4192-77-2Relevant articles and documents
Heterogenization of (η5-C5Me5) Ru(PPh3)2Cl and its catalytic application for cyclopropanation of styrene using ethyl diazoacetate
Sakthivel, Ayyamperumal,Pedro, Filipe E.,Chiang, Anthony S. T.,Kuehn, Fritz E.
, p. 1682 - 1688 (2006)
(η5-C5Me5)Ru(PPh3) 2Cl (1) is heterogenized on the surface of mesoporous molecular sieves by direct grafting on mesoporous aluminosilicates or by reaction of an aminosilane-linker-modified silicate surface with the chloride ligand. Elemental analyses reveal that the grafted samples contain 0.2-1.8 wt% Ru. The retaining of long-range ordering of mesoporous MCM-41 and MCM-48 after grafting is evidenced from XRD, N2 adsorption-desorption and TEM analysis. FT-IR, TG-MS, 29Si and 1H CP MAS-NMR spectra confirm the successful grafting of complex 1 on the surface of these mesoporous materials. Mesoporous materials grafted with complex 1 are found to be promising catalysts for the cyclopropanation of styrene with ethyl diazoacetate. Georg Thieme Verlag Stuttgart.
Practical preparation method of polymer-incarcerated (PI) palladium catalysts using Pd(II) salts
Hagio, Hiroyuki,Sugiura, Masaharu,Kobayashi, Shu
, p. 375 - 378 (2006)
Polymer-incarcerated (PI) palladium catalyst was practically prepared from inexpensive Pd(II) salts and a polystyrene-based copolymer under reducing conditions. Remarkable effects of alkali metal salts on the palladium loading were observed. PI Pd thus prepared showed high catalytic activity in Mizoroki-Heck reactions and Suzuki-Miyaura couplings with a range of substrates including an aryl chloride. In all cases, the Pd catalyst was recovered quantitatively without leaching, and reused several times without significant loss of activity.
Improved cross-metathesis of acrylate esters catalyzed by 2nd generation ruthenium carbene complexes
Forman, Grant S.,Tooze, Robert P.
, p. 5863 - 5866 (2005)
The performance of cross-metathesis reactions between acrylate esters and olefins catalyzed by Grubbs catalysts have been enhanced by the simple addition of p-cresol. For example, the efficiency of the cross metathesis reaction between methyl acrylate and
Photoinduced electron transfer reactions of cyclopropanone acetal with conjugated enones in the presence of a redox-type photosensitizer
Abe, Manabu,Nojima, Masatomo,Oku, Akira
, p. 1833 - 1836 (1996)
Photoreactions of the cyclopropanone acetal 1 with conjugated enones 2 in the presence of phenanthrene or pyrene as a redox-type photosensitizer gave the corresponding cross-coupling product 3 or mixtures of 3 with 5 in good yields together with the β-carbonyl radical-dimer 4.
Zinc reduction of alkynes
Kaufman, Don,Johnson, Erin,Mosher, Michael D.
, p. 5613 - 5615 (2005)
The dissolving zinc metal reduction of ethyl phenylpropiolate to the corresponding cinnamate ester can be stereochemically controlled by changing the proton source in the reaction. The results of this study, while not fully understood, may imply that surf
Hexacoordinate phosphonium salts incorporating two (8-dimethylamino)-1-naphthyl ligands. Structure and reactivity
Carre,Chauhan,Chuit,Corriu,Reye
, p. 181 - 195 (1997)
New hexacoordinate phosphonium salts Ar2RZP+ X-[Ar = (8-dimethylamino)-1-naphthyl] with two N→P intramolecular coordinations are described. NMR studies of these salts and the X-ray structure of one of them. 5 (R = Ph, Z = H, X = Br) show that they have a dissymmetric structure with the two Me2N groups coordinated at the phosphorus centre. Salts 4 (R = Ph or Me, Z = CH2CO2Et) react slowly with PhCHO under Wittig conditions probably because of the steric hindrance around the phosphorus atom. This is confirmed by the higher reactivity of the less hindered pentacoordinate phosphonium salts ArR2P+CH2CO2Et X- 11 (R = Ph or Me) which are also much more reactive than Ph3P+CH2CO2Et Br-. This study points out the increase of reactivity of these salts due to the N→P interaction.
Palladium supported on graphene-like carbon: Preparation and catalytic properties
Kryukov, Alexander Yu.,Davydov, Sergey Yu.,Izvol'Skii, Igor M.,Rakov, Eduard G.,Abramova, Natalya V.,Sokolov, Viacheslav I.
, p. 237 - 238 (2012)
Graphene-like carbon, graphene shells, has been treated with Pd 2(dba)3 to afford the supported palladium/carbon material that provided moderate catalytic activity in the Suzuki and Heck reactions.
Triphasic liquid systems: Generation and segregation of catalytically active Pd nanoparticles in an ammonium-based catalyst-philic phase
Perosa, Alvise,Tundo, Pietro,Selva, Maurizio,Canton, Patrizia
, p. 4480 - 4482 (2006)
A triphasic liquid system fabricated from isooctane, aqueous base, and trioctylmethylammonium chloride/decanol promoted the formation of Pd-nanoparticles in the size range of 2-4 nm which remained immobilised in the onium phase, catalysed organic reactions, and could be recycled. The Royal Society of Chemistry 2006.
Synthesis of α-diazoesters from α-hydrazonoesters: Utilization of α-hydrazonoesters and α-diazoesters for convenient interconversion
Yasui, Eiko,Ishimine, Kanako,Nitanai, Sohta,Hatakeyama, Nanami,Nagumo, Shinji
, (2022/04/07)
We have developed a novel method to synthesize α-diazoesters from α-hydrazonoesters with a catalytic amount of Cu(OAc)2 in acetonitrile. When the reaction was carried out under an argon atmosphere, the reaction stopped halfway, suggesting that this reaction required oxygen to reoxidize the catalyst. Since hydrazonoesters can be obtained by reduction of α-diazoesters with P(n-Bu)3 in diisopropyl ether, these 2 compounds are mutually interconvertible with ease. Whereas α-diazoesters are unstable and unsuitable for storage, hydrazonoesters are more stable, especially crystalline hydrazonoesters. Thus, hydrazonoesters, which are suitable for long-term storage, could be conveniently used as precursors for α-diazoesters.
Pd supported on clicked cellulose-modified magnetite-graphene oxide nanocomposite for C-C coupling reactions in deep eutectic solvent
Karimi, Sabah,Masteri-Farahani, Majid,Niakan, Mahsa,Shekaari, Hemayat
, (2020/10/02)
Cellulose-modified magnetite-graphene oxide nanocomposite was prepared via click reaction and utilized for immobilization of palladium (Pd) nanoparticles without using additional reducing agent. The abundant OH groups of cellulose provided the uniform dispersion and high stability of Pd nanoparticles, while magnetite-graphene oxide as a supporting material offered high specific surface area and easy magnetic separation. The as-prepared nanocomposite served as a heterogeneous catalyst for the Heck and Sonogashira coupling reactions in various hydrophilic and hydrophobic deep eutectic solvents (DESs) as sustainable and environmentally benign reaction media. Among the fifteen DESs evaluated for coupling reactions, the hydrophilic DES composed of dimethyl ammonium chloride and glycerol exhibited the best results. Due to the low miscibility of catalyst and DES in organic solvents, the separated aqueous phase containing both of the catalyst and DES can be readily recovered by evaporating water and retrieved eight times with negligible loss of catalytic performance.
