Anhydride In Presence Research Articles

Protection of aldehydes, hydroxy compounds with acetic anhydride in presence of sulfonic acid functionalized ionic liquid

Protection of aldehydes, hydroxy compounds with acetic anhydride in presence of sulfonic acid functionalized ionic liquid

Mechanism and dynamics of Baeyer–Villiger oxidation of furfural to maleic anhydride in presence of H2O2 and Au clusters

Mechanism and dynamics of Baeyer–Villiger oxidation of furfural to maleic anhydride in presence of H2O2 and Au clusters

Synthesis and discovery of a water-soluble ureid of galodif with succinic acid

For the first time, a new acyl ureide of the anticonvulsant and anti-alcohol drug galodif (3-chlorobenzhydryl urea) with succinic acid was obtained and studied. The synthesis was carried out by the acylation of galodif with succinic anhydride in presence of certain acids. Unlike galodif, which is practically insoluble in water, the resulting benzhydryl ureide is soluble in aqueous media and can potentially exhibit greater bioavailability and can be used as a liquid dosage form and prodrug with prolonged action.

Ultrafast Epoxy‐Anhydride Photopolyaddition Reaction

AbstractThe conventional epoxy/anhydride reaction is quite slow (more than one hour to reach full conversion at room temperature (RT)) and usually requires thermal treatment at rather high temperature. Ideally, the reaction should be triggered by light for on demand systems i.e. very fast polymerizations (in few seconds) can be carried out in mild conditions (at RT with low energy consumption using cheap and safe light emitting diode (LED) light). In this work, a new approach is proposed with an ultrafast epoxy/anhydride photopolyaddition reaction that can be triggered by near‐UV/visible light. Therefore, a photoinitiating system is developed to cure epoxides in presence of anhydrides as hardeners without any external heat and in a short time scale i.e. few seconds upon light vs. hours at RT without light. Excellent polymerization performances can be observed upon LED@405nm irradiation with full epoxy function conversion. The polymerization kinetics are followed both by real‐time FTIR and real‐time photorheology experiments. As example of the high performance of this new photoactivated epoxy/anhydride process, the curing of epoxy/glass fibre composites is presented. Remarkably, an excellent depth of cure can be obtained in only 20 seconds of irradiation with a LED@405 nm.

Аn improved method for preparation of heptyl (4-trifluoroacetyl) benzoate

A convenient three-step method for synthesis of heptyl (4-trifluoroacetyl)benzoate, an important neutral anion carrier, has been developed. The key step of the method is acylation of toluene by trifluoroacetic anhydride in presence of aluminium chloride at –8 – –10 oC. The procedure gives high overall yield and, unlike the earlier methods, does not include any organometallic reagents, therefore allowing scaling it up to several hundred grams, that makes the target compound much more readily available.

Synthesis and Characterization of Some New Heterocyclic Compounds Derived from Benzothiazole

The present work involves study of some new 1,3-oxazepine and diazepines derivatives by cycloaddition reaction between Schiff s bases and (Succinic imide, phthalic imide, and 3-nitophthalic) anhydride with dry benzene as a solvent. Oxazepine and diazepines derivatives from 4-chloro-6-nitrobenzo[d]thiazol-2-amine were synthesized. These derivatives were synthesized by the reaction of Schiff base with different anhydrides in presence of dry benzene. The starting material was 4-Chloro-6-nitro 2-aminobenzothiazole which prepared from 2-Chloro -4-nitroaniline and ammonium thiocyanate with presence of bromine and sodium acetate. The prepared compounds have been characterized by melting points and some physical properties besides the FT-IR,H-NMR spectra. The purity for these compounds was checked by TLC.

Synthesis and Characterization of New Compounds Derived from N-(mono chloro) Adipoyl Phthalimide

This work contain preparation new compounds derived from N-(mono chloro) adip phthalimide (1) in three steps, the first step was prepare Schiff bases compounds from the reaction of N-hydrazino adip phthalimide (2) with different aldehydes and ketones. The second step was prepared thiazolidine ring by the reaction of prepared Schiff bases with mercapto acetic acid. The third step was included preparation of imide ring by react compound (2) with different anhydrides in presence of glacial acetic acid. All the prepared compounds were characterized by FT-IR spectra, some of them by H1-NMR, physical properties and measurements of thermal stability by TG. technique.

Aromatic C-acylation of Phenols by using Acid and Acid Anhydride in Presence of Lewis Acid Catalyst

Aromatic C-acylation of Phenols by using Acid and Acid Anhydride in Presence of Lewis Acid Catalyst

SYNTHESIS OF SOME NEW HETEROCYCLIC COMPOUNDS DERIVED FROM N-(Ñ-PHENYL GLYCYL) SACCHARIN AND STUDY THEIR BIOLOGICAL ACTIVITY

Objective: In the present work, a variety of new heterocyclic compounds namely aza-β- lactam, cyclicimides, 1,3-thiazole, and 1,2,4-triazole.Methods: Procedure includes the synthesis of aza-β- lactam, cyclic imides, 1,3-thiazole, and 1,2,4-triazole. The synthesis was carried out in eleven steps using N-(Ñ-substituted phenylglycyl) saccharin derivatives (1a,b) as a starting material and converted to benzoic acid derivatives (2a,b) and then to ester derivatives (3a,b), which finally convers to benzohydrazide derivatives (4a,b). The cyclization of (4a,b) with carbon disulfide and hydrazine hydrate (80%) in the presence of potassium hydroxide gives 1,2,4-triazole compounds (5a,b), and subsequently (5a,b) derivatives reacted with different aromatic aldehydes in the presence of few drops of glacial acetic acid to give Schiff bases (6a-f). Compounds (7a-b) was prepared by the reaction of compounds (4a,b) with chloroacetyl chloride. 1,3-thiazole derivatives (8a,b) were synthesized through the cyclization of compounds (7a,b) with thiourea. Schiff bases (9a-f) were obtained by condensation of (4a,b) with different aromatic aldehydes in the presence of few drops of glacial acetic acid. Aza-β-lactam compounds (10a-f) were prepared by the cycloaddition of Schiff-bases (9a-f) with phenyl isocyanate through [2+2] cycloaddition reaction. Reaction (4a,b) with various acid anhydrides in presence of acetic acid gave the corresponding cyclic imide (11a-f). The newly prepared.Results: The results showed that compounds (5a) and (10e) have a good activity against Gram-positive bacterium and no activity against Gram-negative bacterium, compared to standard drugs (ciprofloxacin and amoxicillin), while compounds (8a) and (6b) have a high activity against fungi, compared to standard drugs (metronidazole benzoate), and the other tested compounds have low-to-moderate activity.Conclusion: 1,2,4-triazole is a most potent assemblage of Gram-positive bacterium retardants and cyclic imides are a most potent assemblage of fungi retardants.

Synthesis & characterization of novel silicone dendrimers as base stock for high performance lubricants

The silicone core GI dendrimers having terminal Si-H groups reacted with maleic anhydride in presence of Speier's catalyst to afford anhydride terminated dendrimers. These anhydride dendrimers were further reacted with long chain aliphatic alcohols in presence of lower valent tin oxide as catalyst to synthesize novel second generation complete neutral silicone ester dendrimers. These high performance silicone esters dendrimers can be used for different avionic applications and also as base stock material for lubricants. Characterizations of the dendrimers were carried out by elemental analysis; Fourier transforms infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance spectroscopy (1H NMR spectroscopy). Physical properties like density, viscosity, flash point and pour point of the dendrimers were also studied. Vapor pressure osmometery (VPO) and gel permeation chromatography (GPC) were used for measuring the molecular weight and molecular weight distribution of the dendrimers.

Facile preparation of EDTA‐functionalized chitosan magnetic adsorbent for removal of Pb(II)

ABSTRACTA novel magnetic adsorbent (EDTA/chitosan/PMMS) was facilely prepared by reacting chitosan with EDTA anhydride in presence of PEI‐coated magnetic microspheres. The as‐synthesized EDTA/chitosan/PMMS was characterized by XRD, SEM, TGA, FT‐IR, and VSM, and then employed in removal of heavy metals of Pb(II) from aqueous solution. The results of the batch adsorption experiments revealed that the adsorbents had extremely high uptake capacities for Pb(II) in the pH range of 2 to 5.5, and the adsorption kinetics for EDTA/chitosan/PMMS was consistent with the pseudo–second‐order kinetic model. Moreover, its equilibrium data were fitted with the Langmuir isothermal model well, which indicated that the adsorption mechanism was a homogeneous monolayer chemisorptions process. The maximum adsorption capacity of EDTA/chitosan/PMMS for Pb(II) was found to be 210 mg g−1 at pH 4 (30°C), and further reuse experiments results suggested that EDTA/chitosan/PMMS could be a potential recyclable magnetic adsorbent in the practical wastewater treatment. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42384.

Non-isothermal crystallization behavior of compatibilized polypropylene/recycled polyethylene terephthalate blends

A binary blend of polypropylene (PP)/recycled polyethylene terephthalate (rPET) and ternary blends of PP/rPET (80/20 w/w) compatibilized with different amounts (5 and 15 mass%, respectively) of a new compatibilizer, PP grafted with maleic anhydride in presence of diallyl phthalate (PP-g-MAH/DAP), are prepared using a twin-screw extruder. The non-isothermal crystallization kinetics and the crystallization morphologies are investigated by differential scanning calorimetry and polarized optical microscopy (POM), respectively. The crystallization temperature and rate of the binary blend increase during the non-isothermal crystallization process, indicating that rPET phase has nucleation ability for crystallization of the PP matrix. However, the crystallization temperatures and rates of the ternary blends slightly decrease because of the chemical reaction between MAH and the rPET terminal groups. Applying the equations proposed by Jeziorny, Ozawa, and Mo to analyze the non-isothermal crystallization kinetics of pure PP and PP in the binary and ternary PP/rPET blends, agreement is found between the experimental results and Mo method. The crystallization activation energy increases in the binary PP/rPET blend, which is ascribed to the confinement effect on the motion of the PP chains by large rPET particles, and this confinement effect is mitigated with the inclusion of PP-g-MAH/DAP. POM observation confirms the heterogeneous nucleation of rPET on PP and the restriction of crystallization of PP by the incorporation of PP-g-MAH/DAP.

Novel 1,2,3-Triazole Derivatives as Antimicrobial Agents

2-Substituted benzimidazoles 3a-c was prepared via condensation of ethyl pyruvates 2a-c with 2-phenylenediamine in glacial acetic acid. Pyrrolo[1,2- a ]benzimidazole derivatives 5 and 8 were prepared via cyclocondensation of compounds 3a,b with phosphorus oxychloride or acetic anhydride in presence of sodium acetate respectively. Reactivity of pyruvate 2 towards 2-aminophenol, hydroxylamine and cyanothioacetamide was also investigated. They exhibited potent antimicrobial activity comparable to clinical drugs such as ciprofloxacin and ketoconazole. Compounds 3a , 11 and 13 showed excellent antimicrobial activity against all the tested microbes, and Compound 11 showed lower MIC values against all the tested organisms.

Fourier Transform Infrared Spectroscopy Study on Cation adsorption on Viscose Rayon Succinate

Ion-exchange materials have been considered as suitable material for the recovery of heavy metals in water. A viscose rayon succinate, synthesized from viscose rayon and succinic anhydride in presence of DMSO, to remove trace bivalent metal ions such as Ag+, Cu2+, Ni2+, Pb2+, Zn2+ and Cr3+, was studied using FT-IR for the behavior of metal adsorption. Both esterification and carboxyl bonding of viscose rayon succinate were assigned essentially at 1729 and 1693cm-1, respectively. And the essential band of bonding between metal and the material was determined at 1625cm-1. The available adsorption capacity of this fiber was 6.2 mequiv/g. The adsorption of metal ions on the viscose rayon succinate follows the order of Cu2+>Cr3+>Ni2+>Pb2+>Zn2+>Ag+ with maximum adsorptions capacities 4.2, 1.42, 0.91, 0.83, 0.69 and 0.35 mmol/g, respectively.DOI: http://dx.doi.org/10.5564/mjc.v12i0.189 Mongolian Journal of Chemistry Vol.12 2011: 136-141

Solvent-Free Synthesis of Some1-Acetyl Pyrazoles

Some N-acetyl pyrazoles including 1-(3-(3,4-dichlorophenyl)-5-(substituted phenyl)-4,5-dihydro- 1 H-pyrazole- 1-yl) ethanones have been synthesised by solvent free cyclization cum acetylation of chalcones like substituted styryl 3,4- dichlorophenyl ketones using hydrazine hydrate and acetic anhydride in presence of catalytic amount of fly-ash: H2SO4 catalyst. The yield of these N-acetyl pyrazole derivatives are more than 75%. The synthesised N-acetyl pyrazoline derivatives were charac- terized by their physical constants and spectral data

Synthesis and Spectral Correlation Study of some 3-(3,4-dichlorophenyl)-5-(Substituted Phenyl)-4,5-dihydro-<sup>1</sup><i>H</i>-Pyrazole-1-yl-Ethanones

Some N-acetyl pyrazoles including 3-(3,4-dichlorophenyl)-5-(substituted phenyl)-4,5-dihydro-1H-pyrazole-1-yl-ethanones have been synthesised by solvent free cyclization cum acetylation of chalcones including substituted styryl 3,4-dichlorophenyl ketones using hydrazine hydrate and acetic anhydride in presence of catalytic amount of fly-ash: H2SO4 catalyst. The yield of these N-acetyl pyrazole derivatives are more than 75%. The synthesised N-acetyl pyrazoline derivatives were characterized by their physical constants and spectral data. The infrared spectral νC=N and C=O (cm-1) frequencies, NMR chemical shifts (δ, ppm) of Ha, Hb, Hc, CH3 protons, C=N, C=O and CH3 carbons of 1-(3-(3,4-dichlorophenyl)-5-(substitutedphenyl)-4,5-dihydro-1H-pyrazole-1-yl) ethanones have been assigned and correlated with Hammett substituent constants and Swain-Lupton’s parameters using single and multi-regression analysis. From the results of statistical analyses the effect of substituents on the above group frequencies and chemical shifts of the acetylated pyrazoles were discussed.

Synthesis and Spectral Correlation Study of some 3-(3,4-dichlorophenyl)-5-(Substituted Phenyl)-4,5-dihydro-<sup>1</sup><i>H</i>-Pyrazole-1-yl-Ethanones

Some N-acetyl pyrazoles including 3-(3,4-dichlorophenyl)-5-(substituted phenyl)-4,5-dihydro-1H-pyrazole-1-yl-ethanones have been synthesised by solvent free cyclization cum acetylation of chalcones including substituted styryl 3,4-dichlorophenyl ketones using hydrazine hydrate and acetic anhydride in presence of catalytic amount of fly-ash: H2SO4 catalyst. The yield of these N-acetyl pyrazole derivatives are more than 75%. The synthesised N-acetyl pyrazoline derivatives were characterized by their physical constants and spectral data. The infrared spectral νC=N and C=O (cm-1) frequencies, NMR chemical shifts (δ, ppm) of Ha, Hb, Hc, CH3 protons, C=N, C=O and CH3 carbons of 1-(3-(3,4-dichlorophenyl)-5-(substitutedphenyl)-4,5-dihydro-1H-pyrazole-1-yl) ethanones have been assigned and correlated with Hammett substituent constants and Swain-Lupton’s parameters using single and multi-regression analysis. From the results of statistical analyses the effect of substituents on the above group frequencies and chemical shifts of the acetylated pyrazoles were discussed.

Synthesis and Characterization of Substituted Phenyl Azetidines as Potential Antimicrobial Agents

The reaction of 2-(4-bromo phenyl) methyl cyanide ( 1a ) with ethylchloroformate in the presence of n-butyl lithium gave ethyl-2-(4-bromo phenyl)-2-cyano acetate ( 2a ). 2a on reduction with sodium borohydride yields 3-amino-2-(4-bromo phenyl) propan-1-ol ( 3a ). Compound 3a on further reaction with tert butyloxy anhydride in presence of triethylamine afford tert-butyl-2-(4-bromo phenyl)-3- hydroxy propyl carbamate ( 4a ). 4a on treatment with tosyl chloride gave 2-(4-bromo phenyl)-3- (tertiarybutyloxy carbonyl amino)-propan-1-ol-(4-toluene sulphonate) (5a ). Compound 5a on cyclization followed by hydrolysis gave 3-(4-bromo phenyl) azetidine ( 7a ). Compounds 2b-2e, 3b-3e , 4b-4e, 5b-5e, 6b-6e and 7b-e were synthesized by a similar method. The compounds are characterized by elemental analysis, IR, 1 H NMR and Mass spectral analysis and screened for antimicrobial activity.

Synthesis of Polymers from Fatty Alcohol and Acrylic Acid and its Impact on Tribological Properties

Anhydride copolymers were synthesized from acrylic acid and fatty alcohols (C12- C18, C18:1). These n-alkyl acrylates were treated with maleic anhydride in presence of hydrogen peroxide in second step, to form anhydride copolymer. The anhydride copolymer further reacted to n-butylamine to form poly (n-acrylate-co-nbutylmalemide). The compounds were used as pour point depressant (PPD) additive. The synthesized experimental pour point depressants were added in different concentrations to conventional base stock (150N and 500N), which had no other additive content before. Synthesized additives were effective as viscosity index improver but also lowered the pour point. These results were comparable with industrial product. Furthermore all additives showed antiwear (AW) and extreme pressure (EP) properties. The resultant anhydride copolymer can act as multifunctional additive, which is novelty of the work.

NaHSO4-SiO2 as an efficient and chemoselective catalyst, for the synthesis of acylal from aldehydes under, solvent-free conditions

BackgroundStructurally diverse aldehydes are successfully converted into acylals (1,1-diacetates) with acetic anhydride using NaHSO4-SiO2 as a mild, convenient and inexpensive catalyst under solvent-free conditions. The noteworthy features of the present system are shorter reaction times, and mild and solvent-free conditions. Furthermore, it offers chemoselective protection of aldehydes.ResultsBoth aromatic and aliphatic aldehydes reacts smoothly with acetic anhydride in presence of silica supported sodium hydrogen sulphate to afford the corresponding 1,1-diacetates in good to excellent yields. We studied competitive reactions for the acylation of aldehydes in the presence of ketones using silica supported sodium hydrogen sulphate as a catalyst. Using this catalytic system, the highly selective conversion of an aldehyde in the presence of ketone was observed.ConclusionsNaHSO4-SiO2 is a chemoselective and highly efficient catalyst for acylal formation from aldehydes. The advantages of this methodology over the reported methods is the availability of the starting materials, simplicity of acylation procedure, a clean work-up, a short reaction time, high yields and reusability.