7425-14-1Relevant articles and documents
Study the Efficiency of Some Esters Based on 2- Ethyl Hexanoic Acid as Synthetic Lubricants
Kamal, Rasha S.,Nassar, Amal M.,Ahmed, Nehal S.
, p. 7191 - 7200 (2021/11/16)
Esters have many important properties, such as biodegradation, low toxicity, good thermal stability and excellent solvability, because these features are definitely the most versatile of the various types of base fluids currently available and can be modified to provide unique physical and chemical properties that can be designed to meet the lubricant industry's challenges. In this article, Reaction was prepared by various branched synthetic esters of 2- ethyl hexanoic acid with different 2 groups of alcohols, the first one (1-hexanol, 2- ethyl hexanol,1-octanol, 1- dodecanol and 1- hexadecanol), and the second group (neopentyl glycol, trimethylol propane and pentaerythritol). All the preparation compound form were confirmed by examine the physical and chemical properties as (Nuclear Magnetic Resonance, Infra-Red Spectroscopy, Total Acid Number, Density, Thermo Gravimetric Analysis TGA, Specific gravity, Reflective index, Molecular weights estimation and flash point). As a synthetic lubricating oil, the performance of these compounds was studied. Prepared compounds have been found to contain low pour point (PP), high viscosity level (VI) and Newtonian fluid for rheological behavior.
Practical catalytic nitration directly with commercial nitric acid for the preparation of aliphatic nitroesters
An, Jichao,He, Pan,Li, Wenhao,Liu, Peipei,Si, Mengyuan,Yang, Bo,Yang, Guanyu
, p. 6612 - 6616 (2020/09/21)
To pursue a sustainable and efficient approach for aliphatic nitroester preparation from alcohol, europium-triflate-catalyzed nitration, which directly uses commercial nitric acid, has been successfully developed. Gram scalability with operational ease showed its practicability.
Process for the production of esters
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Page/Page column 2; 3, (2020/03/18)
A process for making methyl esters in high yields. The process comprises contacting aliphatic or aromatic aldehydes and methanol with a homogeneous dimeric ruthenium catalyst, to catalyze the dehydrogenative coupling between aliphatic or aromatic aldehydes and methanol. The reaction is highly selective (99.9%) toward the formation of methyl esters over homoesters and alcohols and operates at temperatures of less than 100° C. for 2-8 hours.
Iron-catalyzed selective production of methyl esters from aldehydes
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Page/Page column 2-3, (2020/04/01)
A process for making methyl esters in high yields is provided. The process comprises contacting aliphatic or aromatic aldehydes and methanol with an iron catalyst, to catalyze the dehydrogenative coupling between aliphatic or aromatic aldehydes and methanol. The reaction is highly selective (99.9%) toward the formation of methyl esters over homoesters and alcohols and operates at temperatures of less than 100° C. for 2-8 hours.
Manganese Pincer Complexes for the Base-Free, Acceptorless Dehydrogenative Coupling of Alcohols to Esters: Development, Scope, and Understanding
Nguyen, Duc Hanh,Trivelli, Xavier,Capet, Frédéric,Paul, Jean-Fran?ois,Dumeignil, Franck,Gauvin, Régis M.
, p. 2022 - 2032 (2017/08/14)
Aliphatic PNP pincer-supported earth-abundant manganese(I) dicarbonyl complexes behave as effective catalysts for the acceptorless dehydrogenative coupling of a wide range of alcohols to esters under base-free conditions. The reaction proceeds under neat conditions, with modest catalyst loading and releasing only H2 as byproduct. Mechanistic aspects were addressed by synthesizing key species related to the catalytic cycle (characterized by X-ray structure determination, multinuclear (1H, 13C, 31P, 15N, 55Mn) NMR, infrared spectroscopy, inter alia), by studying elementary steps connected to the postulated mechanism, and by resorting to DFT calculations. As in the case of related ruthenium and iron PNP catalysts, the dehydrogenation results from cycling between the amido and amino-hydride forms of the PNP-Mn(CO)2 scaffold. For the dehydrogenation of alcohols into aldehydes, our results suggest that the highest energy barrier corresponds to the hydrogen release from the amino-hydride form, although its value is close to that of the outer-sphere dehydrogenation of the alcohol into aldehyde. This contrasts with the ruthenium and iron catalytic systems, where dehydrogenation of the substrate into aldehyde is less energy-demanding compared to hydrogen release from the cooperative metal-ligand framework.
Acceptorless dehydrogenative coupling of alcohols catalysed by ruthenium PNP complexes: Influence of catalyst structure and of hydrogen mass transfer
Zhang, Lei,Raffa, Guillaume,Nguyen, Duc Hanh,Swesi, Youssef,Corbel-Demailly, Louis,Capet, Frédéric,Trivelli, Xavier,Desset, Simon,Paul, Sébastien,Paul, Jean-Fran?ois,Fongarland, Pascal,Dumeignil, Franck,Gauvin, Régis M.
, p. 331 - 343 (2016/07/06)
Base-free catalytic acceptorless dehydrogenative homo-coupling of alcohols to esters under neat conditions was investigated using a combined organometallic synthesis and kinetic modelling approach. The considered bifunctional ruthenium aliphatic PNP complexes are very active, affording TONs up to 15,000. Notably, gas mass transfer issues were identified, which allowed us to rationalize previous observations. Indeed, the reaction kinetics are limited by the rate of transfer from the liquid phase to the gas phase of the hydrogen co-produced in the reaction. Mechanistically speaking, this relates to the interconverting couple amido monohydride/amino bishydride. Overcoming this by switching into the chemical regime leads to an initial turnover frequency increase from about 2000 up to 6100?h?1. This has a significant impact when considering assessment of novel or reported catalytic systems in this type of reaction, as overlooking of these engineering aspects can be misleading.
Efficient and simple approaches towards direct oxidative esterification of alcohols
Ray, Ritwika,Jana, Rahul Dev,Bhadra, Mayukh,Maiti, Debabrata,Lahiri, Goutam Kumar
supporting information, p. 15618 - 15624 (2016/02/18)
The present article describes novel oxidative protocols for direct esterification of alcohols. The protocols involve successful demonstrations of both "cross" and "self" esterification of a wide variety of alcohols. The cross-esterification proceeds under a simple transition-metal-free condition, containing catalytic amounts of TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy)/TBAB (tetra-n-butylammonium bromide) in combination with oxone (potassium peroxo monosulfate) as the oxidant, whereas the self-esterification is achieved through simple induction of Fe(OAc)2/dipic (dipic=2,6-pyridinedicarboxylic acid) as the active catalyst under an identical oxidizing environment. One-pot oxidative esterification: A wide variety of alcohols undergo transition-metal-free (in the presence of oxone/2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)/tetra-n-butylammonium bromide (TBAB)) selective "cross" esterification in moderate to excellent yields (see Figure). The "self" esterification process has however been achieved in the presence of Fe(OAc)2/2,6-pyridinedicarboxylic acid (dipic) as the active catalytic species under a similar oxidizing environment.
Efficient dimeric esterification of alcohols with NBS in water using l-proline as catalyst
Liu, Xiuhong,Wu, Jun,Shang, Zhicai
experimental part, p. 75 - 83 (2011/11/05)
The L-proline-catalyzed oxidation of aliphatic primary alcohols with N-bromosuccimide (NBS) in water at room temperature to afford the corresponding dimeric esters in good to excellent yields was described. This pathway of dimeric esterification was proved to be very simple and environmentally friendly.
Dehydrogenative coupling of primary alcohols to form esters catalyzed by a ruthenium N-heterocyclic carbene complex
Solvhoj, Amanda,Madsen, Robert
experimental part, p. 6044 - 6048 (2012/01/13)
The ruthenium complex [RuCl2(IiPr)(p-cymene)] catalyzes the direct condensation of primary alcohols into esters and lactones with the release of hydrogen gas. The reaction is most effective with linear aliphatic alcohols and 1,4-diols and is believed to proceed with a ruthenium dihydride as the catalytically active species.
Selective oxidation of primary alkanols into the "symmetrical" esters with the H2O2-MBr-HCl system
Nikishin,Sokova,Kapustina
experimental part, p. 310 - 312 (2011/11/05)
Oxidation of linear or branched primary alkanols with H2O 2-MBr (M = Li, Na, K)-HCl system in water affords the corresponding "symmetrical" esters in almost quantitative yield.
