556-82-1Relevant articles and documents
Configurational Stability of a Cyclopropyl Grignard Reagent Containing a Metalated 2-Hydroxymethyl Group
Richey, Herman G.,Moses, L. Meredith
, p. 4013 - 4017 (1983)
Mixtures of cis- and trans-2-bromo-3-(hydroxymethyl)-1,1-dimethylcyclopropane were treated with methylmagnesium bromide to metalate the hydroxyl groups and then with magnesium to form metalated Grignard reagents.The compositions of products obtained upon hydrolysis with D2O indicated that the metalated Grignard reagents in refluxing diethyl ether did not undergo significant cis-trans isomerization.This work provides an example of the configurational stability of a cyclopropyl Grignard reagent with a secondary rather than a tertiary α-carbon.Because of these resultswith cyclopropyl Grignard reagents containing a metalated hydroxyl group, prior observations on additions of allylic Grignard reagents to 3-(hydroxymethyl)cyclopropenes only of products resulting from a cis relationship of magnesium and hydroxymethyl must be due to the stereochemistry of the addition process rather than to a subsequent isomerization.
Reaction of Methylbutenol with Hydroxyl Radical: Mechanism and Atmospheric Implications
Rudich, Yinon,Talukdar, Ranajit,Burkholder, James B.,Ravishankara, A. R.
, p. 12188 - 12194 (1995)
The tropospheric fate of 2-methyl-3-buten-2-ol (methylbutenol, MBO), a recently identified emission by vegetation, was investigated by measuring its UV absorption cross sections (210-300 nm) and the rate coefficient for its reaction with hydroxyl free radicals.UV absorption cross sections were found to be too small for photolysis to be an important removal pathway for MBO in the troposphere.The rate constant applicable under tropospheric conditions for the reaction of OH with MBO was determined to be k=(8.2 +/- 1.2) * 10-12 e((610 +/- 50)/T) cm3 molecule-1 s-1.The OH reaction proceeds mainly via addition of the OH to the double bond in MBO.In the absence of O2, about 15-20percent of the adducts eliminate the alcohol-OH group.However, O2 can scavenge the adduct before it decomposes at T 300 K.This mechanism was confirmed by measuring the rate coefficients for the reactions of OD and 18OH and determining the rate coefficient for the OH reaction in the presence of 7-13 Torr of O2 and in SF6 buffer gas.The elimination of alcohol-OH group was substantiated by observing OH production in the reactions of 18OH and OD.The obtained OH reaction rate coefficient suggests that the primary daytime loss of MBO in the troposphere is via its reaction with OH.
Cationic Ru complexes anchored on POM via non-covalent interaction towards efficient transfer hydrogenation catalysis
Chen, Manyu,Cui, Kai,Hou, Zhenshan,Peng, Qingpo,Wang, Jiajia,Wei, Xinjia,Zhao, Xiuge
, (2021/12/22)
The ionic materials consisting of cationic Ru complexes and Wells-Dawson polyoxometalate anion (POM, K6P2W18O62) have been constructed via a non-covalent interaction. The as-synthesized catalysts have been characterized thoroughly by NMR, XRD, FESEM, and FT-IR, etc. The characterization suggested that a hydrogen bond interaction occurred between the proton of the amine ligand in the cationic Ru complexes and the oxygen atom of the POM anion. The hydrogen bond played an important role in enhancing catalytic activity for the transfer hydrogenation of methyl levulinate (ML) to γ-valerolactone (GVL) under very mild conditions. Especially, the transfer hydrogenation reaction proceeded via a heterogeneous catalysis approach and the heterogenized catalysts even afforded much better catalytic performance than homogeneous analogs. Notably, the catalysts can be recycled without an obvious loss of activity, and further extended to highly selective transfer hydrogenation of α,β-unsaturated ketones and aldehydes, etc. into the corresponding α,β-unsaturated alcohols without any base external additives. The high catalytic performance of these anchored catalysts was highly related to the hydrogen bond interaction and the basicity of the polyanion. The obtained knowledge from this work could lead us to a new catalysis concept of tethering active homogeneous complexes for constructing highly active anchored Ru complex catalysts for hydrogenation reaction.
Metal oxide coated ceramic corrugated plate catalyst, preparation and application in preparation of key intermediates of citral
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Page/Page column 9, (2021/04/14)
The present disclosure belongs to the technical field of catalysis, and particularly relates to a metal oxide coated ceramic corrugated plate catalyst, its preparation method and application thereof in preparation of key intermediates of citral. The catalyst consists of a ceramic corrugated plate carrier and a metal oxide active layer coated on a surface of the carrier, wherein the metal oxide active layer is a metal oxide formed by active ingredient titanium and at least four other metal elements selected from vanadium, chromium, manganese, iron, zirconium, niobium and molybdenum.
Ir nanoclusters confined within hollow MIL-101(Fe) for selective hydrogenation of α,β-unsaturated aldehyde
Chen, Yurong,Li, Guangqin,Li, Yinle,Liu, Qian,Liu, Qinghua,Liu, Qinglin,Su, Hui
supporting information, (2021/08/13)
Although the selective hydrogenation of α,β-unsaturated aldehyde to unsaturated alcohol (UOL) is an extremely important transformation, it is still a great challenge to achieve high selectivity to UOL due to thermodynamic favoring of the C[dbnd]C hydrogenation over the C[dbnd]O hydrogenation. Herein, we report that iridium nanoclusters (Ir NCs) confined within hollow MIL-101(Fe) expresses satisfied reaction activity (93.9%) and high selectivity (96.2%) for the hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) under 1 bar H2 atmosphere and room temperature. The unique hollow structure of MIL-101(Fe) benefits for the fast transport of reactant, ensuring the comparable reaction activity and better recyclability of Ir@MIL-101(Fe) than the counterparts which Ir NCs were on the surface of MIL-101(Fe). Furthermore, The X-ray photoelectron spectroscopy data indicates the electropositive Ir NCs, owing to the electron transfer from Ir to MIL-101(Fe), can interact with oxygen lone pairs, and Fourier transform infrared spectrum shows the Lewis acid sites in MIL-101(Fe) can strongly interact with C[dbnd]O bond, which contributes to a high selectivity for COL. This work suggests the considerable potential of synergetic effect between hollow MOFs and metal nanoclusters for selective hydrogenation reactions.
Preparation method of 3-methyl-2-butenol
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Paragraph 0026-0027; 0028-0029; 0030-0031; 0032-0049, (2020/12/08)
The invention provides a preparation method of 3-methyl-2-butenol. The preparation method comprises the following steps: carrying out an isomerization reaction on 2-methyl-3-butene-2-ol in a tubular reactor under the catalysis of a ruthenium catalyst to obtain the 3-methyl-2-butenol. No solvent is added in a reaction process, 2-methyl-3-butene-2-ol is subjected to the isomerization reaction in thetubular reactor to obtain a mixture of the 3-methyl-2-butene-2-ol and the 2-methyl-3-butene-2-ol, the mixture is rectified and separated to obtain the pure 3-methyl-2-butene-2-ol, and the 3-methyl-2-butene-2-ol obtained through recovery is returned to a reaction process, and continues to participate in the reaction. The method has the advantages of simple process flow, few side reactions, high reaction selectivity and high conversion rate.
Method for preparing 3-methyl-2-butenol through photocatalysis
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Paragraph 0037-0053, (2021/01/04)
The invention discloses a method for preparing 3-methyl-2-butenol through photocatalysis. The 3-methyl-3-butenol is efficiently subjected to isomerization reaction through photocatalysis reaction to obtain the 3-methyl-2-butenol. The method solves the problem of generation of isoamyl alcohol in the traditional preparation process of 3-methyl-2-butenol, and has the advantages of mild reaction conditions, simple operation, high product yield and easy separation.
Preparation method of allylic alcohol
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Paragraph 0023-0036, (2020/02/20)
The invention belongs to the technical field of fine chemical industry. A heterogeneous catalyst technology is adopted, a complex catalyst is of a chelate structure and is formed by diphosphine ligandand transition metal compounds, the complex catalyst is used for catalyzing heterogeneous rearrangement of 3-methyl-3-butene-1-alcohol, production of by-products such as isoamyl alcohol and isopreneare inhibited at the same time, the conversion rate of raw materials is increased, and the product selectivity is improved. The invention provides a preparation method of the catalyst. The invention relates to a preparation method of allylic alcohol. Preparation is carried out by adopting a 3-methyl-3-butene-1-alcohol heterogeneous rearrangement technology. The preparation method is characterizedin that heterogeneous rearrangement is completed with the 1,3-bi(diphenylphosphine)propane-palladium-acetate chelate complex as the catalyst and on the conditions that hydrogen exists, the temperatureranges from 50 DEG C to 80 DEG C, and the time ranges from 20 minutes to 2 hours. According to the preparation method, the raw materials are easy to get, the cost is low, the repeated usage time number of catalysts is large, no three wastes are produced, and the energy consumption is low; and because of energy saving, consumption reduction and environmental protection, and the high conversion rate of the raw materials and the high product selectivity, the preparation method is suitable for preparing allylic alcohol and is especially suitable for preparing high-quality allylic alcohol.
Nickel-Catalyzed Asymmetric Reductive 1,2-Carboamination of Unactivated Alkenes
He, Jun,Xue, Yuhang,Han, Bo,Zhang, Chunzhu,Wang, You,Zhu, Shaolin
supporting information, p. 2328 - 2332 (2020/01/08)
Starting from diverse alkene-tethered aryl iodides and O-benzoyl-hydroxylamines, the enantioselective reductive cross-electrophilic 1,2-carboamination of unactivated alkenes was achieved using a chiral pyrox/nickel complex as the catalyst. This mild, modular, and practical protocol provides rapid access to a variety of β-chiral amines with an enantioenriched aryl-substituted quaternary carbon center in good yields and with excellent enantioselectivities. This process reveals a complementary regioselectivity when compared to Pd and Cu catalysis.
Engineering Catalysts for Selective Ester Hydrogenation
Dub, Pavel A.,Batrice, Rami J.,Gordon, John C.,Scott, Brian L.,Minko, Yury,Schmidt, Jurgen G.,Williams, Robert F.
, p. 415 - 442 (2020/03/04)
The development of efficient catalysts and processes for synthesizing functionalized (olefinic and/or chiral) primary alcohols and fluoral hemiacetals is currently needed. These are valuable building blocks for pharmaceuticals, agrochemicals, perfumes, and so forth. From an economic standpoint, bench-stable Takasago Int. Corp.'s Ru-PNP, more commonly known as Ru-MACHO, and Gusev's Ru-SNS complexes are arguably the most appealing molecular catalysts to access primary alcohols from esters and H2 (Waser, M. et al. Org. Proc. Res. Dev. 2018, 22, 862). This work introduces economically competitive Ru-SNP(O)z complexes (z = 0, 1), which combine key structural elements of both of these catalysts. In particular, the incorporation of SNP heteroatoms into the ligand skeleton was found to be crucial for the design of a more product-selective catalyst in the synthesis of fluoral hemiacetals under kinetically controlled conditions. Based on experimental observations and computational analysis, this paper further extends the current state-of-the-art understanding of the accelerative role of KO-t-C4H9 in ester hydrogenation. It attempts to explain why a maximum turnover is seen to occur starting at 25 mol % base, in contrast to only 10 mol % with ketones as substrates.
