scholarly journals Production of Chemoenzymatic Catalyzed Monoepoxide Biolubricant: Optimization and Physicochemical Characteristics

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Jumat Salimon ◽  
Nadia Salih ◽  
Bashar Mudhaffar Abdullah
Keyword(s):  
Linoleic Acid ◽  
Carboxylic Acid ◽  
Immobilized Lipase ◽  
Viscosity Index ◽  
Oxidative Degradation ◽  
Oxirane Oxygen ◽  
Physicochemical Characteristics ◽  
Novozym 435 ◽  
Consecutive Reactions ◽  
Acid Catalyzed

Linoleic acid (LA) is converted to per-carboxylic acid catalyzed by an immobilized lipase fromCandida antarctica(Novozym 435). This per-carboxylic acid is only intermediate and epoxidized itself in good yields and almost without consecutive reactions. Monoepoxide linoleic acid 9(12)-10(13)-monoepoxy 12(9)-octadecanoic acid (MEOA) was optimized using D-optimal design. At optimum conditions, higher yield% (82.14) and medium oxirane oxygen content (OOC) (4.91%) of MEOA were predicted at 15 μL of H2O2, 120 mg of Novozym 435, and 7 h of reaction time. In order to develop better-quality biolubricants, pour point (PP), flash point (FP), viscosity index (VI), and oxidative stability (OT) were determined for LA and MEOA. The results showed that MEOA exhibited good low-temperature behavior with PP of−41°C. FP of MEOA increased to128°Ccomparing with115°Cof LA. In a similar fashion, VI for LA was 224 generally several hundred centistokes (cSt) more viscous than MEOA 130.8. The ability of a substance to resist oxidative degradation is another important property for biolubricants. Therefore, LA and MEOA were screened to measure their OT which was observed at 189 and168°C, respectively.

scholarly journals Improvement of Physicochemical Characteristics of Monoepoxide Linoleic Acid Ring Opening for Biolubricant Base Oil

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Jumat Salimon ◽  
Nadia Salih ◽  
Bashar Mudhaffar Abdullah
Keyword(s):  
Linoleic Acid ◽  
Ring Opening ◽  
Viscosity Index ◽  
Physicochemical Characteristics ◽  
High Yield ◽  
Optimum Conditions ◽  
Base Oil ◽  
New Class ◽  
Ring Opening Reaction ◽  
Toluene Sulfonic Acid

For environmental reasons, a new class of environmentally acceptable and renewable biolubricant based on vegetable oils is available. In this study, oxirane ring opening reaction of monoepoxide linoleic acid (MEOA) was done by nucleophilic addition of oleic acid (OA) with usingp-toluene sulfonic acid (PTSA) as a catalyst for synthesis of 9(12)-hydroxy-10(13)-oleoxy-12(9)-octadecanoic acid (HYOOA) and the physicochemical properties of the resulted HYOOA are reported to be used as biolubricant base oils. Optimum conditions of the experiment using D-optimal design to obtain high yield% of HYOOA and lowest OOC% were predicted at OA/MEOA ratio of 0.30 : 1 (w/w), PTSA/MEOA ratio of 0.50 : 1 (w/w), reaction temperature at 110, and reaction time at 4.5 h. The results showed that an increase in the chain length of the midchain ester resulted in the decrease of pour point (PP) , increase of viscosity index (VI) up to 153, and improvement in oxidative stability (OT) to 180.94.

Trifluoroacetic acid catalyzed highly regioselective bromocyclization of styrene-type carboxylic acid

2016 ◽  
Vol 14 (20) ◽  
pp. 4571-4575 ◽  
Author(s):  
Tao Chen ◽  
Ying-Yeung Yeung
Keyword(s):  
Carboxylic Acid ◽  
Trifluoroacetic Acid ◽  
Acid Catalyzed

A trifluoroacetic acid catalyzed highly 6-endo regioselective bromocyclization of styrene-type carboxylic acid has been developed.

scholarly journals On the Application of Oxidative Degradation Reactions in Carboxylic Acid Synthesis.

1969 ◽  
Vol 23 ◽  
pp. 1442-1443 ◽  
Author(s):  
Nguyen Dinh-Nguyen ◽  
Aino Raal ◽  
P. H. Nielsen ◽  
P. H. Nielsen ◽  
Alf A. Lindberg ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Oxidative Degradation ◽  
Acid Synthesis ◽  
Degradation Reactions

The Theodorakis Synthesis of (–)-Jiadifenolide

2015 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Hydrogen Peroxide ◽  
Carboxylic Acid ◽  
Aldol Condensation ◽  
University Of California ◽  
Oxidative Rearrangement ◽  
Promote Neurite Outgrowth ◽  
Starting Point ◽  
Jones Reagent ◽  
Acid Catalyzed ◽  
The University

There has recently been a great deal of interest in the synthesis of natural products that promote neurite outgrowth. Emmanuel A. Theodorakis of the University of California, San Diego described (Angew. Chem. Int. Ed. 2011, 50, 3672) the preparation of one of the most potent (10 nM) of these, (–)-jiadifenolide 3. Fittingly, a key transformation en route to this highly oxygenated seco-prezizaane was the oxidative rearrangement of 1 to 2. The starting point for the synthesis was the commercially available diketone 4. Allylation followed by addition to 5 gave the prochiral triketone 6. Enantioselective aldol condensation following the Tu/Zhang protocol then delivered the bicyclic enone 7. Alkylation to give 8 proceeded with high diastereoselectivity, perhaps controlled by the steric bulk of the silyloxy group. Exposure of the protected ketone to the McMurry reagent PhNTf2 gave the enol triflate 9, which smoothly carbonylated to the lactone 10. Epoxidation with alkaline hydrogen peroxide followed by oxidation gave the carboxylic acid, which spontaneously opened the epoxide, leading to the bis lactone 1. With 1 in hand, the stage was set for the key oxidative rearrangement to 2. It was envisioned that epoxidation would generate the cis-fused 11, which on oxidation would undergo acid-catalyzed elimination to give 12. The newly freed OH would then be in position to engage the lactone carbonyl, leading to 2. In the event, oxidation of the epoxide with the Dess-Martin reagent required sonication for 2 h. The rearranged lactone, even though it was susceptible to further oxidation, was secured in 38% overall yield from 1. After hydrogenation and protection, preparation of the enol triflate 13 from the congested cyclopentanone necessitated the use of the more reactive Comins reagent. Hydrogenation of the trisubstituted alkene from coupling with Me3Al then required 90 atmospheres of H2 overpressure. Hydroxylation of the lactone 14 with the Davis oxaziridine followed by further oxidation to the ketone with the Jones reagent and deprotection then completed the synthesis of (–)-jiadifenolide 3.

scholarly journals Interesterification of Egg-Yolk Phosphatidylcholine with p-Methoxycinnamic Acid Catalyzed by Immobilized Lipase B from Candida Antarctica

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1181
Author(s):  
Magdalena Rychlicka ◽  
Anna Gliszczyńska
Keyword(s):  
Reaction Time ◽  
Design Method ◽  
Immobilized Lipase ◽  
Reaction Medium ◽  
Solvent System ◽  
Novozym 435 ◽  
Molar Ratio ◽  
Binary Solvent ◽  
Methoxycinnamic Acid ◽  
Substrate Molar Ratio

The p-methoxycinnamic acid (p-MCA) is one of the most popular phenylpropanoids, the beneficial impact of which on the human health is well documented in the literature. This compound has shown many valuable activities including anticancer, antidiabetic, and neuro- and hepatoprotective. However, its practical application is limited by its low bioavailability resulting from rapid metabolism in the human body. The latest strategy, aimed at overcoming these limitations, is based on the production of more stability in systemic circulation bioconjugates with phospholipids. Therefore, the aim of this research was to develop the biotechnological method for the synthesis of phospholipid derivatives of p-methoxycinnamic acid, which can play a role of new nutraceuticals. We developed and optimized enzymatic interesterification of phosphatidylcholine (PC) with ethyl p-methoxycinnamate (Ep-MCA). Novozym 435 and a binary solvent system of toluene/chloroform 9:1 (v/v) were found to be the effective biocatalyst and reaction medium for the synthesis of structured p-MCA phospholipids, respectively. The effects of the other reaction parameters, such as substrate molar ratio, enzyme dosage, and reaction time, on the degree of incorporation of p-MCA into PC were evaluated by use of an experimental factorial design method. The results showed that substrate molar ratio and biocatalyst load have significant effects on the synthesis of p-methoxycinnamoylated phospholipids. The optimum conditions were: Reaction time of three days, 30% (w/w) of Novozym 435, and 1/10 substrate molar ratio PC/Ep-MCA. Under these parameters, p-methoxycinnamoylated lysophosphatidylcholine (p-MCA-LPC) and p-methoxycinnamoylated phosphatidylcholine (p-MCA-PC) were obtained in isolated yields of 32% and 3% (w/w), respectively.

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