105-37-3Relevant articles and documents
Effect of functional groups in organic chlorides on radical reduction with hydrostannane under microwave irradiation
Nishimoto, Yoshihiro,Yazawa, Satoshi,Kiyokawa, Kensuke,Kajiki, Takahito,Tsukahara, Yasunori,Yamauchi, Tomohisa,Wada, Yuji,Baba, Akio,Yasuda, Makoto
, p. 1116 - 1118 (2017)
The effect of functional groups on the activation of molecules by microwave irradiation in the reduction of organic chlorides by Bu3SnH was investigated. The reactivity of a substrate with a hydroxy group increased under microwave heating conditions in comparison with conventional heating.
DECOMPOSITION OF THE PEROXIDES OF THE ESTERS OF KETO ACIDS BY Fe(II) SALTS
Starostin, E. K.,Radyukin, Yu. N.,Ignatenko, A. V.,Nikishin, G. I.
, p. 109 - 112 (1980)
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High density monolayer of diisocyanide on gold surface as a platform of supported Rh-catalyst for selective 1,4-hydrogenation of α,β- unsaturated carbonyl compounds
Jagtap,Kaji,Fukuoka,Hara
, p. 5046 - 5048 (2014)
A high density monolayer of diisocyanide on gold surface was utilized as a platform of supported Rh catalyst for selective 1,4-hydrogenation of α,β-unsaturated carbonyl compounds. The catalyst exhibited high turnover numbers in a range of 50-000 to 150-000 per Rh atom and showed steady catalyst performance over six recycle usages.
Magnetically recoverable AlFe/Te nanocomposite as a new catalyst for the facile esterification reaction under neat conditions
Alavi, Seyed Jamal,Sadeghian, Hamid,Seyedi, Seyed Mohammad,Eshghi, Hossein,Salimi, Alireza
, (2018)
In this work, a new Fe3O4/AlFe/Te nanocomposite was synthesized by a one-step sol–gel method. The Fe3O4 magnetic nanoparticles (MNPs) were prepared and then mixed with aluminum telluride (Al2Te3) in an alkali medium to produce the desired catalyst. After characterization of the Fe3O4/AlFe/Te nanocomposite by SEM, TEM, EDS, XRD, and ICP analyses, it was used in the esterification reaction. This heterogeneous catalyst showed high catalytic activity in the esterification of commercially available carboxylic acids with various alcohols to produce the desired esters at high conversions under neat conditions. The Fe3O4/AlFe/Te nanocomposites were separated from the reaction mixture via an external magnet and re-used 8 times without significant loss of catalytic activity.
Catalytic Reaction of Methanol with a Series of Ruthenium(II) Complexes and the Mechanism of the Formation of Acetic Acid from Methanol Alone
Yamakawa, Tetsu,Hiroi, Masayuki,Shinoda, Sumio
, p. 2265 - 2270 (1994)
The catalytic abilities of a series of ruthenium(II) complexes containing zero, one and two SnCl3(1-) ligands, 4> 1, 4> 2 and 3> 3, have been compared in the reaction of methanol to form acetic acid (and/or methyl acetate due to esterification), as well as their reactions with the possible intermediates (formaldehyde, methyl formate) in the overall reaction.It was found that the formation of acetic acid from methanol occured only with 3, which also converted paraformaldehyde or methyl formate into acetic acid.Complex 1 showed only a catalytic activity for the Tischenko-type dimerization (2 HCHO -> HCO2Me), and 2 exhibited an intermediate character, being able to catalyse the two reactions (2 HCHO -> HCO2Me, HCO2Me -> MeCO2H) but unable to react with methanol.Based on kinetic results for the reaction of methanol with 3, a possible reaction pathway is proposed where methyl formate and acetic acid are formed from formaldehyde competitively sharing a common reaction path.For the isomerization of methyl formate as a substrate a separate reaction path is suggested, where the Ru(II)-Sn(II) bimetallic centre of 2 and 3 converts the co-ordinated HCO2Me into a five-membered acetate bridge.
Efficient palladium and ruthenium nanocatalysts stabilized by phosphine functionalized ionic liquid for selective hydrogenation
Wu, Zhifeng,Jiang, Heyan
, p. 34622 - 34629 (2015)
Pd and Ru nanoparticles were synthesized in ionic liquid by using tri(m-sulfonyl)triphenyl phosphine 1-butyl-2,3-dimethyl-imidazolium salt ([BMMIM]3[tppt]) as a stabilizing agent. The well-dispersed Pd and Ru NPs with mean diameters of 2.4 nm and 1.7 nm were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). It was demonstrated that [BMMIM]3[tppt] stabilized Pd and Ru NPs displayed high activity and excellent selectivity in the hydrogenation of functionalized olefins, aromatic nitro compounds and aromatic aldehydes. The Pd and Ru NPs showed better catalytic performance than corresponding commercially available Pd/C and Ru/C catalysts. The present catalytic system could be easily reused at least six times without significant decrease in activity and selectivity.
Oxidative functionalization of methane in the presence of a homogeneous rhodium-copper-chloride catalytic system: Transformation of acetic and propionic acids as solvent components
Chepaikin,Bezruchenko,Menchikova,Moiseeva,Gekhman,Moiseev
, p. 133 - 142 (2011)
The oxidative functionalization of methane (O2, CO, 95°C, Rh III/CuI, II/Cl- catalytic system) was studied in an aqueous acetic or propionic acid medium. It was shown that oxidative decarbonylation of carboxylic acids takes place along with methanol and methyl carboxylate formation.
Enolate Anions. 2. Reaction between Potassium Solutions Containing Crown Ethers and β-Lactones
Jedlinski, Z.,Misiolek, A.,Kurcok, P.
, p. 1500 - 1501 (1989)
A novel fission of the α carbon to β carbon by the treatment of β-lactones with potassium solutions containing crown ether is reported.The enolate carbanion formed, upon subsequent treatment with HCl or methyl iodide yielded respective esters.
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Newitt,Momen
, p. 2945,2947 (1949)
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Rapid degradation of cyclic peroxides by titanium and antimony chlorides
Bali, Mark S.,Armitt, David,Wallace, Lynne,Day, Anthony I.
, p. 6775 - 6783 (2015)
First responders face extraordinary risks when dealing with organic peroxides such as TATP due to the extreme sensitivity of this class of explosives, and to a lack of a robust chemical means of safe and rapid neutralisation. The Lewis acids TiCl4 and SbCl3 have been found to demonstrate a novel degradation mechanism, with TiCl4 degrading a model cyclic peroxide in minutes when used in a two-fold excess, or ～3 hours at half equivalence. The products cannot re-form peroxide compounds as is the case with acid degradation, suggesting the two mechanisms are fundamentally different. The Lewis acids mediate a rearrangement reaction in the cyclic peroxide backbone leading to relatively innocuous products through deactivation of oxidising O. Sub-stoichiometric TiCl4 reactions highlight a secondary reaction pathway that also leads to some oxidative chlorination products, possibly mediated by an unconfirmed titanium-oxychloride species. SbCl3 was found to exhibit similar reactivity to TiCl4, although at a slower rate. A mechanism is proposed, consistent with the observations for both stoichiometric and sub-stoichiometric quantities of TiCl4.
EQUILIBRIA BETWEEN MexSiCl4-x, x = 3,2,1,0 AND ALKYL CARBOXYLATE ESTERS
Mbah, Godfrey C.,Speier, John L.
, p. 77 - 82 (1984)
At 150 deg C equilibria are established between chlorosilanes and alkyl esters according to the equation: MexSiCl4-x + RCOOR' MexSi(O0.5)y(OOCR)z-yCl4-x-y-z + yRCOCl + zR'Cl.When x = 3, y = 0, z = 0.56; when x = 2, y = 0.26, z = 0.98.When x = 1, y = z = 0.56; when x = 0, y = z = 0.53.Lewis acid salts such as ZnCl2 or FeCl3 are effective catalysts for the reactions leading to mixtures of these compounds.
Relative Bond Dissociation Energies for Two-Ligand Complexes of Cu+ with Organic Molecules in the Gas Phase
Jones, Roger W.,Staley, Ralph H.
, p. 2296 - 2300 (1982)
Ralative two-ligand dissociation enthalpies, δD(Cu+-2L), for Cu+ with 43 organic molecules are determined.A pulsed-laser volatilization/ionization sourse is used to generate Cu+ which reacts with EtCl and/or other molecules to give Cu(ligand)2+ species.Equilibrium constants are measured for the ligand-exchange reactions which occur when pairs of ligand molecules are present.Free energies for two-ligand exchange are obtained from the equilibrium constant for the reaction Cu(A)2+ + 2B ->/+ + 2A.The free-energiy differences are added to give a scale of relative free energies for ligand exchange.These are converted to enthalpies to give δD(Cu+-2L) scale with the assumption that enthropy changes are small and can be neglected except for symmetry corrections which are made in appropriate cases.Dependence of δD(Cu+-2L) on functional group and substituent effects is analyzed.These results for Cu+ are compared to available results for other reference acids: H+, Al+, Mn+, Li+, and CpNi+.These comparisons show that Cu+ is a softer acid than the other reference acids.This is apparent from the relative preference of Cu+ for mercaptans and HCN compared to alcohols and other oxygen bases.
Predicting the Solvent Effect on Esterification Kinetics
Lemberg, Max,Sadowski, Gabriele
, p. 1977 - 1980 (2017)
It is well known that solvents influence reaction kinetics. The classical concentration-based kinetic modeling is unable to describe these effects. In this work, the reaction kinetics was studied for the esterifications of acetic acid and propionic acid with ethanol at 303.15 K. It was found that the reactant ratio as well as the applied solvents (acetonitrile, tetrahydrofurane, dimethylformamide) significantly affect the reaction rate. The thermodynamic model PC-SAFT was applied to account for the interactions between the reacting species and the solvents via activity coefficients. This allowed the identification of solvent-independent kinetic constants and the prediction of the solvent effect on reaction kinetics in almost quantitative agreement with experimental data. The presented approach shows the importance of taking into account thermodynamic non-idealities and significantly reduces experimental effort for finding the best solvent candidate for a given target reaction.
Highly conserved progesterone 5β-reductase genes (P5βR) from 5β-cardenolide-free and 5β-cardenolide-producing angiosperms
Bauer, Peter,Munkert, Jennifer,Brydziun, Margareta,Burda, Edyta,Müller-Uri, Frieder,Gr?ger, Harald,Muller, Yves A.,Kreis, Wolfgang
, p. 1495 - 1505 (2010)
Most cardenolides used in the therapy of cardiac insufficiency are 5β-configured and thus the stereo-specific reduction of the Δ4,5-double bond of a steroid precursor is a crucial step in their biosynthesis. This step is thought to be catalysed by progesterone 5β-reductases. We report here on the isolation of 11 progesterone 5β-reductase (P5βR) orthologues from 5β-cardenolide-free and 5β-cardenolide-producing plant species belonging to five different angiosperm orders (Brassicales, Gentianales, Lamiales, Malvales and Solanales). Amino acid sequences of the P5βR described here were highly conserved. They all contain certain motifs qualifying them as members of a class of stereo-selective enone reductases capable of reducing activated CC double bonds by a 1,4-addition mechanism. Protein modeling revealed seven conserved amino acids in the substrate-binding/catalytic site of these enzymes which are all supposed to exhibit low substrate specificity. Eight P5βR genes isolated were expressed in Escherichia coli. Recombinant enzymes reduced progesterone stereo-specifically to 5β-pregane-3,20-dione. The progesterone 5β-reductases from Digitalis canariensis and Arabidopsis thaliana reduced activated CC double bonds of molecules much smaller than progesterone. The specific role of progesterone 5β-reductases of P5βRs in cardenolide metabolism is challenged because this class of enone reductases is widespread in higher plants, and they accept a wide range of enone substrates.
Comparison of the performance of commercial immobilized lipases in the synthesis of different flavor esters
Martins, Andrea B.,Da Silva, Alexandre M.,Schein, Mirela F.,Garcia-Galan, Cristina,Zachia Ayub, Marco A.,Fernandez-Lafuente, Roberto,Rodrigues, Rafael C.
, p. 18 - 25 (2014)
In this work, it is compared the performance of three commercial lipase preparations (Novozym 435, Lipozyme TL-IM, and Lipozyme RM-IM) in the synthesis of flavor esters obtained by esterification of acetic, propionic, and butyric acids using ethanol, isopropyl alcohol, butanol, or pentanol. A comprehensive comparison was performed verifying activities of these three enzyme preparations versus the different couples of substrates, checking the obtained yields. In general, the longer the acid chain, the higher the reaction yields. Novozym 435 was the most efficient enzyme in most cases, and only Lipozyme RM-IM offered better results than Novozym 435 in the production of ethyl butyrate. Reactions with butyric acid showed the highest conversion rates using all biocatalysts. Using optimal substrates, the reactions catalyzed by the three enzymes were optimized using the response surface methodology, and the catalytic performance of the biocatalysts in repeated batches was assessed. After optimization, yields higher than 90% were obtained for all three enzymes, but Lipozyme TL-IM needed four-times more biocatalyst content than the other two preparations. Novozym 435 kept over 80% of its activity when reused in 9 successive batches, whereas Lipozyme RM-IM can be reused 5 times and Lipozyme TL-IM only 3 times. In general, Novozym 435 showed to be more suitable for these reactions than the other two enzyme preparations.
Dehalogenation of α-Halo Carbonyl Compounds by a New Efficient Reagent, Triphenylphosphonium Iodide
Kamiya, Naoshi,Tanmatu, Hiroshi,Ishii, Yasutaka
, p. 293 - 296 (1992)
Triphenylphosphonium iodide, Ph3PHI, was found to be an efficient reagent for the dehalogenation of α-halo carbonyl compounds. α-Halo esters, which were difficult to be reduced with Me3SiCl/NaI reagent, was smoothly debromiated by Ph3PHI.Treatment of α-halocarbonyl compounds with Ph3PDI produced the corresponding α-deuterated compounds.
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Dippy,Parkins
, p. 1570,1573 (1951)
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Synthesis, characterization and catalytic performance of a novel picolinic acid-12-molybdophosphoric acid hybrid catalyst
Liu, Lijun,Wang, Honghong,Gong, Shuwen,Lu, Jing,Zhang, Qian
, p. 1007 - 1013 (2016)
A novel 12-molybdophosphoric acid (HPM)-based complex (H2 PI)2(H 3 O)[PMo12O 40] [Mo2 O5 (H2 O)2 (PI)2 ]?11H2 O (PI-HPM) was prepared by modification with picolinic acid (HPI) and characterized by the methods of Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG), X-ray powder and single crystal diffraction. The complex retained the classical Keggin structure of bulk HPM, there were some strong hydrogen bonds existing between the [PMo12 O40 ]3- polyanion, the [Mo2 O5 (H2 O)2 (PI)2 ] coordination moiety, the protonated HPI and the lattice water molecules. Then PI-HPM was employed as heterogeneous catalyst for esterification reaction to evaluate its acid-catalytic activity. The complex exhibited high activity and good durability in reaction mixtures, indicating that it was a promising heterogeneous acid catalyst for esterification that including the conversion of oleic acid to oleates.
ZrOCl2·8H2O: An efficient, cheap and reusable catalyst for the esterification of acrylic acid and other carboxylic acids with equimolar amounts of alcohols
Sun, Hong-Bin,Hua, Ruimao,Yin, Yingwu
, p. 263 - 271 (2006)
Esterifications of carboxylic acids with equimolar amount of alcohols could be efficiently catalyzed by ZrOCl2·8H2O. Acrylate esters were obtained in good yields under solvent-free conditions at ambient temperature. The esterification of other carboxylic acids with alcohols also proceeded at ambient temperature or at 50°C to afford esters in high yields. If the esterification was performed in toluene under azeotropic reflux conditions to remove water, both the catalytic activity of ZrOCl 2·8H2O and the rate of esterification could be increased greatly. Furthermore, in the present catalytic system, the esters could be easily separated from the reaction mixtures and the catalyst could be easily recovered and reused.
Carbonylation of alcohols in the Pd(OAc)2/TsOH/molten salt system
Eliseev, Oleg L.,Bondarenko, Tatyana N.,Stepin, Nikolai N.,Lapidus, Albert L.
, p. 107 - 109 (2006)
A non-phosphine catalytic system, Pd(OAc)2/TsOH/NBu 4Br, is suggested for the synthesis of acids by the carbonylation of alcohols.
The Double Carbonylation of Diiodomethane Catalysed by Rhodium Complexes
Weston, William S.,Gash, Rosslyn C.,Cole-Hamilton, David J.
, p. 745 - 746 (1994)
In alcohols, ROH, in the presence of and optionally also in the presence of a tertiary phosphorus ligand PR'3, CH2I2 reacts with CO to give CH2(CO2R)2, CH2(OR)2 and RI.
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Beckham,Adkins
, p. 2676,2678 (1934)
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A HIGH YIELD ROUTE TO ETHYL ESTERS OF CARBOXYLIC ACIDS
Downie, Ian M.,Wynne, Neil,Harrison, Stephen
, p. 1457 - 1458 (1982)
Diethyl trichloromethylphosphonate reacts with carboxylic acids to yield their ethyl esters, via transesterification; even the hindered mesitoic acid is esterified in high yield.
Vapor-phase ethanol carbonylation with heteropolyacid-supported Rh
Yacob, Sara,Park, Sunyoung,Kilos, Beata A.,Barton, David G.,Notestein, Justin M.
, p. 1 - 8 (2015)
Ethanol carbonylation is a potential route to valuable C3 products. Here, Rh supported on porous, Cs-exchanged heteropolyacid Cs3PW12O40, is demonstrated as an effective catalyst for vapor-phase ethanol carbonylation, with higher selectivity and conversion to propionates than existing catalysts. Residual acidity or a Mo polyatom was strongly detrimental to yields. Propionate selectivity was maximized at 96% at 170 °C and with added H2O. The catalyst displayed stable selectivity over 30 h on stream and up to 77% conversion. Ethyl iodide is a required co-catalyst but at levels as low as 2% relative to ethanol. XPS and in situ XANES indicate partial Rh reduction, consistent with the formation of low-valent reactive intermediates and slow deactivation through formation of Rh nanoparticles. With further optimization and understanding, these Rh/heteropolyacid catalysts may lead to stable and selective catalysts for the production of propionates through ethanol carbonylation.
Conjugate hydrostannation of unsaturated esters by iodotin hydride ate complex
Shibata,Suwa,Ryu,Baba
, p. 8690 - 8692 (2001)
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Design, Synthesis, and Study of the Insecticidal Activity of Novel Steroidal 1,3,4-Oxadiazoles
Bai, Hangyu,Jiang, Weiqi,Li, Qi,Li, Tian,Ma, Shichuang,Shi, Baojun,Wu, Wenjun
, p. 11572 - 11581 (2021/10/12)
A series of novel steroidal derivatives with a substituted 1,3,4-oxadiazole structure was designed and synthesized, and the target compounds were evaluated for their insecticidal activity against five aphid species. Most of the tested compounds exhibited potent insecticidal activity against Eriosoma lanigerum (Hausmann), Myzus persicae, and Aphis citricola. Compounds 20g and 24g displayed the highest activity against E. lanigerum, showing LC50 values of 27.6 and 30.4 μg/mL, respectively. Ultrastructural changes in the midgut cells of E. lanigerum were detected by transmission electron microscopy, indicating that these steroidal oxazole derivatives might exert their insecticidal activity by destroying the mitochondria and nuclear membranes in insect midgut cells. Furthermore, a field trial showed that compound 20g exhibited effects similar to those of the positive controls chlorpyrifos and thiamethoxam against E. lanigerum, reaching a control rate of 89.5% at a dose of 200 μg/mL after 21 days. We also investigated the hydrolysis and metabolism of the target compounds in E. lanigerum by assaying the activities of three insecticide-detoxifying enzymes. Compound 20g at 50 μg/mL exhibited inhibitory action on carboxylesterase similar to the known inhibitor triphenyl phosphate. The above results demonstrate the potential of these steroidal oxazole derivatives to be developed as novel pesticides.
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.
