2917-73-9Relevant academic research and scientific papers
Lubricity, tribological and rheological properties of green ester oil prepared from bio-based azelaic acid
AHMED, WALED ABDO,SALIH, NADIA,SALIMON, JUMAT
, p. 1363 - 1369 (2021/06/09)
Plant oil derived compounds have been used as the raw material for the synthesis of green biolubricant. Azelaic acid derived from oleic acid is one of the interesting compounds. The synthesis of azelate esters oil based synthetic green biolubricants was carried out. The esterification process of azelaic acid with variety type of alcohols was catalyzed by concentrated H2SO4. The yields percentages of azelate esters oil produced were varied depending their overall molecular structure. The azelate esters oil properties were evaluated for their suitability as a biolubricant. The results showed that the linear azelate esters oil showed high pour point values in a range of 15 to 5°C for di-decyl azelate, di-octyl azelate and di-hexyl azelate respectively. On the other hands, the branch azelate esters oil showed very low pour point of -70, -58 and -50°C for di-2-butyloctyl azelate, di-2-ethylhexanol azelate and di-2-ethylbutyl azelate, respectively. Moreover, the linear azelate esters oil gave high values of flash point, viscosity index and oxidative stability, and they were slightly affected by branching molecule structure. The tribological and rheological properties of high molecular azelate esters oil were also performed. Subsequently, most of them were classified as non-Newtonian fluids and having boundary lubrication properties with low friction coefficient. The branch azelate esters oil is plausible to be used as green biolubricants in many applications including automotive, marine engine oils, compressor oils, hydraulic fluids, gear oils and industrial biolubricants.
Direct synthesis of adipic acid esters via palladium-catalyzed carbonylation of 1,3-dienes
Yang, Ji,Liu, Jiawang,Neumann, Helfried,Franke, Robert,Jackstell, Ralf,Beller, Matthias
, p. 1514 - 1517 (2020/01/08)
The direct carbonylation of 1,3-butadiene offers the potential for a more cost-efficient and environmentally benign route to industrially important adipic acid derivatives. However, owing to the complex reaction network of regioisomeric carbonylation and isomerization pathways, a selective practical catalyst for this process has thus far proven elusive. Here, we report the design of a pyridyl-substituted bidentate phosphine ligand (HeMaRaphos) that, upon coordination to palladium, catalyzes adipate diester formation from 1,3-butadiene, carbon monoxide, and butanol with 97% selectivity and 100% atom-economy under industrially viable and scalable conditions (turnover number > 60,000). This catalyst system also affords access to a variety of other di- and triesters from 1,2- and 1,3-dienes.
The synthesis of di-carboxylate esters using continuous flow vortex fluidics
Britton, Joshua,Dalziel, Stuart B.,Raston, Colin L.
, p. 2193 - 2200 (2016/04/19)
A vortex fluidic device (VFD) is effective in mediating the synthesis of di-esters at room temperature. Processing under ambient conditions allows for a simple and efficient synthesis, whilst operating under continuous flow addresses scalability. The rotational speed of the sample tube and the flow rate were critical variables during reaction optimization, and this relates to the behaviour of the fluid flow at a molecular level. Whilst at specific rotational speeds the tube imparts a vibrational response into the fluid flow, the flow rate dictates residence time and the ability to maintain high levels of shear stress. The combination of mechanically induced vibrations, rapid micromixing, high levels of shear stress and water evaporation results in yields up to 90% for 3.25 minutes or less residence time. These results are key for devising greener and more efficient processes both mediated by the VFD and other continuous flow platforms.
Synthesis of carboxylic acid esters in the presence of micro- and mesoporous aluminosilicates
Grigor'Eva,Suleimanova,Agliullin,Kutepov
, p. 773 - 779 (2015/01/30)
The catalytic properties of zeolites HY, HBeta, and HZSM-12 and of mesoporous amorphous aluminosilicate in liquid-phase esterification of aliphatic (monobasic C1-C18, dibasic C6, C10) and aromatic (benzoic, trimellitic, phthalic) carboxylic acids with butanol were studied. Zeolite HBeta appeared to be the most active catalyst. Procedures were developed for preparing esters in the presence of zeolitic catalyst HBeta, ensuring 100% selectivity of ester formation at 90-98% conversion of the acid.
SELECTIVE MONOETHERIFICATION AND MONOESTERIFICATION OF DIOLS AND DIACIDS UNDER PHASE-TRANSFER CONDITIONS
Zerda, Jaime de la,Barak, Gabriela,Sasson, Yoel
, p. 1533 - 1536 (2007/10/02)
Research on the selectivity of etherification reactions of diols and esterification reactions of diacids by alkyl halides under phase-transfer catalysis has shown that under such conditions, selectivity of monoetherification increases in the order prim sec tert diols, though overall yield of monoether decreases from sec to tert diols.Monoesterification of diacids was accomplished with a high degree of selectivity.Optimal extraction of diols and diacids was found to correspond in general to chain lengths of around 5 carbons.This could mean that the complex formed between the catalyst and the anion to react is stabilized for certain carbon lengths by inner solvation in virtue of its spatial conformation.
