scholarly journals Oxidation of 3-Carene with Red Lead in Glacial Acetic Acid and Acetic Anhydride

1974 ◽  
Vol 23 (7) ◽  
pp. 420-422
Author(s):  
Yoshiharu MATSUBARA ◽  
Yoshihito FUJIHARA ◽  
Yutaka SAKAI ◽  
Makoto SANO
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Glacial Acetic Acid ◽  
Red Lead

1,4-Dinitroimidazole and Derivatives. Structure and Thermal Rearrangement

1989 ◽  
Vol 42 (8) ◽  
pp. 1281 ◽  
Author(s):  
MR Grimmett ◽  
ST Hua ◽  
KC Chang ◽  
SA Foley ◽  
J Simpson
Keyword(s):  
Molecular Structure ◽  
Acetic Acid ◽  
Acetic Anhydride ◽  
Glacial Acetic Acid ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Thermal Rearrangement

Nitration of 4-nitroimidazole in acetic anhydride/glacial acetic acid gives 1,4-dinitroimidazole. The crystal and molecular structure of this compound have been determined by direct methods. Crystals are orthorhombic; P212121, a 5.853(3), b 9.591(8), c 10.392(5) � , V 583.4(7) � 3 , Dm 1 .76 g cm-1, Dc, 1 .80 g cm-1 (Z = 4); λ 0.71069 � ; T 173 K. The structure was refined to R = 0.048 for 926 reflections [I > 2 σ(1)]. Both 2-methyl-4-nitro- and 5-methyl-4-nitro-imidazoles N-nitrate under the same conditions. When heated in solution at 100-140�C 1,4-dinitro- and 2-methyl-1,4-dinitro-imidazoles rearrange to give C-nitro isomers and some denitration products, but 5(4)-methyl-1,4(5)-dinitroimidazole failed to give identifiable products.

STUDIES OF RDX AND RELATED COMPOUNDS: III. THE REACTION TO FORM RDX FROM AMMONIUM NITRATE AND FORMALDEHYDE IN ACETIC ANHYDRIDE

1951 ◽  
Vol 29 (5) ◽  
pp. 377-381 ◽  
Author(s):  
A. Gillies ◽  
H. L. Williams ◽  
C. A. Winkler
Keyword(s):  
Acetic Acid ◽  
Nitric Acid ◽  
Acetic Anhydride ◽  
Ammonium Nitrate ◽  
Glacial Acetic Acid ◽  
Related Compounds

This reaction at 35°C. exhibits a behavior indicative of the presence of an intermediate in the reaction. Reaction of paraformaldehyde and ammonium nitrate in glacial acetic acid resulted in the isolation of hexamine dinitrate. Evidence is presented to indicate that formation of hexamine dinitrate, accompanied by the production of nitric acid, is responsible for the production of RDX in the acetic anhydride system.

Nonaqueous Titration of Halides of Nitrogenous Bases, Using Trifluoromethyl Sulfonic Acid

1986 ◽  
Vol 69 (4) ◽  
pp. 620-624 ◽  
Author(s):  
N Aziz Zakhari ◽  
K Artur Kovar
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Perchloric Acid ◽  
Sulfonic Acid ◽  
Glacial Acetic Acid ◽  
Visual Detection ◽  
Phenothiazine Derivatives ◽  
Solvent Systems ◽  
Anhydrous Acetic Acid

Abstract Trifluoromethyl sulfonic acid in glacial acetic acid has been compared with perchloric acid as a titrant in 4 solvent systems: glacial acetic acid, acetic anhydride, a mixture of both, and acetone. The comparison was limited to the determination of halides of nitrogenous bases with and without the use of mercury(II) acetate reagent. The results of the visual titrations showed that both acids are comparable tit rants. However, trifluoromethyl sulfonic acid proved to be superior to perchloric acid in potentiometric titrations carried out in acetic acid-acetic anhydride mixtures. Moreover, the nonoxidizing properties exhibited by trifluoromethyl sulfonic acid proved advantageous over perchloric acid in the visual detection of end points in the titration of phenothiazine derivatives in anhydrous acetic acid, using crystal violet indicator.

scholarly journals SINTESIS DAN KARAKTERISASI SELULOSA ASETAT DARI ALFA SELULOSA TANDAN KOSONG KELAPA SAWIT

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
M. Topan Darmawan ◽  
Muthia Elma ◽  
M. Ihsan
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Water Content ◽  
Cellulose Acetate ◽  
Sodium Acetate ◽  
Glacial Acetic Acid ◽  
Photographic Film ◽  
Ftir Analysis ◽  
Fiber Membrane ◽  
Acetyl Content

Selulosa asetat merupakan senyawa turunan selulosa yang sering digunakan sebagai serat, membran, dan film fotografi dalam industri. Tujuan dari penelitian ini adalah mengetahui pengaruh waktu asetilasi terhadap karakter selulosa asetat yang dihasilkan. Adapun proses yang digunakan dalam penelitian ini adalah proses cellanase dengan bahan baku tandan kosong kelapa sawit (TKKS). Tahapan reaksinya adalah aktivasi, asetilasi, dan hidrolisis. Aktivasi dilakukan di dalam labu leher tiga dengan penambahan asam asetat glacial 50 mL dan diaduk selama 3 jam pada kecepatan 125 rpm. Selanjutnya ditambahkan asetat anhidrida 15 mL sebagai agen asetilasi. Asetilasi dilakukan dengan variasi waktu, 2; 2,5; 3; dan 3,5 jam. Pada tahapan hidrolisis, ditambahkan air 2 mL dan asam asetat glacial 5 mL. Reaksi berlangsung selama 30 menit. Selanjutnya ditambahkan 1 gram natrium asetat untuk netralisasi yang berlangsung selama 5 menit. Kemudian dilakukan pencucian sampai bau asam asetat hilang. Tahapan terakhir adalah pengeringan yang dilakukan dengan suhu 55ºC selama 6 jam. Produk yang dihasilkan kemudian dianalisis kadar air, kadar asetil, rendemen dan gugus fungsi menggunakan analisa FTIR. Selulosa asetat yang terbaik diperoleh pada waktu asetilasi selama 2,5 jam dengan  kadar  asetil  40,36%, kadar  air  4.43%,  dan  rendemen 153,8%.Kata kunci: cellanase, selulosa, selulosa asetat. Cellulose acetate is a cellulose derivative which is often used as a fiber, membrane, and photographic film in industry. The  objectives  of  this  study  were  to determine the effect of acetylation time on the character of cellulose acetate. The process used in this study is the process of cellanase with α-cellulose of empty palm oil bunches materials. Stages of reaction are activation, acetylation, and hydrolysis. Activation was performed in a three-neck flask with the addition of 50 mL glacial acetic acid and stirred for 3 hours at 125 rpm. Then added 15 mL acetic anhydride as acetylation agent. Acetylation was performed by varying the time, 2; 2.5; 3; And 3.5 hours. At the hydrolysis stage, 2 mL of water and 5 mL glacial acetic acid were added. The reaction lasts for 30 minutes. Then added 1 gram of sodium acetate for neutralization lasts 5 minutes. then do the washing up to the smell of acetic acid disappeared. The final stage is the drying is done at a temperature of 55ºC for 6 hours. The resulting product was then analyzed for water content, acetyl content, rendement and functional groups using FTIR analysis. Cellulose acetate are best obtained at the time of acetylation for 2.5 hours with acetyl content of 40.36%, water content 4:43%, and a yield of 153.8%.Keywords: acetate cellulose, cellanase, cellulose.

scholarly journals HISTOCHEMICAL AZO COUPLING OF PROTEIN HISTIDINE BRUNSWIK'S NITRATION METHOD

1972 ◽  
Vol 20 (11) ◽  
pp. 929-937 ◽  
Author(s):  
R. D. LILLIE ◽  
P. T. DONALDSON
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Alkaline Solution ◽  
Glacial Acetic Acid ◽  
Oxides Of Nitrogen ◽  
Azo Coupling ◽  
Azure A ◽  
Acid Ph ◽  
Water Ph

The xanthoproteic reaction is accomplished with only 20% HNO3 with glacial acetic acid (HAc) as the solvent; in water 40% HNO3 is required. Tyrosine and 3-mononitrotyrosin readily azo-couple in alkaline solution with fresh p-nitrodiazobenzene in vitro; 3,5-dinitrotyrosine does not. In vitro p-nitrodiazobenzene at pH 8.5 does not couple with histidine, tryptophan or tyrosine after overnight nitration in tetranitromethane (TNM)-pyridine-0.1 N HCl 1:20:40. Histochemical nitration of tissue adequate to prevent the p-diazobenzenesulfonic acid, pH 1-0.02% azure A sequence reaction of hair medulla and arterial elastin of man, dog and rodents can be achieved by 40% HNO3 in glacial acetic acid-acetic anhydride (Ac2O) mixtures. Acetic anhydride should be 10% only, to restrict evolution of brown oxides of nitrogen and prevent undue section losses. Exposures of 4 hr at 3°C to 4:5:1 HNO3:HAc:Ac2O are effective and well tolerated. Nitration is also effectively accomplished by 6-hr 25°C exposures to mixtures of 1% tetranitromethane-pyridine and two volumes of water (pH 8.2) or 0.1 N HCl (pH 6.6). Even 10% TNM in dry pyridine and 2.5% in 16.3% pyridine alcohol (6 hr), 3°C exposures gave only partial tyrosine blockades. The pyridine-water TNM mixtures also prevented the Morel-Sisley tyrosine reaction and, with greater exposures, the postcoupled benzylidene indole reaction of tryptophan as well. Sites reactive to diazobenzenesulfonic acid-azure A after the best nitrations are probably assignable largely to histidine, though the presence of some unblocked tryptophan, purines and other reactive substances must be considered.

scholarly journals HISTOCHEMICAL ACYLATION OF ALDEHYDES PRODUCED BY PERIODIC ACID OXIDATION

1966 ◽  
Vol 14 (7) ◽  
pp. 529-537 ◽  
Author(s):  
R. D. LILLIE
Keyword(s):  
Acetic Acid ◽  
Sulfuric Acid ◽  
Acetic Anhydride ◽  
Glacial Acetic Acid ◽  
Periodic Acid ◽  
Potassium Hydroxide Solution ◽  
Acid Oxidation ◽  
Enol Acetate ◽  
Periodic Acid Oxidation ◽  
Schiff Reaction

Aldehydes produced in tissue sections by periodic acid oxidation are readily acetylated or benzoylated so as to weaken or completely prevent the Schiff and other chromogenic reactions. The reactivity of acylated aldehydes to Schiff reagent is promptly restored by saponification in alcoholic potassium hydroxide solution (10-20 min, 1% KOH, 70% ethanol). Benzoylation with 5-10% benzoyl chloride in pyridine gave the promptest, most complete and consistent aldehyde blockade, which was somewhat inferior on addition of 0.5% sulfuric acid. Pyridine acetic anhydride mixtures, 25, 40 and 50% gave partial to complete blockade. Addition of 0.25-0.5% sulfuric acid did not give consistent effects. Acetic anhydride at 60°C gave partial blockade at ½-5 hr, on addition of 0.01-0.25% sulfuric acid total or subtotal blockade was achieved. Acetylation in alcohol gave inferior resutlts. Use of 25% acetic anhydride ims glacial acetic acid gave inferior results; addition of 0.25% sulfuric acid produced total to subtotal blockade at 4-5 hr. Glacial acetic acid was without appreciable blockade effect. Sulfation in 10% and 25% H2SO4/glacial acetic acid failed to blockade aldehydes. Experiments with the peracetic acid Schiff reaction for ethylene groups indicate that some proportion of enol monobenzoate may be formed, and that with the various acetylation techniques a smaller or negligible proportion of enol acetate is formed. Acetic anhydride with 0.25% H2S04 at 60° appears to form only aldehyde diacetate. Experiments with the bromination silver techniques did not give satisfactory results.

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