124-18-5Relevant articles and documents
Nickelocene-Lithium Aluminium Hydride, A New Effective Desulphurization Reagent
Chan, Man-Chor,Cheng, Kwok-Man,Li, Man Kong,Luh, Tien-Yau
, p. 1610 - 1611 (1985)
The carbon-sulphur bonds in thiols, sulphides, and thioacetals are reductively cleaved by nickelocene-lithium aluminium hydride.
REACTIONS OF ATOMIC MAGNESIUM IN THE BASIC STATE WITH ORGANIC CHLORINE DERIVATIVES AT LOW TEMPERATURES
Sergeev, G. B.,Smirnov, V. V.,Zagorsky, V. V.
, p. 9 - 20 (1980)
Low-temperature solid-phase reactions of atomic magnesium in the basic state with a number of aliphatic monochlorine derivatives, chlorobenzene, carbon tetrachloride and 1,2-dichloroethane, have been investigated.The nature of the intermediate particles is discussed, the effect of the phase state of a frozen hydrocarbon on its reactivity examined, and the mechanisms of reactions with the participation of radicals and ion radicals proposed.
Catalytic Hydrogenation of Alkenes Using Zirconocene-Alkene Complexes
Takahashi, Tamotsu,Suzuki, Noriyuki,Kageyama, Motohiro,Nitto, Yu,Saburi, Masahiko,Negishi, Ei-ichi
, p. 1579 - 1582 (1991)
Hydrogenation reactions of alkenes were catalyzed by zirconium-alkene complex derivatives which were prepared from Cp2ZrCl2 (Cp = η5-C5H5) and n equiv. of RR'CHCH2M (M = MgX or Li).By the use of three or more equiv. of EtMgBr relative to Cp2ZrCl2, the product yield of hydrogenation of 1-decene was remarkably improved most likely due to the stabilization of the Zr(II) species.
Tripyrrolidinophosphoric acid triamide as an activator in samarium diiodide reductions
McDonald, Chriss E.,Ramsey, Jeremy D.,Sampsell, David G.,Butler, Julie A.,Cecchini, Michael R.
, p. 5178 - 5181 (2010)
The electrochemical and spectrophotometric characterization of the complex formed from samarium diiodide and 4 equiv of tripyrrolidinophosphoric acid triamide (TPPA) is presented. Kinetic studies indicate that the SmI 2/TPPA complex possesses reactivity greater than the complex formed between samarium diiodide and 4 equiv of HMPA. Examples of the use of SmI 2/TPPA in synthesis are presented.
Direct Iodination of Alkanes
Montoro, Raul,Wirth, Thomas
, p. 4729 - 4731 (2003)
(Matrix presented) A cheap and efficient iodination of hydrocarbons can be achieved by generating tert-butyl hypoiodite from iodine and sodium tert-butoxide. The alkane is reactant and solvent, and this metal-free process provides a clean solution for their direct iodination.
Mechanistic studies of ethylene and α-olefin co-oligomerization catalyzed by chromium-PNP complexes
Do, Loi H.,Labinger, Jay A.,Bercaw, John E.
, p. 5143 - 5149 (2012)
To explore the possibility of producing a narrow distribution of mid- to long-chain hydrocarbons from ethylene as a chemical feedstock, co-oligomerization of ethylene and linear α-olefins (LAOs) was investigated, using a previously reported chromium complex, [CrCl 3(PNPOMe)] (1, where PNPOMe = N,N-bis(bis(o-methoxyphenyl)phosphino)methylamine). Activation of 1 by treatment with modified methylaluminoxane (MMAO) in the presence of ethylene and 1-hexene afforded mostly C6 and C10 alkene products. The identities of the C10 isomers, assigned by detailed gas chromatographic and mass spectrometric analyses, strongly support a mechanism that involves five- and seven-membered metallacyclic intermediates comprised of ethylene and LAO units. Using 1-heptene as a mechanistic probe, it was established that 1-hexene formation from ethylene is competitive with formation of ethylene/LAO cotrimers and that cotrimers derived from one ethylene and two LAO molecules are also generated. Complex 1/MMAO is also capable of converting 1-hexene to C12 dimers and C18 trimers, albeit with poor efficiency. The mechanistic implications of these studies are discussed and compared to previous reports of olefin cotrimerization.
Bioinspired Hollow Nanoreactor: Catalysts that Carry Gaseous Hydrogen for Enhanced Gas-Liquid-Solid Three-Phase Hydrogenation Reactions
Li, Zhaohua,Zhu, Zhongpeng,Cao, Changyan,Jiang, Lei,Song, Weiguo
, p. 459 - 462 (2020)
For conventional gas-liquid-solid three-phase heterogeneous hydrogenation reactions, hydrogen must be dissolved into the solvent to be a participating reactant, restricting the reaction rates. In this study, we demonstrate that gaseous hydrogen could be directly involved in gas-liquid-solid hydrogenation reactions through a bioinspired hollow nanoreactor with superaerophilic surface to enhance the reaction rates. We produce Pd@meso-SiO2 hollow nanoreactor, whose external surface is modified with perfluorodecyltriethoxysilane (PFDTS). In aqueous solutions, H2 gas could be spread quickly on the surface and stored in the cavity of hollow spheres, and participated in hydrogenation reactions, thereby enhancing H2 concentration around Pd nanoparticles. In hydrogenation of olefin reactions, such three-phase interface allows rapid and direct transportation of H2 bubbles to the surface of Pd nanoparticles rather than through diffusion of dissolved H2 in liquid phase, leading to an enhanced catalytic rate. This strategy is expected to be useful for designing and developing new catalytic systems of gas-liquid-solid three-phase reaction.
Supported ionic liquid phase rhodium nanoparticle hydrogenation catalysts
Gelesky, Marcos A.,Chiaro, Sandra S. X.,Pavan, Flavio A.,Dos Santos, Joao H. Z.,Dupont, Jairton
, p. 5549 - 5553 (2007)
Rh(0) nanoparticles (ca. 4 nm) dispersed in an ionic liquid (1-n-butyl-3-methylimidazolium tetrafluoroborate) were immobilized within a silica network, prepared by the sol-gel method. The effect of the sol-gel catalyst (acid or base) on the encapsulated ionic liquid and Rh(0) content, on the silica morphology and texture, and on the catalyst alkene hydrogenation activity was investigated. The Rh(0) content in the resulting xerogels (ca. 0.1 wt% Rh/SiO2) was shown to be independent of the sol-gel process. However, acidic conditions afforded higher contents of encapsulated ionic liquid and xerogels with larger pore diameters, which in turn might be responsible for the higher catalyst activity in hydrogenation of the alkenes. The Royal Society of Chemistry.
Platinum nanoparticles on carbon nanomaterials with graphene structure as hydrogenation catalysts
Kushch,Kujunko,Tarasov
, p. 706 - 710 (2009)
Carbon nanomaterials with graphene structure (single- and multiwall nanotubes and nanofibers) after oxidizing by a mixture of sulfuric and nitric acids and presumable introducing of carboxyl groups can be used as carrying agents of hydrogenation catalysts. Platinum in a concentration which should not exceed 10 wt % can be fixed using H2PtCl6 as a precursor in presence of an organic base. Catalysts based on these nanomaterials with the average size of platinum particles 6-8 nm exceed in activity the Pt/C catalyst with the size of platinum particles 65-70 nm, but are inferior to catalysts based on fullerene black with the average size of platinum particles 3-4 nm.
Tamura,Kochi
, p. 205,211 (1972)
Direct synthesis of hydrogen peroxide over Pd/C catalyst prepared by selective adsorption deposition method
Lee, Seungsun,Jeong, Hwiram,Chung, Young-Min
, p. 125 - 137 (2018)
A new catalyst design based on selective adsorption deposition method was developed to achieve high reaction performance in the direct synthesis of hydrogen peroxide. The activity of the unprecedented Pd/C catalyst was superior to that of the conventionally prepared Pd/C catalysts, and the initial H2O2 productivity and H2 selectivity reached as high as 8606 mmol H2O2/g Pd.h and 95.1%, respectively. This excellent activity may result from the intrinsic structural and electronic features of the active sites, i.e., the extremely small and monodispersed Pd nanoparticles with a high Pd2+/Pd0 ratio, which were realized by combining the selective adsorption of metal precursor cations on a negatively charged activated carbon surface and the subsequent homogeneous surface deposition of palladium hydroxide by the hydroxide ions that are slowly generated upon urea decomposition. The catalytic activity was significantly affected by the oxygen groups of the activated carbon support. The carboxyl groups do not efficiently suppress the unfavorable H-OOH dissociation but rather accelerate the H2O2 hydrolysis by forming hydrogen bonds with H2O2. Moreover, a sharp decrease in the reaction rates of H2O2 hydrogenation and direct synthesis of H2O2 was observed with the increase in the number of carboxyl groups on the activated carbon surface. This loss of activity, as confirmed by acid treatment and olefin hydrogenation experiments, implies that the carboxyl groups in close proximity to the active sites have a detrimental effect by hindering or poisoning the active sites.
Characterization of the complex formed between samarium diiodide and the dehydro dimer of HMPA (diHMPA)
McDonald, Chriss E.,Ramsey, Jeremy D.,Grant, James A.,Howerter, Kelly A.
, p. 5308 - 5310 (2009)
A new ligand that facilitates samarium diiodide-mediated reductions has been developed. Addition of a solution of samarium diiodide to the dehydro dimer of hexamethylphosphoramide results in a purple complex which is an excellent reductant for a variety of organic functionalities. The complex was characterized by the kinetics of reduction of 1-bromodecane, visible spectroscopy, and cyclic voltammetry.
Platinum nanoparticles supported on ionic liquid-modified-silica gel: Hydrogenation catalysts
Foppa, Lucas,Dupont, Jairton,Scheeren, Carla W.
, p. 16583 - 16588 (2014)
Platinum nanoparticles (ca. 2.3 nm) dispersed in ionic liquids and functionalized ionic liquids were supported within a silica network by the sol-gel method. The effect of the sol-gel catalyst (acid or base) on the encapsulated ionic liquid and on the platinum content was studied, and the silica morphology, the texture of the support material, and the hydrogenation activity were investigated. The Pt(0) content in the resulting xerogels (ca. 0.2 wt% Pt/SiO2) was shown to be independent of the sol-gel process. The acidic conditions resulted in xerogels with larger pore diameters, which in turn might be responsible for the higher catalytic activity in hydrogenation of the alkenes and arenes obtained with the heterogeneous catalyst (Pt(0)/SiO 2).
Mechanistic study of the SmI2/H2O/amine-mediated reduction of alkyl halides: Amine base strength (pKBH+) dependent rate
Dahlen, Anders,Hilmersson, Goeran
, p. 8340 - 8347 (2005)
The kinetics of the SmI2/H2O/amine-mediated reduction of 1-chlorodecane has been studied in detail. The rate of reaction is first order in amine and 1-chlorodecane, second order in SmI2, and zero order in H2O. Initial rate studies of more than 20 different amines show a correlation between the base strength (pKBH+) of the amine and the logarithm of the observed initial rate, in agreement with Bronsted catalysis rate law. To obtain the activation parameters, the rate constant for the reduction was determined at different temperatures (0 to +40 °C, ΔH? = 32.4 ± 0.8 KJ mol-1, ΔS? = -148 ± 1 J K-1 mol-1, and ΔG? 298K = 76.4 ± 1.2 kJ mol-1). Additionally, the 13C kinetic isotope effects (KIE) were determined for the reduction of 1-iododecane and 1-bromodecane. Primary 13C KIEs (k 12/k13, 20 °C) of 1.037 ± 0.007 and 1.062 ± 0.015, respectively, were determined for these reductions. This shows that cleavage of the carbon-halide bond occurs in the rate-determining step. A mechanism of the SmI2/H2O/amine-mediated reduction of alkyl halides is proposed on the basis of these results.
A metal-organic framework immobilised iridium pincer complex
Rimoldi, Martino,Nakamura, Akitake,Vermeulen, Nicolaas A.,Henkelis, James J.,Blackburn, Anthea K.,Hupp, Joseph T.,Stoddart, J. Fraser,Farha, Omar K.
, p. 4980 - 4984 (2016)
An iridium pincer complex has been immobilised in the metal-organic framework NU-1000 using a technique called solvent assisted ligand-incorporation (SALI). The framework proved to be stable under the conditions required to activate the iridium complex and spectroscopic investigations showed formation of the catalytically active iridium dihydride. The Ir-pincer modified NU-1000 is an active catalyst for the condensed phase hydrogenation of a liquid alkene (1-decene and styrene) and shows enhanced activity with respect to a homogeneous analogue. Additionally, the Ir-pincer immobilised inside NU-1000 operated as an efficient heterogenous catalyst under flow conditions.
A New Route to an Active Form of Nickel. Transfer Hydrogenation of Alkenes and Carbonyl Compounds with 2-Propanol
Boldrini, Gian Paolo,Savoia, Diego,Tagliavini, Emilio,Trombini, Claudio,Umani-Ronchi, Achille
, p. 3082 - 3086 (1985)
A new procedure for the transfer hydrogenation of alkenes and carbonyl compounds have been developed using an activated form of metallic nickel prepared by the thermal decomposition of nickel diisopropoxide in boiling 2-propanol.Monosubstituted alkenes undergo carbon-carbon double-bond migration more quickly than reduction; the 2-alkene produced is then reduced to alkane.Ketones are reduced in high yields, provided that acetone formed during the process is removed continuously.Unsaturated ketones are first converted to saturated ketones andthen to alcohols, so by a careful control of the reaction course it is possible to stop the reaction at the first stage.Finally a comparison with the transfer hydrogenation of ketones, catalyzed by alkali metal isopropoxides in 2-propanol, has been performed.
Controlling the Lewis Acidity and Polymerizing Effectively Prevent Frustrated Lewis Pairs from Deactivation in the Hydrogenation of Terminal Alkynes
Geng, Jiao,Hu, Xingbang,Liu, Qiang,Wu, Youting,Yang, Liu,Yao, Chenfei
, p. 3685 - 3690 (2021/05/31)
Two strategies were reported to prevent the deactivation of Frustrated Lewis pairs (FLPs) in the hydrogenation of terminal alkynes: reducing the Lewis acidity and polymerizing the Lewis acid. A polymeric Lewis acid (P-BPh3) with high stability was designed and synthesized. Excellent conversion (up to 99%) and selectivity can be achieved in the hydrogenation of terminal alkynes catalyzed by P-BPh3. This catalytic system works quite well for different substrates. In addition, the P-BPh3 can be easily recycled.
Ambient Hydrogenation and Deuteration of Alkenes Using a Nanostructured Ni-Core–Shell Catalyst
Beller, Matthias,Feng, Lu,Gao, Jie,Jackstell, Ralf,Jagadeesh, Rajenahally V.,Liu, Yuefeng,Ma, Rui
supporting information, p. 18591 - 18598 (2021/06/28)
A general protocol for the selective hydrogenation and deuteration of a variety of alkenes is presented. Key to success for these reactions is the use of a specific nickel-graphitic shell-based core–shell-structured catalyst, which is conveniently prepared by impregnation and subsequent calcination of nickel nitrate on carbon at 450 °C under argon. Applying this nanostructured catalyst, both terminal and internal alkenes, which are of industrial and commercial importance, were selectively hydrogenated and deuterated at ambient conditions (room temperature, using 1 bar hydrogen or 1 bar deuterium), giving access to the corresponding alkanes and deuterium-labeled alkanes in good to excellent yields. The synthetic utility and practicability of this Ni-based hydrogenation protocol is demonstrated by gram-scale reactions as well as efficient catalyst recycling experiments.
