1.3.5- trichlorobenzene, nitration

It was first prepd in 1923 by Turek on treating 2,4,6-trichloro-l,3,5-trinitrobenzene with an alkali azide in ale, acet or w soln. It can be obtained also from aniline by chlorination to sym-trichloro-aniline, followed by diazotization, treatment with ale to give sym-trichlorobenzene, nitration with mixed nitric-sulfuric acid to trinitrotrichloro-benzene and finally treatment with an ale soln of Na azide(Refs 3,5,6a 8)... 

The observation of nitration in nitromethane fully dependent on the first power of the concentration of aromatic was made later. The rate of reaction of /)-dichlorobenzene ([aromatic] = 0-2 mol [HNO3] = 8-5 mol 1 ) obeyed such a law. The fact that in a similar solution 1,2,4-trichlorobenzene underwent reaction according to the same kinetic law, but about ten times slower, shows that under first-order conditions the rate of reaction depends on the reactivity of the compound. 

Fig. 5 Main contamination sources identified by PCA for sediments, fish, and suface water in the Ebro River basin, and explained variances for each principal component. Variable identification. Organic compounds in sediments 1, summatory of hexachlorocyclohexanes (HCHs) 2, summa-tory of DDTs (DDTs) 3, hexachlorobenzene (HCB) 4, hexachlorobutadiene (HCBu) 5, summatory of trichlorobenzenes (TCBs) 6, naphthalene 7, fluoranthene 8, benzo(a)pyrene 9, benzo(b) fluoranthene 10, benzo(g,h,i)perylene 11, benzo(k)fluoranthene 12, indene(l,2,3-cd)pyrene. Organic compounds in fish 1, hexachlorobenzene (HCB) 2, summatory of hexachlorocyclohexanes (HCHs) 3, o,p-DDD 4, o,p-DDE 5, o,p-DDT 6, p,p-DDD 7, />,/>DDE 8, />,/>DDT 9, summatory of DDTs (DDTs) 10, summatory of trichlorobenzenes (TCBs) 11, hexachlorobutadiene (HCBu) 12, fish length. Physico-chemical parameters in water 1, alkalinity 2, chlorides 3, cyanides 4, total coliforms 5, conductivity at 20°C 6, biological oxygen demand 7, chemical oxygen demand 8, fluorides 9, suspended matter 10, total ammonium 11, nitrates 12, dissolved oxygen 13, phosphates 14, sulfates 15, water temperature 16, air temperature...

All reported syntheses of TATB to date involve the nitration of substrates containing leaving groups which are subsequently replaced by amino groups. The current industrial synthesis of TATB (14) involves the nitration of 1,3,5-trichlorobenzene (33) to 1,3,5-trichloro-2,4,6-trinitrobenzene (34) followed by reaction with ammonia in toluene under pressure. Both nitration and amination steps require forced conditions with elevated temperatures. 

Trichlorobenzene, Nitric acid. Sulfuric acid Sulfuric acid. Sodium nitrate, Meta-nitroanUine Sulfuric acid. Nitric acid, Meta-nitroanUine Isocyanogen tetrabromide. Acetone, Sodium azide Nitric acid. Sulfuric acid, N,N-Dimethylaniline DimethylanUine, Sulfuric acid. Nitric acid... 

As a starting material for the preparation of sym-trinitrotriazidobenzene, 1,3,5-trichlorobenzene is used. It is obtained by the chlorination of aniline and the removal of the amino group. Nitration to the trinitro derivative is described in Vol. I. The final reaction is simple powdered 1,3,5,-trichloro-2,4,6-trinitrobenzene is added to an aqueous alcohol solution of sodium azide. The precipitated product is washed with alcohol and water and dried at a moderate temperature. The product so obtained may be purified by crystallization from chloroform. 

Trichloro-2,4,6-trinitrobenzene is prepared by the nitration of trichlorobenzene with a mixture of nitric acid and sulfuric acid. 1,3,5-Trichloro-2,4,6-trinitrobenzene is then converted to l,3,5-trinitro-2,4,6-triaminobenzene (TATB) by nitrating with ammonia as shown in Reaction 7.4. The yellow-brown crystals of TATB are filtered and washed with water. 

Laboratory. The preferred lab prepn consists of the nitration of s-trichlorobenzene with a mixt of nitric acid and oleum at a temp of... 

In acetic acid the rates of nitration of chlorobenzene and bromo-benzene were fairly close to being first order in the concentration of aromatic, and nitration fully according to a first-order law was observed with o-, m-, and/(-dichlorobenzene, ethyl benzoate and 1,2,4-trichlorobenzene. 

Trichloro-2,4,6-trinitrobenzene (m. p. 187°C) can be prepared by the nitration of 1,3,5-trichlorobenzene with anhydrous nitric acid and oleum (Jackson and Wing [42]). However, according to van Ryn [43] the yield is poor. 

The reactor is charged with 980 kg of 30% oleum to which 100 kg of solid trichlorobenzene is added during the course of one hour. The whole is heated to 100°C for another hour and kept at this temperature for 2-3 hr longer with constant stirring. Towards the end of this operation sulphonation takes place. The reaction may be considered complete when a sample of the mixture taken from the nitrator dissolves completely in water. 

TATB is obtained by nitration of trichlorobenzene and conversion of the trinitrotrichlorobenzene to TATB. 

Summary TCTNB is prepared by reacting trichlorobenzene with a nitrating acid mixture composed of nitric and sulfuric acids. The resulting product is then filtered, washed with water, dried, and then recrystallized from benzene. Commercial Industrial note Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

Going from one of the most sensitive of the aromatic explosives to one of the very least sensitive, we have TATB (Figure 3.18). This is a new, very insensitive, high explosive that is finding broad use in nuclear weapons development. The extreme degree of insensitiveness boosts the safety in handling and in accident situations, which is so crucial in that particular application. It is made by direct nitration of 1,3,5-trichlorobenzene to 1,3,5-trichloro-2,4,6-trinitrobenzene. This, in turn, is then converted to the 1,3,5-triamino- by amine substitution of the three chlorine atoms. 

Ineluded in this sequence are reactions such as the hydration of ethylene oxide to mono-, di-, and triethylene glycol, chlorination of benzene to mono-, di-, and trichlorobenzene (similarly with nitration), etc. Since we are going to consider these as elementary steps, order corresponds to stoichiometry and the rate constants follow the Arrhenius law. 

The starting substance, l,3,5-trichloro-2,4,6-trinitrobenzene, can be prepared from 1,3,5-trichlorobenzene by nitration in a strong nitration mixture such as oleum/nitric acid at high temperatures [153, 154, 159, 160]. TATNB can also be prepared by nitration of 1,3,5-triazido-2,4-dinitrobenzene [155]. 

The first challenge to be overcome in the production of PBO is the high purity synthesis of the monomer 4,6-diamino-l,3-benzenediol dihydrochloride (DABDO) (Scheme 9.6). The long-established method developed by Wolfe et al. [46] involved reacting diacetyl-1,3-benzenediol with concentrated nitric acid containing less than 2% water. This method required multiple recrystallizations to remove undesirable byproducts. The expense of the starting materials and the purification process has lead to the abandonment of this method of DABDO production in favor of a process developed by Lysenko [47] at the Dow Chemical Company. This method involves nitrating 1,2,3-trichlorobenzene under acid conditions to produce l,2,3-trichloro-4,6-dinitrobenzene. Sodium hydroxide is... 

The preferred method of preparation in the laboratory consists of the nitration of s-trichlorobenzene with a mixture of nitric acid and oleum at a temperature of 150°C for three hours. A toluene solution of the trinitrotrichlorobenzene (TCTNB) produced by the nitration is then aminated to yield TATB. The preferred manufacturing method to produce a particle size greater than 20 microns in 96 percent of the yield, suitable for PBXs and normal explosive compounds, is by the partially patented procedure that follows. The procedure is carried out in two steps a nitration step and an amination. 

The bis-HCl salt is easily oxidized also, but can be handled. The tetrafunctional monomer for PBO is prepared from resorcinol diacetate by nitration and hydrogenation. Care must be taken in view of explosive side products. A detailed description appeared recently. A probably more economical synthesis of 4,6-diaminoresorcinol has become available by nitration of 1,2,3-trichlorobenzene followed by alkaline hydrolysis and hydrogenation. The status of the work aimed at a commercial process for cis-PBO was reviewed recently.Diaminohydroquinone, the precursor for trans-PBO, can be prepared from chloranil by ammonolysis followed by hydrogenation ... 

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