-Metal-Free Cross-Coupling of Aryl Halides with Arylstannanes
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Transition-metal-free LiCl-promoted cross-coupling reactions of tetraphenyltin, trichlorophenyl-, dichlorodiphenyl-, and chlorotriphenylstannanes with aryl halides in DMF provided access to biaryls in good to high yields. Up to four phenyl groups were transferred from the organostannanes substrates. The aryls bearing electron-withdrawing groups in either halides or organotin substrates gave coupling products in higher yields. The methodology has been applied for the efficient synthesis of ipriflavones.
- He, Qing,Wang, Liwen,Liang, Yong,Zhang, Zunting,Wnuk, Stanislaw F.
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p. 9422 - 9427
(2016/10/17)
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- Agglomeration of Pd0 nanoparticles causing different catalytic activities of Suzuki carbonylative cross-coupling reactions catalyzed by PdII and Pd0 immobilized on dopamine-functionalized magnetite nanoparticles
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Solvent-dispersible magnetite nanoparticles (Fe3O4) end-functionalized with amino groups were successfully prepared by a facile one-pot template-free method to immobilize PdII and Pd0 using a metal adsorption and reduction procedure. They were characterized by TEM, XRD, XPS, FT-IR and VSM. Interestingly, the PdII catalyst exhibited better catalytic activity for carbonylative cross-coupling reactions than the Pd0 catalyst. According to the catalytic activities of a variety of arylboronic acids and aryl iodides catalyzed by two kinds of Pd catalysts, the proposed reaction mechanism of Suzuki carbonylative cross-coupling reactions using the Pd catalyst was also inferred. More importantly, agglomeration of Pd0 nanoparticles was obviously observed in the TEM images of the catalysts after reactions. Therefore, agglomeration of Pd0 nanoparticles should be considered as a significant reason for different catalytic activities of the reactions catalyzed by immobilized PdII and Pd0 catalysts. Furthermore, the PdII catalyst revealed high efficiency and stability during recycling stages.
- Long, Yu,Liang, Kun,Niu, Jianrui,Tong, Xin,Yuan, Bing,Ma, Jiantai
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p. 2988 - 2996
(2015/04/14)
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- Palladium and copper-catalyzed ligand-free coupling of phenylhydrazines in water
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An efficient protocol has been developed for the synthesis of biaryls via Pd/Cu catalyzed coupling of phenylhydrazines in water. Homo and cross couplings were successfully achieved in a ligand-free catalytic system, at room temperature with water as sole reaction medium. This journal is
- Chauhan, Parul,Ravi, Makthala,Singh, Shikha,Raju, Kanumuri S. R.,Bajpai, Vikas,Kumar, Brijesh,Wahajuddin,Yadav, Prem. P.
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p. 43336 - 43340
(2015/02/19)
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- Direct exchange of a ketone methyl or aryl group to another aryl group through ciC bond activation assisted by rhodium chelation
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Swapped: Commercially available quinolinone derivatives (1 or 2, see scheme) were reacted with arylboronic acids in the presence of a RhI complex to give aryl(quinolin-8-yl)methanone products 3 in medium to good yields. A mechanism that involves the in situ oxidation of RhI to RhIII by O2 in the presence of CuI was proposed. Copyright
- Wang, Jingjing,Chen, Weiqiang,Zuo, Sujing,Liu, Lu,Zhang, Xinrui,Wang, Jianhui
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supporting information
p. 12334 - 12338
(2013/02/23)
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- Preparation of unsymmetrical biaryls by pd(II)-catalyzed cross-coupling of aryl iodides
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The Ullmann homo-and cross-couplings of aryl iodides are carried out to afford symmetrical and unsymmetrical biaryls in moderate to good yields in a catalytic system of Pd(OAc)2/K2CO3/MeCOEt. The high selectivity of unsymmetrical biaryl products in cross-couplings mainly depends on the reactivity difference between two iodoarene substrates and their employed ratios.
- Wang, Liqiang,Lu, Wenjun
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supporting information; experimental part
p. 1079 - 1082
(2009/07/25)
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- A new palladium catalyzed protocol for atom-efficient cross-coupling reactions of?triarylbismuths with aryl halides and triflates
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A new palladium catalyzed protocol for an atom-efficient cross-coupling reaction of triarylbismuths with aryl halides and triflates has been described. The palladium catalytic system with Cs2CO3 base was found to be very efficient in DMA solvent to furnish excellent yields of cross-coupled functionalized biaryls in short reaction times.
- Rao, Maddali L.N.,Jadhav, Deepak N.,Banerjee, Debasis
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p. 5762 - 5772
(2008/09/21)
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- Phosphine oxides as stabilizing ligands for the palladium-catalyzed cross-coupling of potassium aryldimethylsilanolates
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The palladium-catalyzed cross-coupling reaction of potassium (4-methoxyphenyl)dimethylsilanolate (K+1-) with aryl bromides has been demonstrated using triphenylphosphine oxide as a stabilizing ligand. Unsymmetrical biaryls can be prepared from a variety of aryl bromides in good yield with short reaction times. Qualitative kinetic studies compared effects of different phosphine oxides on the rate of cross-coupling and established the beneficial effect of these ligands in the reaction of electron-rich arylsilanolates. The improved yield and reproducibility of the cross-coupling of several bromides was demonstrated by direct comparison of reactions performed with and without triphenylphosphine oxide under non-rigorous exclusion of oxygen.
- Denmark, Scott E.,Smith, Russell C.,Tymonko, Steven A.
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p. 5730 - 5738
(2008/02/07)
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- Anchored palladium bipyridyl complex in nanosized MCM-41: a recyclable and efficient catalyst for the Kumada-Corriu reaction
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A palladium bipyridyl complex anchored onto nanosized mesoporous silica MCM-41 catalyzed the cross-coupling of aryl iodides or bromides with Grignard reagents to provide the corresponding biaryls in high yields. The reaction proceeded smoothly with an equal molar amount of substrate and Grignard reagent in the presence of 0.2-0.02 mol % of catalyst in THF at 50 °C or under refluxing conditions. The catalyst prepared may be used in a very low percentage, recovered after reaction, and re-used.
- Tsai, Fu-Yu,Lin, Bo-Nan,Chen, Ming-Jie,Mou, Chung-Yuan,Liu, Shiuh-Tzung
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p. 4304 - 4309
(2007/10/03)
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- 2-Methoxy-4-nitrobenzenediazonium salt as a practical diazonium-transfer agent for primary arylamines via tautomerism of 1,3-diaryltriazenes: Deaminative iodination and arylation of arylamines without direct diazotization
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1,3-Diaryltriazenes, prepared from a 2-methoxy-4-nitrobenzenediazonium salt and primary arylamines, exist as "azo-transfer" tautomers in which the 2-methoxy-4-nitrophenyl group is present on the saturated nitrogen atom and forms a hydrogen bond between the 2-methoxy group and the N-H moiety. The synthetic utility of the diazonium salt as a practical diazonium-transfer agent for primary arylamines via tautomerism of the 1,3-diaryltriazenes has been demonstrated by the deaminative iodination and arylation of the arylamines without direct diazotization. The starting 2-methoxy-4-nitrophenylamine can be easily recovered after the reactions.
- Saeki, Tomoyuki,Son, Eun-Cheol,Tamao, Kohei
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p. 1654 - 1658
(2007/10/03)
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- Photolysis of 4-Methoxyphenyl Aryl Alkylphosphonates
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UV irradiation of bis(4-methoxyphenyl) methylphosphonate 1a in methanol gave 4,4'-dimethoxybiphenyl 2a as the main product through an intramolecular excimer.With 4-cyanophenyl-4-methoxyphenyl methylphosphonate 1b 4-cyano-4'-methoxybiphenyl 2c and 4-cyano-2-(4'-methoxyphenyl)phenyl methylphosphonate 4b were obtained through an intramolecular exciplex. 3-Cyanophenyl-4-methoxyphenyl methyl phosphonate 1c gave only 3-cyano-4'-methoxybiphenyl 2f.Methyl 4-methoxyphenyl 4-chlorobenzylphosphonate 5a gave dimethyl 4-chlorobenzyl 2-(4'-methoxyphenyl)phosphonate and dimethyl 2-(4'-methoxyphenyl)benzylphosphonate.
- Nakamura, Mitsunobu,Sawasaki, Kouiti,Okamoto, Yoshiki,Takamuku, Setsuo
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p. 141 - 146
(2007/10/02)
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