NITROLYSIS OF HEXAMETHYLENETETRAMINE: II. NITROLYSIS OF l,5-ENDOMETHYLENE-3,7-DINITRO-1,3,5,7-TETRAZA-CYCLOÖCTANE (DPT)

1949 ◽  
Vol 27b (5) ◽  
pp. 462-468 ◽  
Author(s):  
A. F. McKay ◽  
George F Wright ◽  
H. H. Richmond
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Ammonium Nitrate ◽  
Acid Anhydride ◽  
Nitrogen Pentoxide ◽  
Linear Poly ◽  
Acetyl Nitrate ◽  
Nitrate Mixture

When 1,5-enedomethylene-3,7-dinitro-1,3,5,7-tetrazacycloöctane (DPT) is nitrolyzed with nitric acid – ammonium nitrate mixture the products are cyclic trimeric and tetrameric methylenenitramines (RDX and HMX). When the ammonium nitrate in this nitrolysis mixture is replaced by anhydrides such as nitrogen pentoxide or acetic anhydride then terminally esterified linear poly-methylenenitramines such as 1,9-dinitroxy-2,4,6,8-tetranitro-2,4,6,8-tetrazanonane and the 1,9-diacetoxy analogue respectively are obtained. Replacement of this nitric acid – anhydride mixture by acetyl nitrate does not produce the same type of nitrolysis. It is therefore concluded that nitric acid and an anhydride act independently, the former as a nitrolyzing agent and the latter as an esterifying agent. Alternatively the presence of ammonium nitrate serves to promote esterification and/or promote demethylolation.

Addition Reactions in the Nitration of Some Polycyclic Aromatic Compounds

1972 ◽  
Vol 50 (20) ◽  
pp. 3367-3372 ◽  
Author(s):  
A. Fischer ◽  
D. R. A. Leonard
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Nitro Group ◽  
Aromatic Compounds ◽  
Addition Reaction ◽  
Polycyclic Aromatic Compounds ◽  
Addition Reactions ◽  
Polycyclic Aromatic ◽  
Acetyl Nitrate

Reaction of 3-oxo-1,2,3,7,8,9,10,10a-octahydrocyclohepta[de]naphthalene with nitric acid in acetic anhydride gives two stereoisomeric 4-acetoxy-6a-nitro-3-oxo-1,2,3,4,6a,7,8,9,10,10a-decahydrocyclohepta[de]-naphthalenes as well as the expected nitro substitution products. Formation of these adducts from a substrate containing a meta-directing deactivating substituent shows that the 1,4-addition reaction of acetyl nitrate is more general than previously suspected. 1,4-Acetyl nitrate adducts are also formed from tetralin, benzsuberane, 5,6,7,8-tetrahydrocyclohepta[fg]acenaphthene, and 1,2,3,4,7,8,9,10-octahydrodicyclohepta[de,ij]naphthalene. Decomposition of the last two adducts gives in each case a product with the nitro group substituted into the alicyclic ring.

scholarly journals STUDIES ON RDX AND RELATED COMPOUNDS: IX. DETERMINATION OF NITRIC ACID AND ACETIC ANHYDRIDE IN BACHMANN LIQUORS

1953 ◽  
Vol 31 (3) ◽  
pp. 201-203
Author(s):  
R. H. Betts ◽  
R. S. Stuart ◽  
C. A. Winkler
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Ammonium Nitrate ◽  
Routine Analysis ◽  
Calcium Hypochlorite ◽  
Electrometric Method ◽  
Direct Titration ◽  
Related Compounds ◽  
External Indicator

An electrometric method for determination of nitric acid in RDX(B) liquors has been developed. The method is not largely affected by ammonium nitrate and acetic anhydride. A precision of ± 0.5% may be readily obtained. Acetic anhydride in RDX(B) liquors may be determined by direct titration with standard aniline–toluene solution at 0 °C., using calcium hypochlorite as an external indicator. In routine analysis, a precision of ± 2% may be obtained.

REACTIONS OF PHENYL-SUBSTITUTED HETEROCYCLIC COMPOUNDS: II. NITRATIONS AND BROMINATIONS OF 1-PHENYLPYRAZOLE DERIVATIVES

1963 ◽  
Vol 41 (6) ◽  
pp. 1540-1547 ◽  
Author(s):  
Misbahul Ain Khan ◽  
Brian M. Lynch ◽  
Yuk-Yung Hung
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Heterocyclic Compounds ◽  
Electrophilic Substitution ◽  
Chloroform Solution ◽  
Pyrazole Ring ◽  
Conjugate Acid ◽  
Acetyl Nitrate ◽  
Silver Sulphate ◽  
Mixed Acids

Nitrations of 1-phenylpyrazole (I), 1-p-biphenylylpyrazole (II), and 1,5-diphenylpyrazole by "acetyl nitrate" (nitric acid – acetic anhydride) occur selectively in the 4-position of the pyrazole ring, as do brominations of I and II in chloroform solution. These results are in agreement with R. D. Brown's calculations of localization energies for electrophilic substitution in pyrazole.However, nitration of I by mixed acids at 12° yields 1-p-nitrophenylpyrazole, and bromination of I by bromine in concentrated sulphuric acid in the presence of silver sulphate yields 1-p-bromophenylpyrazole.The variations in orientation of substitution can be rationalized if the reacting species of I in strongly acidic solvents is the conjugate acid, in which the pyrazole ring is deactivated by protonation.

Regioselective Nitration of m-Xylene Catalyzed by Zeolite Catalyst

2015 ◽  
Vol 68 (7) ◽  
pp. 1122 ◽  
Author(s):  
Xiongzi Dong ◽  
Xinhua Peng
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Zeolite Catalyst ◽  
Molecular Volume ◽  
Acetyl Nitrate ◽  
Regioselective Nitration ◽  
Excellent Selectivity

Nitration with nitric acid and acetic anhydride via acetyl nitrate as nitrating species is efficient with the substrate m-xylene as solvent. Zeolite Hβ with an SiO2/Al2O3 ratio of 500 was found to be the most active of the catalysts tried both in yield and regioselectivity in the nitration of m-xylene. The molecular volume of the reactants was calculated with the Gaussian 09 program at the B3LYP/6–311+G(2d, p) level and compared with the size of the zeolite Hβ channels. A range of other substrates were subjected to the nitrating system under the same conditions as those optimized for m-xylene and excellent selectivity was obtained.

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.

NITROLYSIS OF HEXAMETHYLENETETRAMINE: VI. RECOMBINATION OF FRAGMENTS DURING HEXAMETHYLENETETRAMINE NITROLYSIS IN ACETIC ANHYDRIDE

1949 ◽  
Vol 27b (6) ◽  
pp. 520-544 ◽  
Author(s):  
E. Aristoff ◽  
J. A. Graham ◽  
R. H. Meen ◽  
G. S. Myers ◽  
G. F Wright
Keyword(s):  
Acetic Acid ◽  
Nitric Acid ◽  
Acetic Anhydride ◽  
Ammonium Nitrate ◽  
Degradation Products ◽  
Stepwise Synthesis ◽  
Alternative Hypotheses ◽  
Enhanced Yield ◽  
By Products

Alternative hypotheses can account for the yield of more than one equivalent of Cyclonite from hexamine when the Bachmann reagents, ammonium nitrate, nitric acid, and acetic anhydride are used. In the nitrolysis, evidence for a stepwise synthesis from unit fragments is presented as the enhanced yield when methylenedinitramine is added with paraform to ammonium nitrate and acetic anhydride according to the Schiessler–Ross method for Cyclonite synthesis. However, this evidence is discounted because the expected by-product, 1,5-diacetoxy-2,4-dinitro-2,4-diazapentane is not found. Alternatively it is believed that the Bachmann reaction is actually a combination of the direct nitrolysis of hexamine with nitric acid, concurrent with a resynthesis of hexamine from the fragments produced by the nitrolysis. On this basis all by-products from the hexamethylenetetramine nitrolysis must be accounted as degradation products of hexamethylenetetramine and not capable of synthesis from unit fragments like formaldehyde, ammonia, and acetic acid. No exception has been found; the addition of acylamides to the Bachmann reaction mixture increases the yield of two by-products, 1-acyl-3,5-dinitro-1,3,5-triazacyclohexane and 1-acyl-3,5,7-trinitro-1,3,5,7-tetrazacycloöctane. It has been shown that these can be formed only from degradation products of hexamethylenetetramine such as 1,5-diaceto-3,7-endomethylene-1,3,5,7-tetrazacycloöctane and acetaminomethylhexamethylenetetramine nitrate.

STUDIES OF RDX AND RELATED COMPOUNDS: VII RELATION BETWEEN RDX AND HMX PRODUCTION IN THE BACHMANN REACTION

1952 ◽  
Vol 30 (10) ◽  
pp. 734-742 ◽  
Author(s):  
S. Epstein ◽  
C. A. Winkler
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Ammonium Nitrate ◽  
Deleterious Effect ◽  
Activation Energies ◽  
Related Compounds

The reactions to form RDX and HMX in Bachmann-type mixtures are comparable in respect of optimum nitric acid concentrations and in the fact that optimal amounts of acetic anhydride and ammonium nitrate are necessary for maximum yields of either explosive. The activation energies for formation of RDX and HMX were also found to be comparable, at 15 ± 1 kcal. per mole. However, withholding ammonium nitrate from the reaction mixture was found to have a more deleterious effect on RDX production than on HMX production. A mechanism is proposed which attempts in a general way to represent the relation between RDX and HMX production in the type of reaction mixtures used.

scholarly journals Nitration of Hydrolysis Lignin in Water-Aprotic Solvent Mixtures

2020 ◽  
pp. 184-192
Author(s):  
D.E. Lakhmanov ◽  
◽  
Yu.G. Khabarov ◽  
V.A. Veshnyakov ◽  
M.R. Yokubjanov
Keyword(s):  
Nitric Acid ◽  
Acetic Anhydride ◽  
Dimethyl Sulfoxide ◽  
Nitrogen Content ◽  
Aprotic Solvent ◽  
Maximum Yield ◽  
Hydrolysis Lignin ◽  
Solvent Mixtures ◽  
Constant Weight ◽  
Acetyl Nitrate

Industrial lignins are formed from native lignins during chemical or biochemical processing of plant raw materials. Lignins can be modified to produce valuable products, including monomers, polymeric materials, and composites. The article presents the results of a study of hydrolysis lignin nitration under various conditions. The aim of the study was to obtain a nitrated hydrolysis lignin with a maximum yield and maximum nitrogen content. Therefore, the nitration was carried out using nitric acid in a water-aprotic solvent binary mixtures (1,4-dioxane, dimethyl sulfoxide, tetrahydrofuran, dimethylformamide, acetonitrile). Acetyl nitrate, which is a mixed anhydride of nitric and acetic acids, was also used as a nitrating agent. In this regard, the consumption of acetic anhydride in the synthesis of acetyl nitrate was used taking into account the water present in concentrated nitric acid. Acetyl nitrate was obtained by the reaction of acetic anhydride and concentrated nitric acid at room temperature for 30 min. Acetyl nitrate is a mild nitrating agent opposed to nitric acid. Nitration was carried out under reflux in a boiling water bath for 2–5 min (with nitric acid) or 1–60 min (with acetyl nitrate). Upon completion of the nitration reaction, the products were filtered, washed with distilled water and dried to constant weight without heating. When nitration was performed with nitric acid, the maximum yield of nitrated hydrolysis lignin (83–101 %) was achieved using 1,4-dioxane, acetonitrile, and tetrahydrofuran; and the maximum nitrogen content (4.3–4.5 %) was achieved using 1,4-dioxane or acetonitrile. The use of dimethyl sulfoxide and dimethylformamide leads to a decrease in the product yield to 23–35 %, to a lower nitrogen content of 1.3–3.9 % and an increased oxygen content, which indicates the occurrence of not only nitration, but also depolymerization and oxidative transformations. When nitration with acetyl nitrate, the reaction takes place for 1–3 min, herewith the product contains up to 4.7 % of nitrogen. On the IR spectra of nitrated hydrolysis lignins, new absorption bands appear at 1555 and 1710 cm–1 due to the appearance of carboxyl and nitro groups.

CONDUCTANCE OF AMMONIUM NITRATE IN WATER – NITRIC ACID – NITROGEN PENTOXIDE MIXTURES AT VARIOUS TEMPERATURES

1951 ◽  
Vol 29 (6) ◽  
pp. 452-460 ◽  
Author(s):  
Edward G. Taylor ◽  
Charles A. N. Baker ◽  
L. Murray Lyne
Keyword(s):  
Thermal Stability ◽  
Nitric Acid ◽  
Ammonium Nitrate ◽  
Salt Concentration ◽  
Specific Conductance ◽  
Considerable Degree ◽  
Nitrogen Pentoxide ◽  
All Solutions ◽  
Wide Range

Conductance measurements have been made with ammonium nitrate in water – nitric acid – nitrogen pentoxide mixtures at various temperatures and over a wide range of concentrations. For all solutions except those rich in nitrogen pentoxide the variation of the specific conductance with the concentration of ammonium nitrate is similar to that observed for many electrolytes in a variety of solvents. With nitrogen-pentoxide-rich solvents however the specific conductance of ammonium nitrate is observed to decrease with increasing salt concentration. This is regarded as indicative of an interaction between the salt and one or more of the components of the nitric acid – nitrogen pentoxide system. The variation of conductance with temperature is normal in all cases. It is shown that ammonium nitrate confers a considerable degree of thermal stability on anhydrous nitric acid.

Sign in / Sign up

Export Citation Format

Share Document