F:Flammable;
110-83-8Relevant articles and documents
Monolithic materials: New high-performance supports for permanently immobilized metathesis catalysts
Mayr, Monika,Mayr, Betina,Buchmeiser, Michael R.
, p. 3839 - 3842 (2001)
Back to the roots: Ring-opening metathesis polymerization allows the synthesis of monolithic materials, which may be subject to an in situ derivatization with dihydroimidazolium salts through metathesis graft polymerization. This method offers an attracti
The role of la in improving the selectivity to cyclohexene of Ru catalyst for hydrogenation of benzene
Sun, Hai-Jie,Dong, Ying-Ying,Li, Shuai-Hui,Jiang, Hou-Bing,Zhang, Yuanxin,Liu, Zhong-Yi,Liu, Shou-Chang
, p. 119 - 124 (2013)
Ru-La catalysts with different La/Ru molar ratios were prepared by co-precipitation. Characterizations revealed that the promoter La existed as La(OH)3 on the Ru surface. The La(OH)3 itself could not enhance the selectivity to cyclohexene of Ru catalyst. However, the La(OH) 3 could react with ZnSO4 in slurry to form an insoluble (Zn(OH)2)3(ZnSO4)(H2O)3 salt. The chemisorbed (Zn(OH)2)3(ZnSO4)(H 2O)3 salt on Ru surface played a key role in improving the selectivity to cyclohexene of Ru catalyst. Ru-La catalyst with the optimum La/Ru molar ratio of 0.14 gave a maximum cyclohexene yield of 59.5%. Besides, Ru-La(0.14) catalyst had a good reusability and an excellent stability.
DIRECT PHOTOLYSIS AT 185 nm OF SIMPLE CYCLOBUTENES. MOLECULAR ELIMINATION OF ACETYLENE
Inoue, Yoshihisa,Sakae, Mitsuhiro,Hakushi, Tadao
, p. 1495 - 1498 (1983)
Direct photolyses at 185 nm of bicyclohept-6-ene and bicyclooct-7-ene in pentane afforded acetylene and the fragment cycloalkenes as the major photoproducts, whereas the Woodward-Hoffmann allowed ring-opening giving rise to 1,3-diene was a minor process.
Molybdenum Imido Alkylidene N-Heterocyclic Carbene Complexes: Structure–Productivity Correlations and Mechanistic Insights
Buchmeiser, Michael R.,Sen, Suman,Lienert, Christina,Widmann, Laura,Schowner, Roman,Herz, Katharina,Hauser, Philipp,Frey, Wolfgang,Wang, Dongren
, p. 2710 - 2723 (2016)
The syntheses and single-crystal X-ray structures of a series of Mo–imido alkylidene N-heterocyclic carbene (NHC) complexes (1–15) and of the first complexes containing bidentate NHC-phenolate ligands (16–18) are reported. Mo(N-2,6-Me2-C6H3)((1-R-phenethyl)-3-mesitylimidazolidin-2-ylidene)(CHR)(OTf)2 (R=CMe2Ph, 1) is the first enantiomerically pure Mo–imido alkylidene NHC catalyst. With [Mo(N-2,6-Me2-C6H3)(IMes)(CHR)(CH3CN)(OTf)(CH3CN)+ B(ArF)4?] (7), turnover numbers up to 545 000 were achieved in the homometathesis (HM) of 1-octene and 1-nonene (≤95 percent E). With 7 and 1-nonene, a turnover frequency (TOF4 min) of 8860 min?1 was determined. Productivity and E/Z-selectivity were correlated with catalyst structure. For 1, Mo(N-3,5-Me2-C6H3)(IMesH2)(CHR)(OTf)2 (9) and Mo(N-3,5-Me2-C6H3)(IMes)(CHR)(OTf)2 (10), productivity was correlated with the coalescence temperature of the two triflates, determined by variable-temperature 19F NMR spectroscopy. The square-planar conformer is postulated to be the most relevant for the catalyst activation.
Carbon support treatment effect on Ru/C catalyst performance for benzene partial hydrogenation
Zanutelo, Cristiane,Landers, Richard,Carvalho, Wagner Alves,Cobo, Antonio José Gomez
, p. 174 - 180 (2011)
Ru/C catalysts were prepared from commercial activated carbon submitted to different treatments. The catalysts were prepared by incipient wetness impregnation, through an aqueous solution of the precursor RuCl 3·xH2O. After impregnation, some catalysts were submitted to direct reduction treatment under H2 flow at the temperature of 150 °C, in order to evaluate the effects of activation. The supports were characterized by N2 adsorption, Boehm and potentiometric titration. The X-ray photoelectron spectroscopy was used to study the supports and catalysts surfaces, while scanning electron microscopy allowed us to determine the chemical composition and observe the catalysts morphology. Ru/C catalysts performance was evaluated within the hydrogenation reaction of benzene in liquid phase, using a Parr reactor. The reaction was conducted under total pressure of 5.0 MPa of H2, at a temperature of 100 °C with water in the reaction medium. The obtained results indicate that the Ru/C system catalytic performance is influenced for determined functional groups present on the activated carbon surface. The carbonyl groups decrease the activity and selectivity of the reactions, while an increase of the carboxylic groups leads to more active catalysts and the highest yield of cyclohexene.
The diagnostic substrate bicyclohexane reveals a radical mechanism for bacterial cytochrome P450 in whole cells
Austin, Rachel N.,Deng, Dayi,Jiang, Yongying,Luddy, Kate,Van Beilen, Jan B.,Ortiz De Montellano, Paul R.,Groves, John T.
, p. 8192 - 8194 (2006)
(Figure Presented) On home ground: The reaction mechanisms of bacterial alkane-oxidizing cytochrome P450s were determined in their native environment using a novel diagnostic substrate probe, bicyclohexane, in whole cells and cell-free extracts (see picture). Purified P450cam also oxidizes bicyclohexane. Clear evidence for a substrate-based radical with a lifetime of 75-250 ps was obtained.
Infrared Study of Cyclohexanol Chemisorption in SAPO Molecular Sieves
Bezouhanova, Cvetana,Kalvachev, Yuri,Lechert, Hans
, p. 3315 - 3318 (1991)
The infrared spectra of cyclohexanol adsorbed on SAPO molecular sieves (four SAPO-5 samples with different SiO2 contents, SAPO-11 and SAPO-31 were studied) show bands due to cyclohexanone (1732 cm-1) at room temperature, while on heating cyclohexene is formed.The results are discussed in terms of the existence of basic sites parallel to the Bronsted acid sites.
The Nature of the Preferred Chain-carrying Metallacarbene Intermediate in Metathesis Reactions Involving Alk-1-enes
Bencze, Lajos,Ivin, Kenneth J.,Rooney, John J.
, p. 834 - 835 (1980)
The minor products from the cross-metathesis of norbornadiene (NBD) with hex-1-ene and of cyclopentene (CP) with octa-1,7-diene (1,7-OD), respectively, show that the complexed alkylidenes, RCH= (where denotes the metal site with the ligands attached), are much preferred to the complexed methylene, CH2=, as chain carriers formed by the reactions of the terminal olefins; but CH2=, when formed, is highly reactive towards the latter, with the strongly electrophilic methylene ligand selectively adding to the terminal olefins at the C-1 position.
IrCl2H(Pi-Pr3)2 as catalyst precursor for the reduction of unsaturated substrates
Werner, Helmut,Schulz, Michael,Esteruelas, Miguel A.,Oro, Luis A.
, p. 261 - 265 (1993)
The complex IrCl2H(Pi-Pr3)2 in the presence of NaBH4 catalyzes hydrogen transfer from 2-propanol to cyclohexanone, 3-methylcyclohexanone, benzylideneacetone, styrene, and cyclohexadienes.Under the reaction conditions, the compound IrH5(Pi-Pr3)2, is formed and is the actual catalyst precursor.The complex IrCl2H(Pi-Pr3)2 reacts with hydrogen to give the dihydrido complex IrClH2(Pi-Pr3)2.In the presence of unsaturated substrates such as benzylideneacetone, phenylacetylene, styrene, and 1,4-cyclohexadiene, this reaction is inhibited, and reduction of these substrates takes place.The compound IrClH2(Pi-Pr3)2 is itself also an active catalyst for the hydrogenation of the above-mentioned substrates.
The syntheses of carbamates from reactions of primary and secondary aliphatic amines with dimethyl carbonate in ionic liquids
Sima, Tianlong,Guo, Shu,Shi, Feng,Deng, Youquan
, p. 8145 - 8147 (2002)
At 170°C and using ionic liquids as solvent and catalyst, primary and secondary aliphatic amines could react with dimethyl carbonate to give alkyl carbamates with good yield. Due to its insolubility, the desired carbamate solid could be recovered by simpl
