20515-19-9Relevant articles and documents
Methyl 4-methoxypentanoate: A novel and potential downstream chemical of biomass derived gamma-valerolactone
Li, Zheng,Jiang, Yetao,Tang, Xing,Zuo, Miao,Zeng, Xianhai,Sun, Yong,Lin, Lu
, p. 8297 - 8300 (2015)
Lignocellulosic derived gamma-valerolactone was effectively converted into methyl 4-methoxypentanoate, a potential liquid biofuel, solvent and fragrance, by the catalysis of a hydrogen exchanged ultra-stable Y zeolite (HUSY) and insoluble carbonates such as CaCO3. The catalytic competing generation process between methyl 4-methoxypentanoate and pentenoate esters was also analysed.
C-C-VERKNUEPFUNG VON ALKENEN MIT CO2 AN NICKEL(0); n-PENTENSAEUREN AUS ETHEN
Hoberg, Heinz,Peres, Yolande,Milchereit, Armin
, p. C41 - C43 (1986)
Ethene undergoes oxidative coupling reactions with CO2 and (Lig)Ni0 systems to give oxanickela complexes.Under suitable conditions depending on the temperature and ethene pressure, isomers of pentenoic acid are formed in high yield.
Electrochemical reduction of CO2 in the presence of 1,3-butadiene using a hydrogen anode in a nonaqueous medium
Grinberg, V. A.,Koch, T. A.,Mazin, V. M.,Mysov, E. I.,Sterlin, S. R.
, p. 294 - 299 (1999)
The possibility or anodic generation of a solvated proton on gas-diffusion electrode in an aprotic medium in the presence of carbon dioxide and 1,3-butadiene has been demonstrated. Formic acid was shown to be the only product of the reaction in the initially approtic medium with the use of a hydrogen gas-diffusion anode. The influence of the counterion on the reactivity of the CO2*- radical anion in electrocarboxylation was shown experimentally.
Palladium-Catalyzed Methoxycarbonylation of 1,3-Butadiene to Methyl-3-Pentenoate: Introduction of a Continuous Process
Han, Li-Jun,Ma, Shuang-Shuang,Rao, Chong-Shun,Sheng, Gui-Yang,Xu, Bao-Hua,Zhang, Jun-Ping
, p. 283 - 290 (2021/10/27)
The base-assisted Pd(cod)Cl2/Xantphos-catalyzed methoxycarbonylation of 1,3-butadiene (BD) to methyl-3-pentenoate (MP) was explored. Mechanistic studies suggest the excessive Xantphos (beyond an equimolar amount per Pd) as well as its substitute, pyridines of proper steric and electronic functionality, do participate the catalytic cycle and significantly reduce the activation energy by accelerating the rate-limiting methanolysis step. As thus, all the reaction parameters, especially the solvents, were optimized based on the Pd(cod)Cl2/Xantphos/4-hexylpyridine catalytic system, enabling the construction of a continuous process. Systematic optimization demonstrates that a yield of 82% of MP with a purity of 99.8% could be reached under steady-state operation.
Directing Selectivity to Aldehydes, Alcohols, or Esters with Diphobane Ligands in Pd-Catalyzed Alkene Carbonylations
Aitipamula, Srinivasulu,Britovsek, George J. P.,Nobbs, James D.,Tay, Dillon W. P.,Van Meurs, Martin
, p. 1914 - 1925 (2021/06/28)
Phenylene-bridged diphobane ligands with different substituents (CF3, H, OMe, (OMe)2, tBu) have been synthesized and applied as ligands in palladium-catalyzed carbonylation reactions of various alkenes. The performance of these ligands in terms of selectivity in hydroformylation versus alkoxycarbonylation has been studied using 1-hexene, 1-octene, and methyl pentenoates as substrates, and the results have been compared with the ethylene-bridged diphobane ligand (BCOPE). Hydroformylation of 1-octene in the protic solvent 2-ethyl hexanol results in a competition between hydroformylation and alkoxycarbonylation, whereby the phenylene-bridged ligands, in particular, the trifluoromethylphenylene-bridged diphobane L1 with an electron-withdrawing substituent, lead to ester products via alkoxycarbonylation, whereas BCOPE gives predominantly alcohol products (n-nonanol and isomers) via reductive hydroformylation. The preference of BCOPE for reductive hydroformylation is also seen in the hydroformylation of 1-hexene in diglyme as the solvent, producing heptanol as the major product, whereas phenylene-bridged ligands show much lower activities in this case. The phenylene-bridged ligands show excellent performance in the methoxycarbonylation of 1-octene to methyl nonanoate, significantly better than BCOPE, the opposite trend seen in hydroformylation activity with these ligands. Studies on the hydroformylation of functionalized alkenes such as 4-methyl pentenoate with phenylene-bridged ligands versus BCOPE showed that also in this case, BCOPE directs product selectivity toward alcohols, while phenylene-bridge diphobane L2 favors aldehyde formation. In addition to ligand effects, product selectivities are also determined by the nature and the amount of the acid cocatalyst used, which can affect substrate and aldehyde hydrogenation as well as double bond isomerization.
Method for enhancing long-chain olefin hydrogen esterification reaction by ionic liquid
-
Paragraph 0039-0064, (2021/06/13)
The invention relates to a method for preparing carboxylic ester through long-chain olefin hydrogen esterification reaction. The method is characterized by comprising the following steps: mixing long-chain olefin of which the C number is greater than or equal to 4 with a catalyst, a carbonyl source and alkyl alcohol according to a certain ratio, and carrying out hydrogen esterification reaction in a high-boiling-point solvent such as ester, ketone, ether, amide, aromatic hydrocarbon, sulfone (sulfoxide) or conventional ionic liquid. The first ligand is a bidentate phosphine ligand, and the second ligand is an ionic liquid containing a single-coordination central atom (N, P). The method has the advantages that raw material gas and liquid phases can be in full contact, the catalyst and a high-boiling-point solvent system can be recycled, and rapid separation of the catalyst and a product is achieved. In the conjugated olefin hydrogen esterification reaction, the olefin conversion rate is more than 80%, and the product selectivity is more than 85%; in the monoolefine hydrogen esterification reaction, the olefin conversion rate is greater than 90%, and the product selectivity is greater than 95%.
Modulation of N^N′-bidentate chelating pyridyl-pyridylidene amide ligands offers mechanistic insights into Pd-catalysed ethylene/methyl acrylate copolymerisation
ó Máille, Gearóid M.,Albrecht, Martin,Dall'Anese, Anna,Grossenbacher, Philipp,Milani, Barbara,Montini, Tiziano
, p. 6133 - 6145 (2021/05/19)
The efficient copolymerisation of functionalised olefins with alkenes continues to offer considerable challenges to catalyst design. Based on recent work using palladium complexes containing a dissymmetric N^N′-bidentate pyridyl-PYA ligand (PYA = pyridylidene amide), which showed a high propensity to insert methyl acrylate, we have here modified this catalyst structure by inserting shielding groups either into the pyridyl fragment, or the PYA unit, or both to avoid fast β-hydrogen elimination. While a phenyl substituent at the pyridyl side impedes catalytic activity completely and leads to an off-cycle cyclometallation, the introduction of an ortho-methyl group on the PYA side of the N^N′-ligand was more prolific and doubled the catalytic productivity. Mechanistic investigations with this ligand system indicated the stabilisation of a 4-membered metallacycle intermediate at room temperature, which has previously been postulated and detected only at 173 K, but never observed at ambient temperature so far. This intermediate was characterised by solution NMR spectroscopy and rationalises, in part, the formation of α,β-unsaturated esters under catalytic conditions, thus providing useful principles for optimised catalyst design.
Olefin Dimerization and Isomerization Catalyzed by Pyridylidene Amide Palladium Complexes
Navarro, Miquel,Rosar, Vera,Montini, Tiziano,Milani, Barbara,Albrecht, Martin
, p. 3619 - 3630 (2018/10/05)
A series of cationic palladium complexes [Pd(N^N′)Me(NCMe)]+ was synthesized, comprising three different N^N′-bidentate coordinating pyridyl-pyridylidene amide (PYA) ligands with different electronic and structural properties depending on the PYA position (o-, m-, and p-PYA). Structural investigation in solution revealed cis/trans isomeric ratios that correlate with the donor properties of the PYA ligand, with the highest cis ratios for the complex having the most donating o-PYA ligand and lowest ratios for that with the weakest donor p-PYA system. The catalytic activity of the cationic complexes [Pd(N^N′)Me(NCMe)]+ in alkene insertion and dimerization showed a strong correlation with the ligand setting. While complexes bearing more electron donating m- and o-PYA ligands produced butenes within 60 and 30 min, respectively, the p-PYA complex was much slower and only reached 50% conversion of ethylene within 2 h. Likewise, insertion of methyl acrylate as a polar monomer was more efficient with stronger donor PYA units, reaching a 32% ratio of methyl acrylate vs ethylene insertion. Mechanistic investigations about the ethylene insertion allowed detection, for the first time, by NMR spectroscopy both cis- and trans-Pd-ethyl intermediates and, furthermore, revealed a trans to cis isomerization of the Pd-ethyl resting state as the rate-limiting step for inducing ethylene conversion. These PYA palladium complexes induce rapid double-bond isomerization of terminal to internal alkenes through a chain-walking process, which prevents both polymerization and also the conversion of higher olefins, leading selectively to ethylene dimerization.
Selective Production of Terminally Unsaturated Methyl Esters from Lactones Over Metal Oxide Catalysts
Brentzel, Zachary J.,Ball, Madelyn R.,Dumesic, James A.
, p. 3072 - 3081 (2018/08/22)
Metal oxide catalysts were studied for their selectivity for the production of a terminally unsaturated methyl ester, methyl 5-hexenoate (M5H), from a 6 carbon, 6-membered ring lactone, δ-hexalactone (DHL). A 15?wt% Cs/SiO2 catalyst had a selectivity of 55% to M5H. This selectivity was the highest of the metal oxide catalysts studied, which were Cs/SiO2, MgO, SrO, CeO2, ZrO2, Ta2O5, MgAl2O4, and a Mg–Zr mixed oxide. The Cs/SiO2 catalyst was utilized for the ring-opening of γ-valerolactone (GVL), a 5 carbon, 5-membered ring lactone. The catalyst was 88% selective to the terminally unsaturated methyl ester, methyl 4-pentenoate (M4P). Weight hourly space velocity studies determined that the unsaturated ester distributions remained constant and no C=C double bond isomerization occurred. Liquid phase transesterification reactions with DHL and methanol and nuclear magnetic resonance spectroscopy confirmed that DHL undergoes ring-opening transesterification to produce an?ω-1 hydroxy methyl ester, methyl 5-hydroxyhexanoate (M5HH). Liquid phase transesterification reactions and thermochemistry calculations established that the equilibrium for GVL transesterification with methanol was favored towards the ring-closed lactone instead of the ring-opened hydroxy ester because of the decreased ring strain of GVL compared to DHL. The difference in terminally unsaturated methyl ester selectivity between GVL and DHL manifests from the difference in ring-strain energy. DHL passes through the M5HH intermediate as a result of greater ring strain, while the production of M4P from GVL most likely occurs through a direct, concerted mechanism. Graphical Abstract: [Figure not available: see fulltext.].
METHOD FOR PRODUCING PENTENOIC ACID ESTER
-
Paragraph 0041; 0042; 0043; 0048; 0051; 0052, (2019/01/19)
PROBLEM TO BE SOLVED: To provide a production method capable of obtaining a pentenoic acid ester in high yield even without using a large amount of alcohol while suppressing by-production of an ether. SOLUTION: There is provided a method for producing a pentenoic acid ester, which comprises a step of synthesizing a pentenoic acid ester containing at least one selected from the group consisting of formulas (2), (3) and (4) by bringing γ-valerolactone and an alcohol of the formula (1) into contact with each other in the presence of a catalyst containing X type zeolite. [In the formula (1), R represents an alkyl group having 1 to 6 carbon atoms. In the formulas (2), (3) and (4), R represents an alkyl group having 1 to 6 carbon atoms]. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
