scholarly journals Dialkyl Succinates and Adipates as Alternative Plasticizers—Even More Efficient Synthesis

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6219
Author(s):  
Natalia Barteczko ◽  
Justyna Więcławik ◽  
Anna Tracz ◽  
Ewa Pankalla ◽  
Karol Erfurt ◽  
...  
Keyword(s):  
Simple Procedure ◽  
Product Formation ◽  
Liquid System ◽  
Industrial Applications ◽  
Molar Ratio ◽  
High Yield ◽  
Reaction Conditions ◽  
Two Phase ◽  
Phase Liquid ◽  
High Yields

As a result of strict regulations of phthalate plasticizers, alternative non-phthalate forms are desired and increasingly used. This work presents a synthetic method for alternative plasticizers (dialkyl succinates and adipates) via esterification of succinic and adipic acid with alcohols: butan-1-ol and 2-ethylhexan-1-ol. Ionic liquids were synthesized by the reaction of triethylamine with over-equimolar (1:2.7) amounts of sulfuric(VI) acid, which were used as an acidic catalyst and solvent. The two-phase liquid–liquid system was formed during the reaction due to immiscibility of the esters with the ionic liquid. This phenomenon is a driving force of this process, shifting the equilibrium toward the product formation. As a result, dialkyl succinates and adipates were obtained in high yields (99%) and selectivities (>99%), under mild reaction conditions at 70–80 °C and using a 4:1 molar ratio of alcohol to acid and 15 mol% of catalyst. The catalyst was recycled 10 times without any loss of activity. This alternative method is highly competitive: it involves a simple procedure for product isolation as well as a high yield and purity of the resulting esters. These advantages make this method sustainable and promising for industrial applications.

Two-Phase Beckmann Rearrangement of Cyclohexanone Oxime under Milder Conditions in Cyclohexane

2013 ◽  
Vol 634-638 ◽  
pp. 145-151
Author(s):  
Guo Qing Liu ◽  
Jian Wu ◽  
He An Luo
Keyword(s):  
Beckmann Rearrangement ◽  
Molar Ratio ◽  
High Yield ◽  
Cyclohexanone Oxime ◽  
Reaction Conditions ◽  
Two Phase ◽  
Conventional Technology ◽  
Phase Liquid ◽  
D Value

An innovative green process of producing ε-caprolactam (CPL) was proposed by integrating ammoximation and Beckmann rearrangement effectively. As a second part of the new process, two-phase (liquid-liquid) Beckmann rearrangement of cyclohexanone oxime to caprolactam was carried out using solution of oxime-cyclohexane as reactant instead of melting oxime in conventional route. The experimental results indicated that a relatively high yield of CPL can be achieved with much less oleum under milder reaction conditions in comparison with conventional technology. Furthermore, preliminary work on the quality of CPL, characterized by D value, was also performed. It was found that molar ratio of acid to oxime had a great impact on D value while the influences of other parameters were less important.

scholarly journals Promising Immobilization of Industrial-Class Phospholipase A1 to Attain High-Yield Phospholipids Hydrolysis and Repeated Use with Optimal Water Content in Water-in-Oil Microemulsion Phase

2021 ◽  
Vol 11 (4) ◽  
pp. 1456
Author(s):  
Yusuke Hayakawa ◽  
Ryoichi Nakayama ◽  
Norikazu Namiki ◽  
Masanao Imai
Keyword(s):  
Water Content ◽  
Reaction Rate ◽  
Enzyme Reaction ◽  
Initial Reaction Rate ◽  
Industrial Applications ◽  
Molar Ratio ◽  
High Yield ◽  
Initial Reaction ◽  
Phospholipase A1 ◽  
Repeated Use

In this study, we maximized the reactivity of phospholipids hydrolysis with immobilized industrial-class phospholipase A1 (PLA1) at the desired water content in the water-in-oil (W/O) microemulsion phase. The optimal hydrophobic-hydrophilic condition of the reaction media in a hydrophobic enzyme reaction is critical to realize the maximum yields of enzyme activity of phospholipase A1. It was attributed to enzymes disliking hydrophobic surroundings as a special molecular structure for reactivity. Immobilization of PLA1 was successfully achieved with the aid of a hydrophobic carrier (Accurel MP100) combination with the treatment using glutaraldehyde. The immobilized yield was over 90% based on simple adsorption. The hydrolysis reaction was kinetically investigated through the effect of glutaraldehyde treatment of carrier and water content in the W/O microemulsion phase. The initial reaction rate increased linearly with an increasing glutaraldehyde concentration and then leveled off over a 6% glutaraldehyde concentration. The initial reaction rate, which was predominantly driven by the water content in the organic phase, changed according to a typical bell-shaped curve with respect to the molar ratio of water to phospholipid. It behaved in a similar way with different glutaraldehyde concentrations. After 10 cycles of repeated use, the reactivity was well sustained at 40% of the initial reaction rate and the creation of the final product. Accumulated yield after 10 times repetition was sufficient for industrial applications. Immobilized PLA1 has demonstrated potential as a biocatalyst for the production of phospholipid biochemicals.

scholarly journals Collisions of Two-Phase Liquid Droplets in a Heated Gas Medium

Entropy ◽  
2021 ◽  
Vol 23 (11) ◽  
pp. 1476
Author(s):  
Pavel Tkachenko ◽  
Nikita Shlegel ◽  
Pavel Strizhak
Keyword(s):  
Volume Fraction ◽  
Industrial Applications ◽  
Droplet Breakup ◽  
Liquid Volume ◽  
Liquid Droplets ◽  
Vapor Bubbles ◽  
Two Phase ◽  
Relative Volume Fraction ◽  
Phase Liquid ◽  
Gas Medium

The paper presents the experimental research findings for the integral characteristics of processes developing when two-phase liquid droplets collide in a heated gas medium. The experiments were conducted in a closed heat exchange chamber space filled with air. The gas medium was heated to 400–500 °C by an induction system. In the experiments, the size of initial droplets, their velocities and impact angles were varied in the ranges typical of industrial applications. The main varied parameter was the percentage of vapor (volume of bubbles) in the droplet (up to 90% of the liquid volume). The droplet collision regimes (coalescence, bounce, breakup, disruption), size and number of secondary fragments, as well as the relative volume fraction of vapor bubbles in them were recorded. Differences in the collision regimes and in the distribution of secondary fragments by size were identified. The areas of liquid surface before and after the initial droplet breakup were determined. Conditions were outlined in which vapor bubbles had a significant and, on the contrary, fairly weak effect on the interaction regimes of two-phase droplets.

scholarly journals A Method for Solubility Measurements in a Two Phase Liquid System.

1971 ◽  
Vol 25 ◽  
pp. 3543-3544
Author(s):  
Lars-Ingvar Staffansson ◽  
D. G. Nicholson ◽  
Bjarne Kimland ◽  
Curt R. Enzell ◽  
R. J. J. C. Lousberg ◽  
...  
Keyword(s):  
Liquid System ◽  
Two Phase ◽  
Phase Liquid

Synthesis of thiol-derivatised gold nanoparticles in a two-phase Liquid–Liquid system

1994 ◽  
Vol 0 (7) ◽  
pp. 801-802 ◽  
Author(s):  
Mathias Brust ◽  
Merryl Walker ◽  
Donald Bethell ◽  
David J. Schiffrin ◽  
Robin Whyman
Keyword(s):  
Gold Nanoparticles ◽  
Liquid System ◽  
Two Phase ◽  
Phase Liquid

scholarly journals Full N,N-Methylation of 4,4′-Methylenedianiline with Dimethyl Carbonate: A Feasible Access to 4,4′-Methylene bis(N,N-Dimethylaniline)

2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Zegang Qiu ◽  
Kunjie Wang ◽  
Zhiqin Li ◽  
Tao Li ◽  
Jinhao Bai ◽  
...  
Keyword(s):  
Zinc Acetate ◽  
Dimethyl Carbonate ◽  
Reaction Pathway ◽  
Major Product ◽  
High Yield ◽  
Synthetic Route ◽  
Reaction Conditions ◽  
High Yields ◽  
By Products

The full N,N-methylation of 4,4′-methylenedianiline (MDA) with dimethyl carbonate (DMC) was investigated. The yield of the major product 4,4′-methylene bis(N,N-dimethylaniline) (MBDMA) reached as high as 97% over NaY catalyst at 190°C for 6 h. The catalyst could be used for two more times with acceptable MBDMA yields higher than 90%. The main by-products were identified as three N-methylated derivatives. Surprisingly, the formation of the N-methoxycarbonylation product was extremely restrained, which could be produced in high yields of 98% on zinc acetate catalyst. Furthermore, the reaction pathway to the major product MBDMA was proposed. Finally, a feasible synthetic route of 4,4′-methylene bis(N,N-dimethylaniline) (MBDMA) was established, featuring a high yield, mild reaction conditions, and simple operations.

scholarly journals One-pot, three-component synthesis of pyrrolo[2,3-d]pyrimidine derivatives

2018 ◽  
Vol 62 (1) ◽  
Author(s):  
Jabbar Khalafy ◽  
Ramin Javahershenas
Keyword(s):  
Simple Procedure ◽  
Reaction Times ◽  
Pyrimidine Derivatives ◽  
Reaction Conditions ◽  
One Pot ◽  
General Applicability ◽  
Green Approach ◽  
Three Component Reaction ◽  
High Yields ◽  
Work Up

<p>A green approach for the synthesis of polyfunctionalized pyrrolo[2,3-<em>d</em>]pyrimidine derivatives was successfully achieved by a one-pot, three-component reaction of arylglyoxals, 6-amino-1,3-dimethyluracil and barbituric acid derivatives in the presence of tetra-<em>n</em>-butylammonium bromide (TBAB) (5 mol%) as the catalyst in ethanol at 50 °C. This protocol has many advantages such as high yields (73-95%), green and simple procedure, short reaction times, easy work-up, mild reaction conditions and general applicability.</p>

Chiral Phosphine Ligands in the Structural Chemistry of Gold

1997 ◽  
Vol 52 (12) ◽  
pp. 1477-1483 ◽  
Author(s):  
Angela Bayler ◽  
Andreas Bauer ◽  
Hubert Schmidbaur
Keyword(s):  
Silver Chloride ◽  
Variable Temperature ◽  
Phosphine Ligands ◽  
Hydroxyl Group ◽  
Molar Ratio ◽  
Racemic Mixture ◽  
Nmr Studies ◽  
Two Phase ◽  
Ambient Temperatures ◽  
High Yields

Abstract The reaction of chloro(dimethylsulfide)gold(I) with (2-hydroxybutyl)diphenylphosphine (L) (racemic mixture) in dichloromethane affords high yields of the racemic chiral complex (L)AuCl. Metathesis reactions with KBr or KI, respectively, in a two-phase solvent mix­ ture (CH2CI2/H2O) lead to a conversion into the corresponding bromide and iodide complexes (L)AuBr and (L)AuI. Treatment of silver chloride with the ligand L in acetonitrile yields the analogous 1:1 adduct (L)AgCl. The compounds have been characterized by their analytical and spectroscopic data, and the structures of (L)AuCl and (L)AuBr have been determined by single-crystal X-ray diffraction. The compounds build isomorphous crystal lattices (monoclinic, P21/c) in which pairs of enantiomers (R-and S-configuration of L) are aggregated by two long hydrogen bonds between the hydroxyl group of the ligand and the halogen substituent of the neighbouring molecule. Cationic, linear two-coordinate 1:2 complexes (L)2Au+ X-(X = BF4, CIO4, SO3CF3) and (L)2Ag+ X-(X = BF4) are obtained in good yields by reaction of L with Me2SAuCl and AgX (molar ratio 2:1:1) or with AgBF4 (molar ratio 2:1), respectively. 31P NMR studies at variable temperature show an equilibrium between all possible stereoisomers (RR, SS, RS, SR) in solution with rapid ligand exchange at ambient temperatures.

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