590-66-9Relevant academic research and scientific papers
Reduction of α,β-unsaturated carbonyl compounds and 1,3-diketones in aqueous media, using a raney ni-al alloy
Simion, Cristian,Mitoma, Yoshiharu,Katayama, Yumi,Simion, Alina Marieta
, p. 51 - 55 (2021/02/03)
The treatment of α,β-unsaturated carbonyl compounds and 1,3-diketones with Raney Ni-Al alloy in aqueous media yielded as major reaction products the corresponding saturated alcohols and/or the corresponding hydrocarbons, in a complete transformation of the starting material.
Reduction of α,β-Unsaturated carbonyl compounds and 1,3-Diketones in aqueous media, using a raney ni-al alloy
Katayama, Yumi,Mitoma, Yoshiharu,Simion, Alina Marieta,Simion, Cristian
, p. 51 - 55 (2020/07/23)
The treatment of α,β-unsaturated carbonyl compounds and 1,3-diketones with Raney Ni-Al alloy in aqueous media yielded as major reaction products the corresponding saturated alcohols and/or the corresponding hydrocarbons, in a complete transformation of the starting material.
Photocatalytic degradation of benzothiophene by a novel photocatalyst, removal of decomposition fragments by MCM-41 sorbent
Hosseini, Asma,Faghihian, Hossein
, p. 2383 - 2401 (2019/01/29)
In this study, a catalyst was synthesized by introduction of ZnO onto the surface of FSM-16 catalyst support (ZnO/FSM-16). Impregnation of catalyst support by ZnO proceeded through reacting of FSM-16 nanoparticles with Zn(CH3COO)2 solution followed by calcination of the product. The synthesized photocatalyst was then identified by different methods, and the optical property of the photocatalyst was studied by the DRS method. The results showed that after deposition of photocatalyst on FSM-16 support, the photocatalyst band gap was shifted to the visible region. The photoluminescence studies revealed lower recombination of electron–holes of the photocatalyst after immobilization on FSM-16. The influence of different variables on the photocatalytic performance of the samples was studied. Under optimized conditions, the high degradation efficiency of 97% was obtained by ZnO/FSM-16. The compounds produced from degradation of benzothiophene were recognized by the GC–MS method, and the products containing sulfur were properly adsorbed by MCM-41 sorbent. The photocatalyst showed high regeneration capability, and its activity was mostly preserved after six regeneration cycles.
Catalytic Reduction of Alkyl and Aryl Bromides Using Propan-2-ol
Haibach, Michael C.,Stoltz, Brian M.,Grubbs, Robert H.
supporting information, p. 15123 - 15126 (2017/11/20)
Milstein's complex, (PNN)RuHCl(CO), catalyzes the efficient reduction of aryl and alkyl halides under relatively mild conditions by using propan-2-ol and a base. Sterically hindered tertiary and neopentyl substrates are reduced efficiently, as well as more functionalized aryl and alkyl bromides. The reduction process is proposed to occur by radical abstraction/hydrodehalogenation steps at ruthenium. Our research represents a safer and more sustainable alternative to typical silane, lithium aluminium hydride, and tin-based conditions for these reductions.
The reaction of biphenyl radical anion and dianion with alkyl fluorides. From ET to SN2 reaction pathways and synthetic applications
Pérez, Henoc,Melero, Cristóbal,Guijarro, Albert,Yus, Miguel
experimental part, p. 10769 - 10783 (2010/02/28)
The reaction of dilithium biphenyl (Li2C12H10) with alkyl fluorides has been studied from the point of view of the distribution of products. Two main reaction pathways, the nucleophilic substitution (SN2) and the electron transfer (ET), can compete to yield the same alkylation products in what is known as the SN2-ET dichotomy. SN2 seems to be the main mechanism operating with primary alkyl fluorides (n-RF). Alkylation proceeds in good yields, and the resulting alkylated dihydrobiphenyl anion (n-RC12H10Li) can be trapped with a second conventional electrophile (E+) affording synthetically interesting dearomatized biphenyl derivatives (n-RC12H10E). The reaction gives a higher amount of ET products as we move to secondary (s-RF) and to tertiary alkyl fluorides (t-RF), in which case the mechanism seems to be dominated by ET. In this case, alkylation by radical coupling is still feasible, giving access to the synthesis of t-RC12H10E, although in lower yields. A rational interpretation of this SN2-ET dichotomy is given on the basis of the full distribution of products observed when 5-hexenyl fluoride and 1,1-dimethyl-5-hexenyl fluoride were are used as radical probes in their reaction with Li2C12H10 and LiC12H10.
Isomerization of cycloheptane, cyclooctane, and cyclodecane catalyzed by sulfated zirconia - Comparison with open-chain alkanes
Satoh, Daishi,Matsuhashi, Hiromi,Nakamura, Hideo,Arata, Kazushi
, p. 4343 - 4349 (2007/10/03)
The skeletal isomerization of cycloalkanes with the number of carbons greater than six, cycloheptane, cyclooctane, cyclodecane, and cyclododecane, was performed over sulfated zirconia in liquid phase at 50°C. A main product of methylcyclohexane was formed from cycloheptane via a protonated cyclopropane intermediate, protonated [4.1.0]bicycloheptane, together with small amounts of trans-1,2-dimethylcyclopentane, as- and trans-1,3- dimethylcyclopentanes, 1,1-dimethylcyclopentane, and ethylcyclopentane. A major product from cyclooctane was ethylcyclohexane via a protonated cyclobutane intermediate, protonated [4.2.0]bicyclooctane, followed by cis-1,3- dimethylcyclohexane in addition to small amounts of trans-1,2-, -1,3-, -1,4-dimethylcyclohexanes, 1,1-dimethylcyclohexane, and methylcycloheptane. The detailed reaction-paths for cycloheptane and cyclooctane were shown after additional examinations in reactions of methylcyclohexane, ethylcyclopentane, ethylcyclohexane, and 1,2-dimethylcyclohexane. Cyclodecane was dehydrogenated into cis- or trans-decaline with the evolution of a dihydrogen. Cyclododecane was converted into lots of products, more than 30 species.
Rate Constants and Arrhenius Parameters for the Reactions of Some Carbon-Centered Radicals with Tris(trimethylsilyl)silane
Chatgilialoglu, C.,Dickhaut, J.,Giese, B.
, p. 6399 - 6403 (2007/10/02)
Rate constants for the reactions of some carbon-centered radicals with (Me3Si)3SiH have been measured over a range of temperatures by using competing unimolecular radical reactions as timing devices.For example, the rate constants (at 298 K) are 3.7, 1.4, and 2.6 x 1E5 M-1 s-1 from primary, secondary, and tertiary alkyl radicals, respectively.Comparison of the radical trapping abilities of tri-n-butylstannane and tris(trimethylsilyl)silane is discussed.The use of 1,1-dimethyl-5-hexenyl cyclization as a radical clock has been recalibrated by using new data and data from the literature.
Radical Cations of Cyclohexanes Alkyl-substituted on One Carbon: An ESR Study of the Jahn-Teller Distorted HOMO of Cyclohexane
Shiotani, Masaru,Lindgren, Mikael,Ohta, Nobuaki,Ichikawa, Takahisa
, p. 711 - 719 (2007/10/02)
Cation radicals of cyclohexanes alkyl-substituted on one carbon have been stabilized in perfluoromethylcyclohexane and other halocarbon matrices at 4.2 K and studied by means of ESR spectroscopy.It was found that all have an electronic ground state resembling the 2Ag state of the cyclohexane cation, one of the possible states following a Jahn-Teller distortion of the D3d cyclohexane chair structure.The cations can be classified into two groups depending on the substituted alkyl group.To the first group belong the cations with a methyl group or a primary carbon (ethyl, n-propyl or isobutyl group) attached to the ring.The disubstituted cyclohexane cations of 1,1-dimethylcyclohexane and 1-methyl-1-ethylcyclohexane were also found to have a similar structure.The ESR spectra are characterized by a 1:2:1 three-line pattern with the hyperfine (hf) splitting due to two magnetically equivalent equatorial ring hydrogens.The magnitude of the splitting was found to depend on the size and number of substituents, ranging from 74 G (methylcyclohexane.+) to 55 G (isobutylcyclohexane.+).An additional doublet, 17-34 G, due to a hydrogen on the substituent could be detected in certain cases.Such hydrogens are axial with one of the elongated C-C bonds in the ring structure which contains a relatively large fraction of the unpaired electron.It follows that the substituents are located asymmetrically with respect to an ag-like SOMO in the ring.In the second group a secondary or tertiary carbon connects the substituent to the ring, such as an isopropyl or tert-butyl group.The largest hf splittings are ca. 30 G in magnitude, due to certain hydrogens on the substituent which are axial with respect to the cyclohexyl bond.It follows that an ag-like SOMO in the ring here is symmetrically arranged with respect to the position of the substituent.Hyperconjugation is the dominating mechanism for the spin transfer in all cations reported in this study.
Mirror Inversion of the Low-symmetry Ground-state Structures of the Methylcyclohexane and 1,1-Dimethylcyclohexane Radical Cations
Sjoeqvist, Lars,Lindgren, Mikael,Lund, Anders,Shiotani, Masaru
, p. 3377 - 3382 (2007/10/02)
The dynamics of the methylcyclohexane and 1,1-dimethylcyclohexane radical cations in a solid perfluoromethylcyclohexane matrix at low temperature have been studied by electron paramagnetic resonance (EPR) spectroscopy.The reversible variations of the experimental EPR linewidth, observed for both cations in the temperature region 4-173 K, have been reproduced through simulations employing a dynamical model for the molecular motion.It was assumed that an interconversion between two energetically equivalent mirror images of the molecular framework occurred.The related activation energy has been determined to be 0.2 and 0.3 kcal mol-1 for the methylcyclohexane and 1,1-dimethylcyclohexane radical cations, respectively.
On the Mechanism of the Reduction of Primary Halides with Grignard Reagents in the Presence of (dppf)PdCl2 or (dppf)Pd(0)
Yuan, Kaixu,Scott, William J.
, p. 6188 - 6194 (2007/10/02)
Reaction of primary alkyl halides with Grignard reagents in the presence (dppf)PdCl2 or (dppf)Pd(0) leads to reduction of the halide.The mechanism of the reduction is dependent on the solvent and the Grignard reagent.In tetrahydrofuran, reduction is independent of palladium.The alkyl halide is largely reduced by β-hydride transfer from the Grignard reagent.Competing with hydride transfer is a halogen-metal exchange reaction, which converts the alkyl halide into the corresponding Grignard reagent.Protonation of reaction mixture then gives the observed products.Grignard reagents that do not possess β-hydrogens undergo the halogen-metal exchange exclusively, but still lead to reduction of the alkyl halide.At subambient temperatures and in diethyl ether, reduction of primary alkyl halides with Grignard reagents in the absence of palladium catalysts is very slow.That reduction which does occur is almost exclusively the product of β-hydride transfer.The addition of (dppf)PdCl2 markedly accelerates the rate of reduction of alkyl halides in diethyl ether.The catalytic effect is proposed to occur through a catalytic cycle involving oxidative addition of the alkyl halide, hydride-transfer, and reductive-elimination steps.The order of the first two steps remains unclear.
