109-94-4Relevant articles and documents
Merger of Johnson-Claisen rearrangement and alkoxycarbonylation for atom efficient diester synthesis
Seidensticker, Thomas,M?ller, David,Vorholt, Andreas J.
, p. 371 - 374 (2016)
The orthoester Johnson-Claisen rearrangement of allyl alcohol with triethyl orthoacetate for the synthesis of ethyl 4-pentenoate has been optimized, in order to allow for a selective and efficient subsequent alkoxycarbonylation using formates in an atom efficient manner. Diethyl adipate was successfully yielded in up to 89% applying very low orthoester excess, formic acid and mild reaction conditions in an innovative, one-pot procedure.
A short high yielding synthesis of the potent anti-VZV carbocyclic nucleoside analogue carba-BVDU
Wyatt,Anslow,Coomber,Cousins,Evans,Gilbert,Humber,Paternoster,Sollis,Tapolczay,Weingarten
, p. 2039 - 2049 (1995)
A short high yielding synthesis of the potent anti-varicella-zoster virus (VZV) carbocyclic nucleoside analogue carba-BVDU 1 starting from aminodiol 2 is described. Reaction of 2 with acyl carbamate 3 and subsequent ring closure under acidic conditions afforded 5-ethyl-2'-deoxy-4'a-carbauridine 5. In situ acetylation of 5 afforded 3',5'-di-O-acetyl-5-ethyl-2'-deoxy-4'a-carbauridine 6 in 78% overall yield from 2. Radical bromination of 6 with either bromine or NBS and subsequent treatment with triethylamine gave an efficient conversion to 3',5'-di-O-acetyl-5-(E)-(2-bromovinyl)-2'-deoxy-4'a- carbauridine 7. Deacetylation of 7 afforded 1 in an overall 45-53% yield from 2.
Formic acid directly assisted solid-state synthesis of metallic catalysts without further reduction: As-prepared Cu/ZnO catalysts for low-temperature methanol synthesis
Shi, Lei,Shen, Wenzhong,Yang, Guohui,Fan, Xiaojing,Jin, Yuzhou,Zeng, Chunyang,Matsuda, Kenji,Tsubaki, Noritatsu
, p. 83 - 90 (2013)
Metallic catalysts (Cu/ZnO) and pure metals (Co, Ni, and Ag) without any impurities are directly prepared by a novel formic acid-assisted solid-state method without further reduction. During the decomposition of metal-formic acid precursors at 523 K under argon, H2 and CO are liberated and act in situ as reducing agents to obtain pure metals and metallic catalysts (C argon). X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive spectroscopy, and temperature-programmed reduction analysis reveal that the as-prepared catalyst Cargon without further reduction is converted into metallic Cu0 and ZnO species. TPR analysis results, Fourier transform infrared analysis, and the thermal decomposition behavior in air illustrate that no amorphous carbon or carbonic residues are left in Cargon when formic acid is used as the chelating agent and reductant, because formic acid is the simplest organic acid. The as-prepared Cu/ZnO catalyst is tested for low-temperature methanol synthesis at 443 K from syngas containing CO2 and using ethanol as a solvent and catalyst; it exhibits much higher activity and methanol selectivity than catalysts prepared by conventional solid-state methods.
Etherification of biomass-derived furanyl alcohols with aliphatic alcohols over silica-supported nickel phosphide catalysts: Effect of surplus P species on the acidity
Kim, Jinsung,Shin, Mi,Suh, Young-Woong
, (2020)
The acidity of nickel phosphide (Ni2P) catalysts plays a crucial role in producing a desired hydrodeoxygenation molecule from biomass-derived substrates; yet, it has never been explored in acid-catalyzed reactions. Herein, we demonstrated the activity of silica-supported Ni2P catalyst prepared with the nominal P/Ni ratio of 2 (Ni2P/SiO2-2P) in the etherification of furanyl alcohols (particularly, 5-(hydroxymethyl)furfural) with aliphatic alcohols including ethanol. By comparing the characteristics of Ni/SiO2, PxOy/SiO2, and Ni2P/SiO2-xP (x = 0.5 and 1), Ni2P/SiO2-2P was revealed to contain the Br?nsted and Lewis acid sites of which both contributed to the etherification reaction. Notably, the Br?nsted acidity was associated with the surplus P species added to produce the Ni2P phase. Consequently, supported Ni2P catalysts can work in acid-catalyzed reactions if an adequate ratio of Br?nsted to Lewis acid sites is provided by the amount of the surplus P species determined by adjusting the P/Ni ratio.
The products of the reaction of the hydroxyl radical with 2-ethoxyethyl acetate
Wells,Wiseman, Floyd L.,Williams, Dale C.,Baxley, J. Steven,Smith
, p. 475 - 480 (1996)
The gas-phase reaction products of the OH radical with 2-ethoxyethyl acetate (EEA, CH3C(O)OCH2CH2OCH2CH3) have been investigated. 1,2-Ethanediol acetate formate (EAF, CH3C(O)OCH2CH2OC(O)H)and ethyl formate (EF, HC(O)OCH2CH3) were identified as the two main products. A third product, ethylene glycol diacetate (EGD, CH3C(O)OCH2CH2OC(O)CH3), was also observed. EAF, EF, and EGD formation yields were determined to be 0.37 ±0.03 and 0.328 ± 0.018 and 0.040 ± 0.005. respectively. Proposed reaction mechanisms are discussed and compared with these data. 1996 John Wiley & Sons, inc.
Ru catalyzed hydrogenation of CO2 to formate under basic and acidic conditions
Cannon, Austin T.,Saouma, Caroline T.
, (2021)
The hydrogenation of CO2 to MeOH is pertinent to advance future energy schemes. Towards this end, phosophine-ligated Ru catalysts have been shown to achieve this transformation under either acidic or basic conditions. In this manuscript, we screen catalytic conditions for a novel tris(phosphine) ligand with Ru to see if it can facilitate the conversion of CO2 to MeOH under both acidic and basic conditions. With both sets of conditions, we observe hydrogenation of CO2 to formate. This work shows that the same catalytic system can function under both reaction types but is limited to formate production.
The hydroxyl radical reaction rate constant and products of ethyl 3-ethoxypropionate
Steven Baxley,Henley, Michael V.,Wells
, p. 637 - 644 (1997)
The relative rate technique has been used to measure the hydroxyl radical (OH) reaction rate constant of ethyl 3-ethoxypropionate (EEP, CH3CH2-O-CH2CH2C(O)O-CH 2CH3). EEP reacts with OH with a bimolecular rate constant of (22.9 ± 7.4) × 10-12 cm3 molecule-1 s-1 at 297 ± 3 K and l atmosphere total pressure. In order to more clearly define EEP's atmospheric reaction mechanism, an investigation into the OH + EEP reaction products was also conducted. The OH + EEP reaction products and yields observed were: ethyl glyoxate (EG, 25 ± 1% HC(=O)C(=O)-O-CH2CH3), ethyl (2-formyl) acetate (EFA, 4.8 ± 0.2%, HC(=O)-CH2-C(=O)-O-CH2CH3), ethyl (3-formyloxy) propionate (EFP, 30 ± 1%, HC(=O)-O-CH2CH2-C(=O)-O-CH2CH3), ethyl formate (EF, 37 ± 1%, HC(=O)O-CH2CH3), and acetaldehyde (4.9 ± 0.2%, HC(=O)CH3). Neither the EEP's OH rate constant nor the OH/EEP reaction products have been previously reported. The products' formation pathways are discussed in light of current understanding of oxygenated hydrocarbon atmospheric chemistry.
Synthesis, characterization, and catalytic application of a cationic metal-organic framework: Ag2(4,4′-bipy)2(O 3SCH2CH2so3)
Fei, Honghan,Paw U, Latisha,Rogow, David L.,Bresler, Marc R.,Abdollahian, Yashar A.,Oliver, Scott R. J.
, p. 2027 - 2032 (2010)
We report a silver-based cationic metal-organic framework with two mixed organic linkers directing the structure. The structure consists of ID Ag(4,4′-bipy) cationic chains arranged into closepacked layers. Weakly bound alkanedisulfonate anions charge-balance the layers, where only one oxygen of each sulfonate makes a long contact with the Ag. The unsaturated linear Ag centers likely allow the Lewis acidity displayed by the material for ketone protection as well as esterification. The material showed no reduction in yield after three catalytic runs with average 95% conversion yield for ketal formation and 57% for esterification without further water removal. In addition to hydrothermal conditions, the structure can be synthesized by reflux or room temperature, with almost identical catalytic ability. Other properties of this compound including chemical and thermal stability are also described.
The Reaction of Alkoxides with Dicobalt Octacarbonyl: Trapping of the Co(I) Intermediate in the Disproportionation ( Base Reaction ) with a Hard Lewis Base
Tasi, Miklos,Sisak, Attila,Ungvary, Ferenc,Palyi, Gyula
, p. 1103 - 1106 (1985)
Dicobalt octacarbonyl reacts with alcoholates (RO(-)) yielding alkoxycarbonylcobalt tetracarbonyls, ROC(O)Co(CO)4. - (Keywords: Alkoxides, reaction with dicobalt octacarbonyl; Alkoxycarbonylcobalt tetracarbonyls; Hydrocarbalkoxylation intermediates)
Hydrolysis of Imidazole-Containing Amide Acetals
Brown, R. S.,Ulan, J. G.
, p. 2382 - 2388 (1983)
N-(Dialkoxymethyl)imidazoles (amide acetals 1a-c) are shown to hydrolyze by a common mechanism between pH 1 and pH 11 that involves preequilibrium protonation of the imidazole distal N, followed by rate-llimiting C - N cleavage.The Broensted plot of the log C - N cleavage rate vs. pKa of the parent imidazole has a slope of -1.0 and suggest a transition sate in which (+) is nearly completely transferred to the departing dialkoxymethyl group.Throughout the pH range studied, C - N cleavage is the dominant process.The bicyclic amide acetal 2 formed from 4(5)-(hydroxyethyl)imidazole and triethyl orthoformate behaves similarly to the acyclic cases at pHs > 5 except that the observed rate of C - N cleavage for the former is depressed by (1 - 2) x 102-fold.This apparent reduction of C - N cleavage rate is analyzed in terms of reversibility of the ring opening.Such reversal is demonstrated by the ability of good nucleophiles such as N3- or H2NOH to trap the open ion, preventing reversal and hence increasing the apparent rate of loss of 2.From pH 0 to pH 5, an additional sigmoidal event in the pH/log kobsd profile for 2 is observed, which is analyzed as a protonation of the imidazole of the open ion.Such a protonation prevents the reversible reclosure and concomitantly increases the kobsd.Bicyclic 2 can be taken as a model for the tetrahedral intermediate formed during intramolecular alcoholysis of an N-acylimidazole or intramolecular attack of an imidazole on an ester.
