1.3.5- Trinitrobenzene, reduction

Phloroglucinol (1,3,5-Trihydroxy benzene, 1,3,5-Trioxy-benzol in Ger). C6H3(OH)3,mw 126.11, white to yellowish crysts mp 200—209° when heated slowly 212—217° when heated rapidly bp, sublimes with decompn. SI sol in w, sol in ale and eth. Combustible. Can be prepd by fusion of resorcinol with caustic soda, or by reduction of trinitrobenzene. It is highly toxic. by ingestion, inhalation and skin absorption, and is a strong irritant to skin and mucous membranes Refs 1) Beil 6,1092, (545) [1075]... 

TACOM TBA TCLP THC TNB TNBA TNT TOC TRBP TW-SCWO Tank-Automotive and Armaments Command tributylamine toxicity characteristic leaching procedure total hydrocarbons trinitrobenzene trinitrobenzoic acid trinitrotoluene (an energetic material) total organic carbon thermal reduction batch processor transpiring-wall supercritical water oxidation... 

A synthesis of hexanitrobenzene (55) has been reported which involves hydroxyamino oxidation. Although no experimental details of this procedure are given the synthesis is reported to start from partial reduction of 1,3,5-trinitrobenzene (2) to l,3,5-tris(hydroxyamino)benzene... 

Some nitro derivatives of benzofurazan have been investigated for their explosive properties. 4-Amino-5,7-dinitrobenzofurazan (56) has been prepared by a number of routes including (1) the thermally induced cyclodehydration of l,3-diamino-2,4,6-trinitrobenzene (55), (2) the nitration of 4-amino-7-nitrobenzofurazan and (3) the reduction of 4-amino-5,7-dinitrobenzofuroxan with triphenylphoshine. The isomeric 5-amino-4,7-dinitrobenzofurazan (57) has been prepared along similar routes. ... 

Dinitroaniline is usually obtained from 1,3,5-trinitrobenzene by reduction of a nitro group with sodium hydrosulphide. It may be used as starting material for the preparation of pentanitroaniline. 

To obtain higher nitrated azoxybenzenes, indirect nitration methods must be applied. 3,5,3 ,5 -Tetranitroazoxybenzene (VII), for example, may be prepared from sym-trinitrobenzene either by boiling with a dilute sodium carbonate solution (Lobry de Bruyn and Leent [12]) or by partial reduction (Blanksma [13]). 

Trinitrobenzene is formed by of decarboxylation of trinitrobenzoic acid. It can also be prepared from trinitrochlorobenzene by reduction with copper in alcohol. Further nitration of dinitrobenzene also yields trinitrobenzene, but the reaction must be carried out under very severe conditions (high S03-concentration in the mixed acid, high nitration temperature), and the yields are low. 

A partial reduction of the aromatic ring of trinitrobenzene was recently described by Ohno. Yamamoto and Oka [160]. By acting with 1,4-dihydronico-tinic acid derivatives, 13,5-trinitrobenzene was reduced to dihydrotrinitro-benzene at room temperature in dry acetonitryl in the atmosphere of argon and away from light. 

Derivation By fusion of resorcinol with caustic soda, by reduction of trinitrobenzene. 

Primary nitroaromatics are TNT the environmental breakdown products, including 1,3,5-trinitrobenzene (TNB), 1,3-dinitrobenzene (DNB), 2,4-and 2,6-dinitro-toluene (DNTs) and the primary reduction products 2-amino 4,6-dinitrotoluene and 4-amino 2,6-dinitrotoluene (ADNTs). Nitramines include RDX and octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine (HMX). Additional energetic compounds discussed in this chapter include nitroglycerin, white phosphorus, and ammonium perchlorate. Other energetic compounds are not discussed due to a lack of information regarding toxicity to wildlife species. 

Other complex metal hydrides can only rarely be applied to reduction of C=C bonds. Sodium borohydride, which can be used in aqueous-alcoholic solution, seems not normally to attack ethylenic bonds. A few cases only of partial reduction of cyclic iminum salts96 and of selective reduction of unusually activated ethylenic bonds97 have been reported. However, some polynitro aromatic compounds, e.g., 1,3,5-trinitrobenzene, can be converted in high yield with saturation of the aromatic system into nitrocyclohexanes or nitro-cyclohexenes.98 Sodium hydridotrimethoxyborate has proved valuable as a mild reducing agent for preparation of a series of nitroparaffins from nitro-alkenes."... 

Figure 3 shows a cychc voltammogram for compound 3H at a low-scan rate (see footnote 1). In all cases, starting with a cathodic scan, no reduction waves appear in the first scan, so neither l-chloro-2,4,6-trinitrobenzene (the Sn product), nor 1,3,5-trinitrobenzene (the Sn product), are initially present in the reaction mixtures. Figure 3a shows that, upon starting with an anodic scan, two well-defined waves at 0.68 V and 1.24 V are observed. When the anodic scan is followed by a cathodic scan, two waves, at 0.53 V and 0.56 V, are observed. These reduction waves correspond to l-chloro-2,4,6-trinitrobenzene (the Sn product) and 1,3,5-trinitrobenzene (the Sn product), respectively [23, 40]. 

When the anodic scan is reversed after the first oxidation wave (0.68 V) (Fig. 3b) only one reduction wave is obtained ( 0.53 V). Thus, the oxidation wave at 1.24 V appears to be connected with the reduction wave at —0.56 V. That, is to say, l-chloro-2,4,6-trinitrobenzene is obtained due to the oxidation of 3H (1,3) (o -cotnplex, the reaction), while 1,3,5-trinitrobenzene is derived from the oxidation of 3H (1,1) (o -complex, the reaction). 

Scheme 12 General electrochemical mechanism for the synthesis of l-butyl-2,4,6-trinitrobenzene derivatives. 88114 acts as both nucleophile and reducting agent...

A solution of 1,3,5-trinitrobenzene in N-methylformamide was subjected to electrolysis at —0.70 V (Path A, Scheme 18). The controlled-potential electrolysis was stopped after a passage of one electron per each molecule. The formed anion-radical species of 1,3,5-trinitrobenzene were allowed to react with N-methyl-formamide. Under the used experimental conditions the o -complexes were the only species present in the reaction mixtures. Exhaustive oxidative controlled-potential electrolysis at 1.30 V gave A-methyl-iV-(2,4,6-trinitrophenyl)formamide (Sn product) in good yield (80%). Without a preliminary reductive electrolysis (Path B, Scheme 18), the same type of o -complexes proved to be formed, and after exhaustive oxidative controlled-potential electrolysis at 1.30 V, A-methyl-iV-(2,4,6-trinitrophenyl)formamide (Sn product) was obtained in 20% yield. 

Commercially available serum albumins (whether Cohn fraction V or crystalline BSA) contain variable and inconsistent amounts of free fatty acids (0.08-2.4 mol/mol albumin). These fatty acids are entirely (99%) removed by charcoal defatting (Chen, 1967). Differences in free fatty acids in serum albumin have been attributed to variations in the levels of free fatty acids in plasma. Analysis of free fatty acids in human serum (Saifer et aL, 1961) showed a complex composition of 43 different fatty acids, 26 of which were identified. Eight fatty acids—namely oleic, palmitic, linoleic, arachidonic, palmitoleic, myristic, linolenic, and stearic acids—constituted 90% of the total. A similar fatty acid distribution was shown in BSA (Fuller-Noel and Hunter, 1972). The presence of fatty acids in BSA imparts a conformational stability to the molecule, which assumes a more compact conformation as shown by a decreased reactivity of amino groups with fluorodinitrobenzene (Green, 1963) or with trinitrobenzene sulfonic acid (Andersson et aL, 1971) and a decrease in the availability of the disulfide bonds to reduction with j3-mercaptoetha-... 

The mechanism was assumed to involve an organocopper intermediate. The solvent plays an important role. In xylene, the simple reduction, yielding trinitrobenzene, and a reduction-oxidation process giving picric acid increase substan-tially.200 Aryl triflates (Eq. 46), and to a lesser extent tosylates, afford biaryls by treatment with zinc in the presence of nickel chloride and iodide ions. Ol... 

Some synthetically important radical reactions have been studied by API-MS methods. The transient radicals were unambiguously detected and characterized by MS/MS methods. Hess and coworkers [39] reported the degradation products resulting from modified Fenton reactions with the nitroaromatic compounds trinitrotoluene (TNT) and trinitrobenzene (TNB) through electrospray ionization tandem mass spectrometry (off-line ESI-MS"). Several hydroperoxide adducts were tentatively identified as initial, one-electron reduction products of TNT, and their stmcture was confirmed by tandem mass spectrometry (Scheme 5.1). 

Azo-compounds are the most numerous class of pyrrole nitrogen derivatives. The a-compounds have been stated to be less stable to air and light than the jS-compounds, but this is certainly not generally true . Azocompounds seem to be more basic than the parent pyrroles, and in some cases to be markedly acidic neither of these facts is difficult to understand if the structures of the cations (p. 76) and anions are considered. The ability of many a-compounds to couple a second time, as with diazotized /)-nitroani-line, is the basis of a colour test for distinguishing them from j8-compounds. Azopyrroles give picrates, styphnates, picrolonates and trinitrobenzene complexes, but the usefulness of some of these is limited by their lacking true melting points /. The reduction of azo compounds was mentioned above. 

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