Nanofiltration of rhodium tris(triphenylphosphine) catalyst in ethyl acetate solution

2012 ◽  
Author(s):  
Maizatul S. Shaharun ◽  
Ahmad K. Mustafa ◽  
Mohd F. Taha
Keyword(s):  
Ethyl Acetate ◽  
Acetate Solution ◽  
Ethyl Acetate Solution

scholarly journals Preparation and Photochromic Performance of Homogeneous Phase Nitrocellulose Membrane Grafting Spirooxazine Moieties

Coatings ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 569
Author(s):  
Bin-Bin Sun ◽  
Bing-Hua Yao ◽  
Yang-Qing He ◽  
Bo Yang
Keyword(s):  
Ethyl Acetate ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Colored Form ◽  
Isobutyl Ketone ◽  
Photochromic Properties ◽  
Photochromic Behavior ◽  
Reaction Rate Constants ◽  
13C Nuclear Magnetic Resonance ◽  
Relative Absorption

The synthesis of 1,3,3-trimethyl-9′-acryloxyspiro[indoline-2,3′(3H)naphtho[2,1-b][l,4]-oxazine] (AISO) was carried out by catalytic esterification of 1,3,3-trimethyl-9′-hydroxyspiro-[indoline-2,3′(3H)naphtho[2,1-b][l,4]oxazine] (SO–OH) and acrylic acid in the presence of 1,3-dicyclohexylcarbodiimide (DCC) and N-dimethylaminopyridine (DMAP). Then, the synthesis of the target copolymer (NC-g-AISO) was was carried out by benzoyl peroxide (BPO)-induced graft copolymerization of the AISO monomer onto nitrocellulose (NC) in a homogeneous methyl isobutyl ketone medium. The structure of NC-g-AISO was characterized by Fourier transform infrared (IR) spectroscopy, 13C Nuclear Magnetic Resonance (NMR) spectra and thermogravimetric (TG) analysis. The photochromic properties of NC-g-AISO were investigated by examining UV–Vis spectra in ethyl acetate solution and solid membrane. Compared with the AISO monomer in ethyl acetate solution, the thermal color decay stability of the colored form of NC-g-AISO in ethyl acetate solution and in solid membrane improved significantly. The thermal color decay reaction rate constants in ethyl acetate solution and membrane at 25 °C were 1.77 × 10–2 and 1.36 × 10–3 s–1, respectively, fitted using the first-order reaction equation. After ten photochromic cycles, the relative absorption intensity of the colored form of NC-g-AISO decreased by 0.85%, indicating that the NC-g-AISO membrane has good reversible photochromic behavior.

Spectrophotometric Determination of Capsaicin

1977 ◽  
Vol 60 (4) ◽  
pp. 970-972 ◽  
Author(s):  
José Jorge Ramos Palacio
Keyword(s):  
Ethyl Acetate ◽  
Rapid Method ◽  
Spectrophotometric Determination ◽  
Acetate Solution ◽  
Ethyl Acetate Solution

Abstract A rapid method has been developed for determining the pungency of hot paprika. Paprika is extracted with ethyl acetate, and an ethyl acetate solution of vanadium oxytrichloride is added just before reading at 720 nm. The method is sensitive for small quantities, i.e., less than 0.05%, and it is not necessary to isolate and purify the capsaicin.

scholarly journals 4,5-Dichloro-3H-1,2-dithiol-3-one

IUCrData ◽  
2016 ◽  
Vol 1 (11) ◽  
Author(s):  
Khaled Boukebbous ◽  
El Adoui Laifa ◽  
Aimery De Mallmann ◽  
Mostafa Taoufik
Keyword(s):  
Ethyl Acetate ◽  
Carbonyl Group ◽  
Torsion Angle ◽  
Title Compound ◽  
Expected Value ◽  
Planar Geometry ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Monoclinic System ◽  
Bond Lengths

The crystallization from an ethyl acetate solution of the title compound, also known as dichloro-1,2-dithiacyclopentenone, C3Cl2OS2, leads to a monoclinic system withP21/nspace group. The molecule displays an almost planar geometry, with a torsion angle of −2.1 (1)° for the endocyclic C—C—S—S fragment. The S—S and C=O bond lengths are 2.0521 (8) and 1.212 (3) Å, respectively. The endocyclic S—C—C angle sustained by the carbonyl group, 110.94 (16)°, deviates from the expected value of 120° for ansp2-hybridized C atom. In the crystal, short S...S, S...Cl, S...O and Cl...Cl contacts are observed.

An Efficient Synthesis of Highly Substituted Spiro[Fluorene-9,3′-[1,2,4]Triazoles from the Reaction of N3-Substituted Amidrazones with (2,4,7-Trinitro-9H-Fluoren-9-Ylidene)Propanedinitrile

2018 ◽  
Vol 42 (3) ◽  
pp. 138-140 ◽  
Author(s):  
Mohsen A.-M. Gomaa ◽  
Huda A. Ali
Keyword(s):  
Ethyl Acetate ◽  
Ambient Temperature ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Efficient Synthesis

Novel spiro[fluorene-9,3′-[1,2,4]triazoles were obtained in excellent yields from the reaction of N3-substituted benzamidrazones and (2,4,7-trinitro-9 H-fluoren- 9-ylidene)propanedinitrile in ethyl acetate solution at ambient temperature. The react ion mechanism is discussed.

Synthesis and Application of New Carboxyl Modified Silicone Oil

2013 ◽  
Vol 631-632 ◽  
pp. 437-441
Author(s):  
Ning Lei ◽  
Qiu Feng An ◽  
Jiao Jiao Ning
Keyword(s):  
Maleic Anhydride ◽  
Ethyl Acetate ◽  
Silicone Oil ◽  
Raw Materials ◽  
Water Repellency ◽  
Acetate Solution ◽  
Ethyl Acetate Solution ◽  
Finishing Agent

A kind of new carboxyl and vinyl co-modified silicone oil (Vi-CAS-1) was synthesized with vinyl/amino co-modified silicone oil (Vi-ASO-1) and maleic anhydride (MA) as raw materials. Then 0.03 % Vi-CAS-1 in ethyl acetate solution was used as a finishing agent, the performance of Vi-CAS-1 on dacron fabrics was studied, and the effects of carboxyl equivalent, viscosity and the mole ratio of raw materials such as Vi-ASO-1 to MA on the Vi-CAS-1 performance were also investigated carefully. The results shows that, the elasticity and flexibility of fabrics treated by Vi-CAS-1 significantly increase. And when cooperate with the silicone which contains Si-H (PHMS-0.16 %) in application, the compounded Vi-CAS-1 can improve the fabric water-repellency to some extent, as compared with the fabric treated only with Vi-CAS-1.

scholarly journals Ekstraksi senyawa fenolik antioksidan dari daun dan tangkai gambir

2018 ◽  
Vol 12 (2) ◽  
pp. 250
Author(s):  
Margareth Gani ◽  
Yesisca Cuaca ◽  
Aning Ayucitra ◽  
Nani Indraswati
Keyword(s):  
Antioxidant Activity ◽  
Solvent Extraction ◽  
Ethyl Acetate ◽  
Modern Medicine ◽  
Ethanol Solution ◽  
Total Phenolic ◽  
Acetate Solution ◽  
Extraction Temperature ◽  
Extraction Condition ◽  
Solvent Extraction Method

Extraction of phenolic compounds from leaves and stems of uncaria gambirGambir (Uncaria gambir) contains catechin polyphenols (catechins) which is useful as natural antioxidant to counteract free radicals. Gambir may also be used in modern medicine, also as paint or dye clothing. The objective of this research was to study the effect of type of solvent, solvent concentration, and extraction temperature to the yield and Total Phenolic Content (TPC) of extracts. Gambir was firstly blended without the addition of water prior to extraction using a solvent extraction method. The filtrate was separated from solid residue and evaporated to obtain extract powder. The yield and TPC of the resulting extract powder were then analyzed. Antioxidant activity and catechins content of extracts were also studied. As result, the following extraction condition gave extracts with the highest yield and TPC: with 50% ethanol solution as solvent at 75 oC gave 11.12% and 52.352 g GAE/100 g gambir extract, respectively; whilst with 70% ethyl acetate solution as solvent at 65 oC gave 5.28% and 59.346 g GAE/100 g gambir extract, respectively. The antioxidant activity of extracts, calculated as IC50, for solvent ethanol and ethyl acetate were as follows: 8.9 mg extract/mL and 13.8 mg extract/mL, respectively; whilst the catechins content of extracts were 62,18% and 44,85%, respectively.Keywords: Uncaria gambir, solvent extraction, catechins, antioxidants AbstrakGambir (Uncaria gambir) mengandung polifenol katekin (catechin) yang bermanfaat sebagai bahan antioksidan alami yang dapat menangkal radikal bebas. Selain itu, gambir juga dimanfaatkan dalam pembuatan obat-obatan modern dan pewarna cat atau pakaian. Penelitian ini bertujuan untuk mempelajari pengaruh jenis pelarut, konsentrasi pelarut, dan suhu ekstraksi terhadap perolehan dan kandungan senyawa fenolik (TPC) ekstrak gambir. Daun dan tangkai gambir mula-mula diblender tanpa penambahan air. Proses ekstraksi gambir dilakukan pada berbagai jenis pelarut, konsentrasi pelarut, dan suhu ekstraksi denganmetode ekstraksi pelarut. Setelah padatan dipisahkan dengan pelarutnya, pelarut diuapkan untuk mendapatkan serbuk ekstrak gambir. Serbuk ekstrak gambir dianalisis perolehan dan kandungan senyawa fenoliknya. Aktivitas antioksidan dan kadar katekin ekstrak juga dianalisis. Ekstrak daun gambir dengan perolehan dan TPC tertinggi untuk pelarut etanol (11,12% dan 52,352 g GAE/100 g gambir ekstrak) diperoleh pada konsentrasi etanol 50% dan suhu ekstraksi 75oC. Untuk pelarut etil asetat, perolehan dan TPC tertinggi (5,28% dan 59,346 g GAE/100 g gambir ekstrak) diperoleh pada konsentrasi etil asetat 70% dan suhu ekstraksi 65 oC. Pada masing-masing kondisi terbaik tersebut, ekstrak yang didapat memiliki aktivitas antioksidan (dalam IC50) dan kadar katekin sebesar 8,9 mg ekstrak/mL dan 62,18% untuk ekstraksi dengan pelarut etanol serta 13,8 mg ekstrak/mL dan 44,85% untuk pelarut etil asetat.Kata kunci: Uncaria gambir, ekstraksi pelarut, katekin, antioksidan 

scholarly journals Alkaline-based curcumin extraction from selected zingiberaceae for antimicrobial and antioxidant activities

2019 ◽  
Vol 48 (4) ◽  
pp. 293-300 ◽  
Author(s):  
Rashidi Othman ◽  
Mohd Akram Abdurasid ◽  
Noraini Mahmad ◽  
Nurrulhidayah Ahmad Fadzillah
Keyword(s):  
Ethyl Acetate ◽  
Extraction Method ◽  
Antioxidant Activities ◽  
Inhibition Zone ◽  
Single Peak ◽  
Diffusion Method ◽  
Powdered Sample ◽  
Acetate Solution ◽  
Content Type ◽  
Freeze Dried

Purpose The purpose of this paper is to extract, characterise and quantify curcumin from selected Zingiberaceae of “kunyit” or turmeric (Curcuma longa), “temu lawak” or Javanese turmeric (Curcuma xanthorrhiza), “temu pauh” (Curcuma mangga), “lempoyang” (Zingiber zerumbet) and “bonglai” (Zingiber cassumunar) using alkaline and chemical-based extraction method for antimicrobial and antioxidant activities. Design/methodology/approach Through the alkaline-based extraction method, all parts of rhizome samples were freeze-dried for 72 h before grounded into a fine powder and kept at −20°C. The powdered sample (0.1 g) was weighed and placed in a 50 mL tube. About 20 mL of 2 M NaOH solution was added into the tube. The solution was allowed to stand for 30 min. Then, 20 mL of ethyl acetate was added into the tube. The solution was mixed well then centrifuged at 13,500 rpm for 3 min. The upper layer was collected using a pipette. The process was repeated until the upper layer became almost colourless. The collected ethyl acetate solution was concentrated using a rotary evaporator to remove the ethyl acetate from the extracted compound. The concentrated curcumin was placed in a universal bottle, which was then dried from the remaining ethyl acetate using nitrogen drying process. The dried curcumin was then stored inside the freezer at −20ºC. The antimicrobial activities were using agar diffusion method against bacterial and fungi, while the antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay. Findings All the samples successfully showed a single peak (curcumin) that gained from the high-performance liquid chromatography (HPLC) chromatogram analysis (at 425 nm) using the alkaline-based extraction method and the highest curcumin content was in turmeric (12.95 ± 1.07mg/g DW). At 10.0 mg/mL curcumin concentration, the best antibacterial activity was against on methicillin-resistant staphylococcus aureus (MRSA) with 7.50 ± 0.71 mm inhibition zone, while the best antifungal activity was against on Aspergillus niger with 8.00 ± 0.41 mm inhibition zone. The DPPH antioxidant test resulted in the highest inhibition (110.41 per cent) was at 0.25 mg/mL curcumin concentration. Originality/value Through HPLC analysis, all samples successfully showed a single peak of curcumin at 425 nm. The total carotenoid determination from turmeric revealed that the samples content was substantially higher using alkaline-based extraction (18.40 ± 0.07 mg/g DW) compared to chemical-based extraction (9.42 ± 0.20 mg/g ± SD).

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