Amino acids 3 : 6-dinitrobenzoates

Dinitrobenzoates. The following experimental details are for glycine (aminoacetic acid) and may be easily adapted for any other amino acid. Dissolve 0-75 g. of glycine in 20 ml. of N sodium hydroxide solution and add 2 32 g. of finely powdered 3 5-dinitrobenzoyl chloride. Shake the mixture vigorously in a stoppered test-tube the acid chloride soon dissolves. Continue the shaking for 2 minutes, filter (if necessary) and acidify with dilute hydrochloric acid to Congo red. Recrystallise the derivative immediately from water or 50 per cent, alcohol. 

Before chromatography, unstable or volatile solutes must be converted to appropriate derivatives, e.g., alcohols to 3,5-dinitrobenzoates. Derivatives may be easier to detect, separate or identify than the parent compounds, e.g., fluorescent dansyl derivatives of amino acids. 

Dinitrotoluene is oxidized to 2,4-dinitrobenzoic acid [610-30-0] by potassium permanganate or chromic acid, and is reduced to 2,4-diaminotoluene by iron and acetic acid. It is reduced partially by zinc chloride and hydrochloric acid to 2-amino-4-nitrotoluene [99-55-8] and by ammonium sulfide to 4-amino-2-nitrotoluene [119-32-4],... 

Amino-3-methylphenol, see 4-Nitrophenol Aminomethylphosphonic acid, see Glvnhosate 2 -Amino-2-naphthoxypropiophenone, see Napropamide 4-Amino-2-naphthoxypropiophenone, see Napropamide Aminonitrobenzoic acid, 3.4-Dinitrobenzoic acid 4-Amino-4 -nitrobiphenyl, see Benzidine 2-Amino-6-nitro-lV-(l-ethylpropyl)-3,4-xylidine, see... 

The synthesis of TATB (14) from the reaction of 2,3,4,5,6-pentanitroaniline (31) with ammonia has been reported. " In one route, 2,3,4,5,6-pentanitroaniline (31) is synthesized from the nitration of 3,5-dinitroaniline (30) " the latter is obtained from the selective reduction of TNB ° or via a Schmidt reaction with 3,5-dinitrobenzoic acid. Another route to 2,3,4,5,6-pentanitroaniline (31) involves the selective reduction of TNT (1) with hydrogen sulfide in ammonia followed by nitration of the resulting 4-amino-2,6-dinitrotoluene (46), during which the methyl group is lost by oxidation-decarboxylation. 

Amino-4,6-dinitrotoluene crysts 175-176, 173-174 (307) 3 5 2,4,6-TNT 2-methyl-3,5-dinitrobenzoic acid >180... 

Crystals of stoichiometric 1 1 mixtures of compounds that can complex with each other have been shown to form preferentially to pure crystals of the individual components. In some cases these crystals may have potential non-linear optical properties. An interesting example is the 1 1 mixture of p-aminobenzoic acid and 3,5-dinitrobenzoic acid. (15) A view of the crystal structure is shown in figure 3. Examination of this figure leads one to the hypothesis that the preference for the mixed crystal may be due to a) a more stable H-bonding interaction between the different benzoic acids in the hetero-dimer than in the homo-dimer b) the ability of the mixed crystal (hetero- dimers) to H-bond between their amino and nitro groups. It is likely that both of these factors play a role in the stability of the crystal structure. Calculational modelling can aid in determining the importance of these factors. 

By implication, the H-bonding within the dimer seems to be of some importance. The accuracy of this predic-tion was tested by mixing 3,5-dinitrobenzoic acid with p-dimethylaminobenzoic acid to see if a 1 1 crystalline material formed. In this case, H-bonding between the nitro and amino groups is precluded by the methylation of the amino groups. Apparently, a stoichiometric mixed solid does form (as evidenced by an unmistakable change in color to red), although the structure has not yet been determined. 

In the non-target analysis of this sample, carried out by LC-NMR and LC-MS, TNT-typical biodegradation products such as 2-amino-4,6-dinitro-toluene and 4-amino-2,6-dinitrotoluene were detected, although smaller quantities of 2-amino-4,6-dinitrobenzoic acid, trinitrobenzene and 2,2/6,6/-tet-ranitro-4,4/-azoxytoluene could also be identified. The NMR chromatogram further reveals that the soil was also contaminated by PAHs. Several late-eluting compounds could be identified as PAHs. 

Aromatic dinitro compounds may be selectively reduced by hydrazine in the presence of transition metal catalysts.136 Pitre and Lorenzotti obtained 3-amino-5-nitrobenzoic acid in 82% yield by treating 3,5-dinitrobenzoic acid with Raney Ni and an appropriate amount (3.6 equiv) of hydrazine in water (eq. 9.57).137 Similarly, 2,4-dinitrophe-nol and 2,4-dinitroaniline were reduced to 2-amino-4-nitrophenol and 2-amino-4-nitroaniline, respectively, with 10% Pd-C and hydrazine in ethanol solution. 

Urinary excretion of these metabolites peaked near the end of the work shift but declined to low or undetectable concentrations by the start of work the following day. The calculated elimination half-lives of total dinitrotoluene-related material detected in urine ranged from 1.0 to 2.7 h and those of individual metabolites from 0.8 to 4.5 h. Urinary excretion in Fischer 344 rats given 2,6-DNT accounted for half of the dose (10 mg kg 72 h after administration of [ " C]-2,6-DNT. 2,6-Dinitrobenzoic acid, 2,6-dinitrobenzyl alcohol glucuronide, and 2-amino-6-nitrobenzoic acid accounted for 95% of the urinary Fecal excretion accounted for one-fifth of the dose in 72 h. 

An aq. soln. of 3,5-dinitrobenzoic acid and 3.6 moles hydrazine hydrate treated with Raney-Ni, allowed to stand overnight, then refluxed 7-8 hrs. until gas evolution ceases 3-amino-5-nitrobenzoic acid. Y 71%. F. e. with 10%-Pd-on-carbon instead of Raney-Ni s. D. Pitre and E. Lorenzotti, Ghimia 19, 462 (1965). 

The halogen in an aromatic compound (e.g., 4-chloro-3,5-dinitrobenzoic acid) can be made to react with amino group (e.g., p-aminobenzoic acid) in solid state at 180° C to give the corresponding amine (Scheme 21). 

Among other nitro compounds used for the reaction, 2,4-dinitro-phenol (58), 3,5-dinitrosalicylic acid (reduced to 3-amino-5-nitrosalicylic acid) (59, 60), 4,6-dinitroguaiacol (61), sodium-l-nitroanthraquinone-5-sul-fonate (62), 3,5-dinitrophthalic acid (63), 3,4-dinitrobenzoic acid (64, 65), and m-dinitrobenzene (66) should be mentioned. 

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