501-65-5Relevant articles and documents
Preparation, characterization and catalytic properties of Pd-decorated carbon nanotubes possessing different linkers
Kim, Ja Young,Park, Kyungho,Bae, Seung Yong,Kim, Gwui Cheol,Lee, Sunwoo,Choi, Hyun Chul
, p. 5999 - 6005 (2011)
To investigate the relationship between the linker length and the catalytic activities of metal-decorated CNTs, three samples were prepared with different linker molecules, viz. NaSH, HSCH2CH2SH, and C 2H2N
Fast synthesis of Ag-Pd@reduced graphene oxide bimetallic nanoparticles and their applications as carbon-carbon coupling catalysts
Chen, Mingxi,Zhang, Zhe,Li, Lingzhi,Liu, Yu,Wang, Wei,Gao, Jianping
, p. 30914 - 30922 (2014)
Ultrafine Ag-Pd bimetallic nanoparticles homogeneously distributed on reduced graphene oxide (rGO) were prepared by redox reactions between Pd 2+, Ag+ and GO. This method is simple, and the use of rGO as a support facilitated the separation and reuse of the Ag-Pd@rGO catalyst. The Ag-Pd@rGO bimetallic nanoparticles were characterized by ultraviolet-visible spectroscopy, Raman spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The microstructure of the Ag-Pd@rGO was investigated with scanning electron microscopy and transmission electron microscopy. The Ag-Pd@rGO catalyst exhibited high catalytic activities in the Suzuki-Miyaura carbon coupling reaction and the Sonogashira carbon coupling (SCC) reaction. These reactions used mild, efficient, ligand-free and heterogeneous conditions. Interestingly, the presence or absence of oxygen in the SCC catalytic system resulted in two different products, in which oxygen can be used as "switch" to control different products. the Partner Organisations 2014.
Functionalization of complexed N2O in bis(pentamethylcyclopentadienyl) systems of zirconium and titanium
Mindiola, Daniel J.,Watson, Lori A.,Meyer, Karsten,Hillhouse, Gregory L.
, p. 2760 - 2769 (2014)
Methyl triflate reacts with the metastable azoxymetallacyclopentene complex Cp2Zr(N(O)NCPhCPh), generated in situ from nitrous oxide insertion into the Zr-C bond of Cp2Zr(η2-PhCCPh) at -78 °C, to afford the salt [Cp2Zr(N(O)N(Me)CPhCPh)][O3SCF 3] (1) in 48% isolated yield. A single-crystal X-ray structure of 1 features a planar azoxymetallacycle with methyl alkylation taking place only at the β-nitrogen position of the former Zr(N(O)NCPhCPh) scaffold. In addition to 1, the methoxy-triflato complex Cp2Zr(OMe)(O3SCF 3) (2) was also isolated from the reaction mixture in 26% yield and fully characterized, including its independent synthesis from the alkylation of Cp2Zr=O(NC5H5) with MeO3SCF 3. Complex 2 could also be observed, spectroscopically, from the thermolysis of 1 (80 °C, 2 days). In contrast to Cp2Zr(N(O) NPhCCPh), the more stable titanium N2O-inserted analogue, Cp 2Ti(N(O)NCPhCPh), reacts with MeO3SCF3 to afford a 1:1 mixture of regioisomeric salts, [Cp2Ti(N(O)N(Me)CPhCPh)] [O3SCF3] (3) and [Cp2Ti(N(OMe)NCPhCPh)][O 3SCF3] (4), in a combined 65% isolated yield. Single-crystal X-ray diffraction studies of a cocrystal of 3 and 4 show a 1:1 mixture of azoxymetallacyle salts resulting from methyl alkylation at both the β-nitrogen and the β-oxygen of the former Ti(N(O)NCPhCPh ring. As opposed to alkylation reactions, the one-electron reduction of Cp 2Ti(N(O)NCPhCPh) with KC8, followed by encapsulation with the cryptand 2,2,2-Kryptofix, resulted in the isolation of the discrete radical anion [K(2,2,2-Kryptofix)][Cp2Ti(N(O)NCPhCPh)] (5) in 68% yield. Complex 5 was studied by single-crystal X-ray diffraction, and its solution X-band EPR spectrum suggested a nonbonding σ-type wedge hybrid orbital on titanium, d(z2)/d(x2-y2), houses the unpaired electron, without perturbing the azoxymetallacycle core in Cp 2Ti(N(O)NCPhCPh). Theoretical studies of Ti and the Zr analogue are also presented and discussed.
Aromatic PCN pincer palladium complexes: forming and breaking C[sbnd]C bonds
Mousa, Abdelrazek H.,Fleckhaus, André,Kondrashov, Mikhail,Wendt, Ola F.
, p. 157 - 164 (2017)
Through a salt metathesis reaction, (t?BuPCN)Pd-ONO2 (2) was prepared and used as a precursor for producing (t?BuPCN)Pd-OH (3) and (t?BuPCN)Pd-aryl acetylide complexes 4 (phenyl acetylide) and 5 (p-tolyl acetylide). The aryl acetylide complexes could also be prepared through another synthetic route: by condensation of 3 with the corresponding aryl acetylene. The reactivity of complexes 3 and 4 toward carbon dioxide was studied and it was found that both reactions give the hydrogen carbonate complex (6). The low reactivity of the Pd-acetylide bond was further confirmed by the fact that the propiolate complex undergoes decarboxylation to give 4. PCN palladium complexes are good catalysts for the decarboxylative cross coupling reactions between acetylene carboxylic acids and aryl halides. The yield of the cross coupling product was improved by adding a catalytic amount of CuI.
A Mo(VI) Alkylidyne complex with polyhedral oligomeric silsesquioxane ligands: Homogeneous analogue of a silica-supported alkyne metathesis catalyst
Hyeon, Mo Cho,Weissman, Haim,Wilson, Scott R.,Moore, Jeffrey S.
, p. 14742 - 14743 (2006)
A highly active alkyne metathesis catalyst is realized by replacing the amide ligands of a molybdenum(VI) trisamide alkylidyne complex with silanol groups from incompletely condensed POSS (polyhedral oligomeric silsesquioxane) ligands. This catalyst serves as an effective homogeneous mimic of an amorphous silica-supported catalyst. Reactivities of various catalytic mixtures are reported along with an X-ray structure of the aniline-coordinated amidodisiloxymolybdenum(VI) alkylidyne complex. Copyright
Photoreduction of 1,1-diphenyl-2-haloethenes by metal hydrides
Zupancic, Natasa,Sket, Boris
, p. 9071 - 9082 (1991)
The nature of the photochemical carbon - halogen bond cleavage in the presence of sodium borohydride or lithium aluminium hydride as reducing agents was studied when a halogen atom is bonded to the sp2 hybridized carbon atom, which is a part of a vinyl system. Irradiation of 1,1-diphenyl-2-bromoethene, or 1,1-diphenyl-2-chloroethene, in the presence of the metal hydrides resulted in an increased formation of the photoreduced product 1,1-diphenylethene in comparison to reactions run in their absence. Conversion of the starting compound and the products distribution depended on the halogen atom bonded, the reducing agent, and the solvent used.
Synthesis and characterization of copper(I) compounds incorporating pyrazole-derived ligands: A study on carbon-carbon coupling reaction
Li, Chen-Yi,Lien, Yu-Ling,Vinayagam, Jayaramann,Datta, Amitabha,Hu, Ting-Chia,Lin, Chia-Her,Huang, Jui-Hsien
, p. 327 - 334 (2015)
A series of copper(I) compounds manifesting with the pyrazole mediated precursor, ArN[CH2(C3H3N2)]2 (Ar = 2,6-diisopropylphenyl) (LN3), were synthesized conveniently and treatment of the derivatives with small organic molecules like pyrazine and triphenylphosphine were analyzed. Reacting one and two equivalents of LN3 with [Cu(CH3CN)4]PF6 in CH3CN at room temperature afforded [Cu(LN3)(CH3CN)2]PF6 (1) and [Cu(LN3)2]PF6 (2), respectively in high yield. Similarly, while reacting one equivalent of LN3 and CuI in acetonitrile for 12 h, produced a white solid, [Cu(LN3)]I (3). Furthermore, by adding one or two equivalents of PPh3 into compound 1, using methylene chloride as solvent rendered [Cu(LN3)(PPh3)]PF6 (4) and [Cu(LN3)(PPh3)2]PF6 (5), respectively, in satisfactory yield. In addition, compound {[Cu(LN3)(C4H4N2)]2(PF6)2}n (6) was generated as one-dimensional polymer by treating compound 1 and pyrazine in THF at room temperature. All the Cu(I)-derivatives were characterized by 1H and 13C NMR spectroscopy and the molecular structures (1, 4, and 6) were determined by single crystal X-ray diffraction. Additionally, the catalytic reactions of Sonogashira type C-C coupling were discussed using compounds 2, 3, 5, and 6 as catalysts.
Selective synthesis of Cu2O nanocrystals as shape-dependent catalysts for oxidative arylation of phenylacetylene
Li, Lingling,Nan, Caiyun,Peng, Qing,Li, Yadong
, p. 10491 - 10496 (2012)
Shape-dependent nanocatalysis: Monodisperse cubic, rhombic dodecahedral, and octadecahedral Cu2O nanocrystals (NCs) were selectively synthesized. Cu2O octadecahedra exhibited the best activity upon recycling, though etched on nanoframes, in the ligand-free oxidative arylation of phenylacetylene. Rhombic dodecahedra had moderate activity and optimal stability, whereas cubes suffered significant loss of activity during recycling. Copyright
EFFICIENT COPPER-CATALYZED OXIDATION OF DIHYDRAZONES OF α-DIKETONES TO DISUBSTITUTED ACETYLENES
Tsuji, Jiro,Kezuka, Hiroaki,Toshida, Yomishi,Takayanagi, Hiroshi,Yamamoto, Keiji
, p. 3279 - 3282 (1983)
Dihydrazones of α-diketones were oxidized by using Cu2Cl2/O2/pyridine system in dichloromethane at room temp to give disubstituted acetylenes.Although the dihydrazones were found to be oxidized with four equivalents of Cu(II) salt without oxygen, efficien
Intermolecular σ-Bond Cross-Exchange Reaction between Cyclopropenones and (Benzo)silacyclobutanes: Straightforward Access towards Sila(benzo)cycloheptenones
Zhao, Wen-Tao,Gao, Fang,Zhao, Dongbing
, p. 6329 - 6332 (2018)
Described herein is the first intermolecular σ-bond exchange reaction between the C?C bond of cyclopropenones and C?Si bond of (benzo)silacyclobutanes and it proceeds smoothly by treatment with either 1 mol % of a palladium or 2 mol % of a nickel catalyst. This reaction constitutes an unprecedented route for the synthesis of various sila(benzo)suberones. And it is also the first example of a σ-bond exchange reaction involving cyclopropenones.
