2920-38-9Relevant academic research and scientific papers
Abnormal N-heterocyclic carbene palladium complex: Living catalyst for activation of aryl chlorides in Suzuki-Miyaura cross coupling
Sau, Samaresh Chandra,Santra, Subhankar,Sen, Tamal K.,Mandal, Swadhin K.,Koley, Debasis
, p. 555 - 557 (2012)
Palladium complexes bearing abnormal N-heterocyclic carbene were used as catalysts in Suzuki-Miyaura cross coupling of aryl chlorides at 25 °C. The catalyst remained active for 10 successive catalytic runs and can activate 4-chlorotoluene at 25 °C with 0.01 mol% catalyst loading resulting in a TON of 9500 within 6 h.
PVP-stabilized palladium nanoparticles electrochemically obtained as effective catalysts in aqueous medium Suzuki-Miyaura reaction
Uberman, Paula M.,Martin, Sandra E.,Perez, Luis A.,Lacconi, Gabriela I.
, p. 245 - 253,9 (2012)
In this paper the synthesis of stable palladium nanoparticles (PdNPs) by electrochemical methods at room temperature is reported. Direct electroreduction of H2PdCl4 aqueous solution in the presence of poly-(N-vinyl-2-pirrolydone) (PVP) onto platinum electrodes was performed by the application of a constant current density pulse. By simultaneous stirring of the electrolyte, the NPs formed on the electrode surface were stabilized with PVP in the solution. The resulting PdNPs were characterized by transmission electron microscopy and the total content of palladium was analytically determined by atomic absorption measurements. The average size of the NPs (in the range of 10-22 nm) was tuned by changing the current density applied. The PdNPs prepared by this methodology exhibited highly efficient catalytic activity on Suzuki-Miyaura coupling reaction in aqueous medium. Particularly high turnover numbers (TON up to 104-105) were achieved by these PVP-stabilized PdNPs with aryl iodides and bromides.
CuBr/proline-catalyzed cross-coupling of unactivated benzene with aryl halides
Liu, Wei,Hou, Fanyi
, p. 368 - 371 (2015)
Direct C-H arylation of unactivated benzene with aryl halides was achieved using a readily available copper catalyst. The reaction was carried out at 80 °C, using CuBr as catalyst, proline as ligand and t-BuOK as base. This radical cross-coupling reaction between unactivated benzene and aryl iodides proceeds via homolytic aromatic substitution and offers an efficient method for the synthesis of various biaryls in good to excellent yields.
Fe3O4@SiO2@ l -arginine@Pd(0): A new magnetically retrievable heterogeneous nanocatalyst with high efficiency for C-C bond formation
Ghorbani-Choghamarani, Arash,Azadi, Gouhar
, p. 247 - 252 (2016)
The surface of Fe3O4@SiO2 nanoparticles was modified using l-arginine as a green and available amino acid to trap palladium nanoparticles through a strong interaction between the metal nanoparticles and functional groups of the amino acid. The proposed green synthetic method takes advantage of nontoxic reagents through a simple procedure. Characterization of Fe3O4@SiO2@l-arginine@Pd(0) was done using Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, vibrating sample magnetometry and inductively coupled plasma analysis. The catalytic activity of Fe3O4@SiO2@l-arginine@Pd(0) as a new nanocatalyst was investigated in C-C coupling reactions. Waste-free, use of green medium, efficient synthesis leading to high yield of products, eco-friendly and economic catalyst, excellent reusability of the nanocatalyst and short reaction time are the main advantages of the method presented.
Bis(imino)pyridine palladium(II) complexes as efficient catalysts for the Suzuki-Miyaura reaction in water
Liu, Ping,Yan, Mei,He, Ren
, p. 131 - 134 (2010)
Bis(imino)pyridine palladium(II) complexes 3 and 4 of type [PdCl(L)PF 6] are found to be efficient catalysts for Suzuki-Miyaura reactions of aryl halides and arylboronic acids. The reactions proceed smoothly to generate the corresponding biaryl compounds in moderate to excellent yields. The synthesis of various fluorinated biphenyl derivatives was successfully achieved by the complex 4 catalyzed the Suzuki-Miyaura reaction in the presence of surfactants bearing a long alkyl chain. Copyright
LIQUID CRYSTALLINE 4-ALKYLAMINO-4 prime -CYANOBIPHENYLS.
Ruoliene,Adomenas,Tubelyte,Seskauskas,Grozhik
, p. 211 - 216 (1981)
A number of mesomorphic 4-alkylamino-4 prime -alkylamino-4 prime -cyanobiphenyls were synthesized. These compounds melt at higher temperatures and form nematic and smectic. A state with higher thermal stability than that of analogaous 4-alkoxy-4 prime -cyanobiphenyls. 4-Octylamino-4 prime -cyanobiphenyl is characterized by a significantly higher dielectric anisotropy in comparison with its 4-octyloxy analog, in the nematic state, but not in the smectic state. Density data and refractometric indices of several 4 substituted 4 prime -cyanobiphenyls are presented; refractometric data confirm higher polarizability of 4-alkylamino-4 prime -cyanobiphenyls as compared with their 4-alkoxy analogs.
Fullerene-ionic-liquid conjugates: A new class of hybrid materials with unprecedented properties
Campisciano, Vincenzo,Parola, Valeria La,Liotta, Leonarda F.,Giacalone, Francesco,Gruttadauria, Michelangelo
, p. 3327 - 3334 (2015)
A modular approach has been followed for the synthesis of a series of fullerene-ionic-liquid (IL) hybrids in which the number of IL moieties (two or twelve), anion, and cation have been varied. The combination of C60 and IL give rise to new unique propert
Effect of Alkyl Structures on the Anti-stacking and Anchoring of Pd/Diamine-Functionalized Graphene Nanoparticles in Application in Suzuki Reaction
Tian, Yinbing,Tang, Zijie,Ru, Yu,Wang, Yuanyuan,Dai, Liyi
, p. 2745 - 2754 (2021)
Three diamines (1,8-diaminooctane/p-phenylenediamine/biphenylenediamine) with different alkyl groups were used to synthesize the functionalized graphene networks. Pd as the common metal catalyst was used to explore the effects of alkyl types of diamines on anti-stacking, metal anchoring ability of functional graphene and hence the catalytic performance. The results were discussed by characterization of the material and its catalytic properties. All catalysts showed excellent catalytic performance on the Suzuki cross-coupling reaction with a high yield of up to 100%. The p-phenylenediamine and biphenylenediamine functionalized graphene with larger specific surface area was beneficial to improve the stability of the graphene catalyst and maintain good catalytic activity after 5 cycles. The Pd nanoparticles in 1,8-octanediamine materials have smaller size and a smaller loading with the same or even better catalytic performance than p-phenylenediamine, biphenylenediamine materials, due to the stronger electron donating ability of N of octanediamine than that of p-phenylenediamine.
A highly sensitive fluorescence method reveals the presence of palladium in a cross-coupling reaction mixture not treated with transition metals
Inamoto, Kiyofumi,Campbell, Laura D.,Doi, Takayuki,Koide, Kazunori
, p. 3147 - 3148 (2012)
We previously reported a Suzuki-Miyaura coupling in dimethyl carbonate without adding additional transition metals. Here, we show an analysis of the reaction mixture that revealed the presence of palladium using a fluorogenic Tsuji-Trost reaction.
The recyclable cyclopalladated ferrocenylimine self-assembly catalytic film and investigation of its role in the mechanism of heterogeneous catalysis
Fu, Zhihua,Li, Tiesheng,He, Xiaohang,Liu, Jie,Wu, Yangjie
, p. 26413 - 26420 (2014)
An efficient, reusable and stable catalyst nano-sheet film (Si-CDI-Pd) was developed, in which cyclopalladated ferrocenylimines were grafted onto silicon, glass and quartz surfaces by covalent bonds. Water contact angle, ultraviolet-visible spectroscopy (UV-Vis), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), low-angle X-ray diffraction (LAXD) and cyclic voltammetry (CV) were used to characterize the structural and compositional information of the modified surfaces. The immobilized catalyst films were tested for the Suzuki-Miyaura reaction and displayed high activity for the preparation of various biaryls at elevated temperatures in neat water without ligands. It also presented good stability and reusability. It can be reused at least 8 times with little Pd leaching into the crude product. The reasonable and feasible reaction mechanism of the heterogeneous Suzuki-Miyaura reaction based on the results of AFM, XPS, and CV tests of different reaction times were explored in detail, in which a cycle of PdII to Pd 0 and Pd0 to PdII on the surface was clearly detected and illustrated. In this approach, Pd0 on the surface of nano-sheet films as an active surface to catalyze the coupling reaction of aromatic halides and borophenylic acid proceeded via a mechanism of surface-catalyzed process.
