88494-86-4Relevant academic research and scientific papers
Dysprosium-doped zinc tungstate nanospheres as highly efficient heterogeneous catalysts in green oxidation of terpenic alcohols with hydrogen peroxide
Batalha, Daniel Carreira,Mesquita Borges, Kellen Cristina,de Fátima Gon?alves, Rosana,de Matos Rodrigues, Murillo Henrique,Godinho, Mário Júnior,Fajardo, Humberto Vieira,de Oliveira Bruziquesi, Carlos Giovani,da Silva, Márcio José
, p. 6661 - 6670 (2021/04/22)
A green route to oxidize terpenic alcohols (nerol and geraniol) with H2O2over a solid catalyst was developed. The Dy-doped ZnWO4catalyst was synthesized by coprecipitation and microwave-assisted hydrothermal heating, containing different dysprosium loads. All the catalysts were characterized through infrared spectroscopy, powder X-ray diffraction, surface area and porosimetry, transmission electronic microscopy image, andn-butylamine potentiometric titration analyses. The influence of main reaction parameters such as temperature, the stoichiometry of reactants, loads, and catalyst nature was assessed. ZnWO42.0 mol% Dy was the most active catalyst achieving the highest conversion (98%) and epoxide selectivity (78%) in nerol oxidation. The reaction scope was extended to other terpenic alcohols (i.e., geraniol, borneol, and α-terpineol). The highest activity of ZnWO42.0 mol% Dy was assigned to the lower crystallite size, higher surface area and pore volume, higher acidity strength and the greatest dysprosium load.
One-pot synthesis at room temperature of epoxides and linalool derivative pyrans in monolacunary Na7PW11O39-catalyzed oxidation reactions by hydrogen peroxide
Da Silva, Márcio J.,Teixeira, Milena Galdino,Vilanculo, Castelo B.,Villarreal, Jesus Avendano
, p. 7691 - 7697 (2020/03/10)
In this work, we describe a new one-pot synthesis route of valuable linalool oxidation derivatives (i.e., 2-(5-methyl-5-vinyltetrahydrofuran-2-yl propan-2-ol) (1a)), 2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran-3-ol (1b) and diepoxide (1c), using a green oxidant (i.e., hydrogen peroxide) under mild conditions (i.e., room temperature). Lacunar Keggin heteropolyacid salts were the catalysts investigated in this reaction. Among them, Na7PW11O39 was the most active and selective toward oxidation products. All the catalysts were characterized by FT-IR, TG/DSC, BET, XRD analyses and potentiometric titration. The main reaction parameters were assessed. Special attention was dedicated to correlating the composition and properties of the catalysts and their activity.
Unraveling the role of the lacunar Na7PW11O39 catalyst in the oxidation of terpene alcohols with hydrogen peroxide at room temperature
Vilanculo, Castelo B.,Da Silva, Márcio J.
, p. 2813 - 2820 (2020/03/03)
In this work, we have assessed the activity of various Keggin heteropolyacid (HPA) salts in a new one-pot synthesis route of valuable products, which were obtained from the oxidation of terpenic alcohols (i.e., aldehyde, epoxide, and diepoxide), using a green oxidant (i.e., hydrogen peroxide) at mild conditions (i.e., room temperature). Lacunar Keggin HPA sodium salts were the goal catalysts investigated in this reaction. Starting from the HPAs (H3PW12O40, H3PMo12O40, and H4SiW12O40), we synthesized lacunar sodium salts (Na7PW11O39, Na7PW11O39 and Na8SiW11O39) and a saturated salt (Na3PW12O40). All of them were investigated in oxidation reactions in a homogeneous phase with nerol as a model molecule. Na7PW11O39 was the most active and selective towards the oxidation products. All the catalysts were characterized by FT-IR, TG/DSC, BET, XRD, and SEM-EDS analyses and potentiometric titration. The main reaction parameters were assessed. Geraniol, α-terpineol, β-citronellol and borneol were also successfully oxidized. Special attention was dedicated to correlating the composition and properties of the catalysts with their activity.
Method for synthesizing carvacrol from dipentene dioxide
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Paragraph 0017; 0019; 0021; 0022, (2019/01/24)
The invention discloses a method for synthesizing carvacrol from dipentene dioxide. The method comprises the following steps: step 1, utilizing the dipentene dioxide as a raw material and reducing thedipentene dioxide in a solvent A through a sodium borohydride water solution to obtain alpha,alpha,6-trimethyl-7-oxa bicyclo(4.1.0)heptane-3-methyl alcohol and 1,3,3-trimethyl-2-oxa bicyclo(2.2.2)octane-6-alcohol; step 2, dehydrating and rearranging the alpha,alpha,6-trimethyl-7-oxa bicyclo(4.1.0)heptane-3-methyl alcohol and 1,3,3-trimethyl-2-oxa bicyclo(2.2.2)octane-6-alcohol which are obtainedin step 1 through acid catalysis to obtain iso-dihydrocarvone; step 3, dissolving the iso-dihydrocarvone obtained in step 2 and a carbon-based compound catalyst into a solvent and heating the mixtureto generate dehydrogenation oxidation reaction, generating carvacrol, filtering the carvocrol to separate the carbon-based compound catalyst and performing reduced pressure rectification on filtrate to obtain a carvacrol finished product. The acid, the carbon-based compound catalyst and the solvent in the method disclosed by the invention all can be recycled, so that cost is reduced; the raw material of the dipentene dioxide in the method disclosed by the invention is an auxiliary product of the company, so that regeneration and comprehensive utilization of byproducts are achieved, and economic value of the byproducts is improved.
Method for synthesizing carvacrol from dipentene dioxide
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Paragraph 0014; 0016; 0017; 0018, (2019/01/24)
The invention discloses a method for synthesizing carvacrol from dipentene dioxide. The method comprises the following steps: step 1, utilizing the dipentene dioxide as a raw material and performing reducing reaction in a solvent A through the action of ammonium formate to obtain alpha,alpha,6-trimethyl-7-oxa bicyclo(4.1.0)heptane-3-methyl alcohol under the situations of hydrogen pressurization and utilizing Pd/C as a catalyst; step 2, performing dehydrating and rearranging reaction on the alpha,alpha,6-trimethyl-7-oxa bicyclo(4.1.0)heptane-3-methyl alcohol obtained in step 1 under acid catalysis to obtain iso-dihydrocarvone; step 3, dissolving the iso-dihydrocarvone obtained in step 2 and a carbon-based compound catalyst into a solvent and heating the mixture to generate dehydrogenation oxidation reaction, generating carvacrol, filtering the carvacrol to separate the carbon-based compound catalyst and performing reduced pressure rectification on filtrate to obtain a carvacrol finishedproduct. The Pd/C, the acid, the carbon-based compound catalyst and the solvent in the method disclosed by the invention can all be recycled, so that cost is reduced; the raw material of the dipentene dioxide in the method disclosed by the invention is an auxiliary product of the company, so that regeneration and comprehensive utilization of byproducts are achieved, and economic value of the byproducts is improved.
Catalytic epoxidation using dioxidomolybdenum(VI) complexes with tridentate aminoalcohol phenol ligands
Hossain, Md. Kamal,Schachner, J?rg A.,Haukka, Matti,M?sch-Zanetti, Nadia C.,Nordlander, Ebbe,Lehtonen, Ari
, p. 17 - 25 (2018/10/24)
Reaction of the tridentate aminoalcohol phenol ligands 2,4-di-tert-butyl-6-(((2 hydroxyethyl)(methyl)amino)methyl)phenol (H2L1) and 2,4-di-tert-butyl-6-(((1-hydroxybutan-2-yl)amino)methyl)phenol (H2L2) with [MoO2(acac)2] in methanol solutions resulted in the formation of [MoO2(L1)(MeOH)] (1) and [MoO2(L2)(MeOH)] (3), respectively. In contrast, the analogous reactions in acetonitrile afforded the dinuclear complexes [Mo2O2(μ-O)2(L1)2] (2) and [Mo2O2(μ-O)2(L2)2] (4). The corresponding reactions with the potentially tetradentate ligand 3-((3,5-di-tert-butyl-2-hydroxybenzyl)(methyl)amino)propane-1,2-diol (H3L3) led to the formation of the mononuclear complex [MoO2(L3)(MeOH)] (5) in methanol while in acetonitrile solution a trinuclear structure [Mo3O3(μ-O)3(L3)3] (6) was obtained. In both cases, the ligand moiety L3 coordinated in a tridentate fashion. The catalytic activities of complexes 1–6 in epoxidation of five different olefins, S1-5, with tert-butyl hydroperoxide and hydrogen peroxide were studied. The catalytic activities were found to be moderate to good for the reaction of substrate cis-cyclooctene S1, while all complexes were less active in the epoxidation of the more challenging substrates S2-5. The molecular structures of 1, 2, 4 and 6 were determined by single crystal X-ray diffraction analyses.
Dioxidomolybdenum(VI) and -tungsten(VI) complexes with tripodal amino bisphenolate ligands as epoxidation and oxo-transfer catalysts
Hossain, Md. Kamal,Schachner, J?rg A.,Haukka, Matti,Lehtonen, Ari,M?sch-Zanetti, Nadia C.,Nordlander, Ebbe
, p. 275 - 281 (2017/07/13)
The molybdenum(VI) and tungsten(VI) complexes [MO2(L)] (M?=?Mo (1), W (2), H2L?=?bis(2-hydroxy-3,5-di-tert-butybenzyl)morpholinylethylamine) were synthesized and the complexes were used to catalyze oxotransfer reactions, viz. sulfoxi
Hydrogen bond donor functionalized dioxido-molybdenum(VI) complexes as robust and highly efficient precatalysts for alkene epoxidation
Zwettler, Niklas,Schachner, J?rg A.,Belaj, Ferdinand,M?sch-Zanetti, Nadia C.
, p. 209 - 219 (2017/11/15)
The synthesis of four novel, tridentate aminophenolate ligands HL1-HL4, bearing amide functionalities is reported. Reaction of these ligands with a dioxido molybdenum(VI) precursor led, depending on the choice of solvent, to mononuclear complexes of the type [MoO2L(OMe)] (2, 4, 6) or dinuclear complexes [{MoO2L}2(μ-O)] (1, 3, 5, 7), containing one facially, tridentate ONO-ligand per metal center. This synthetic discrimination between dinuclear and mononuclear complexes allows for a comparison between structures and reactivity. Complexes 1-7 were found to be highly active catalysts in the epoxidation of several internal and terminal alkenes. With tert-butyl hydroperoxide (TBHP) as oxidant, precatalyst loadings of 0.0005 mol% (5 ppm) could be realized leading to turnover numbers of up to 110000. The precatalysts also allowed for the use of hydrogen peroxide (0.1 mol% precatalyst) as oxidant as well as various alcohols as “green” solvents, such as ethanol or even tert-butanol (usually an inhibitor of epoxidation).
Dioxomolybdenum(VI) and -tungsten(VI) Complexes with Multidentate Aminobisphenol Ligands as Catalysts for Olefin Epoxidation
Dup, Antoine,Hossain, Md. Kamal,Schachner, J?rg A.,Belaj, Ferdinand,Lehtonen, Ari,Nordlander, Ebbe,M?sch-Zanetti, Nadia C.
, p. 3572 - 3579 (2015/08/06)
The synthesis of four molybdenum and tungsten complexes bearing tetradentate tripodal amino bisphenolate ligands with either hydroxyethylene (1a) or hydroxyglycolene (1b) substituents is reported. The molybdenum dioxo complexes [MoO2L] (L = 2a, 2b) and tungsten complexes [WO2L] (3a, 3b) were synthesized using [MoO2(acac)2] and [W(eg)3] (eg = 1,2-ethanediolato, ethylene glycolate), respectively, as precursors. All complexes were characterized by spectroscopic means as well as by single-crystal X-ray diffraction analyses. The latter reveal, in all cases, hexacoordinate complexes in which the hydrogen atom of the hydroxy group is involved in hydrogen bonding with one of the metal oxo groups. In the case of the glycol substituent, the ether oxygen atom is coordinated to the metal whereas the hydroxy group remains uncoordinated. The complexes were tested as catalysts in the epoxidation of cyclooctene under eco-friendly conditions, using an aqueous solution of H2O2 as the oxidant and dimethyl carbonate (DMC) as solvent or neat conditions, as substitutes for chlorinated solvents. Molybdenum complexes 2a and 2b showed good catalytic activity using H2O2 without added solvent, and tungsten complexes 3a and 3b showed very high activity in the epoxidation of cyclooctene using H2O2 and DMC as solvents. Four new molybdenum and tungsten complexes bearing tetradentate tripodal amino bisphenolate ligands with either hydroxyethylene or hydroxyglycolene substituents were synthesized and found to catalyze olefin epoxidation reactions under eco-friendly conditions.
An ionic liquid immobilized copper complex for catalytic epoxidation
Dileep,Rudresha
, p. 65870 - 65873 (2015/08/18)
This article brings into focus an in situ strategy of immobilization of a copper complex onto an ionic liquid support. A practical method of olefin and terpene epoxidation by immobilizing a copper complex and 1-ethyl-3-methylimidazolium hexafluorophosphate and using H2O2 as the terminal oxidant is developed. The advantageous properties of this catalytic system redefine an exceptionally clean environment for catalytic epoxidations.
