Trinitrobenzenes

In the nitration of benzene, wj-dinilro- and sym-trinitrobenzenes are obtained under more vigorous conditions. With naphthalene, 1-nitronaphthalene is the first product and further nitration gives a mixture of 1,5- and 1,8-dinitronaphthalenes 2-nitronaphthalene is never obtained. 

Unlike aliphatic hydrocarbons, aromatic hydrocarbons can be sul-phonated and nitrated they also form characteristic molecular compounds with picric acid, styphnic acid and 1 3 5-trinitrobenzene. Many of the reactions of aromatic hydrocarbons will be evident from the following discussion of crystalline derivatives suitable for their characterisation. 

Dissolve equimolecular quantities of the hydrocarbon and 1 3 5 trinitrobenzene in hot alcohol, benzene or glacial acetic acid, and allow to cool. Filter oflf the solid which separates and recrystallise it from one of these solvents. 

Dinitrodipbenyl 4 4 -Dinitrodipbenyl 1 3 6-Trinitrobenzene 2 4 6-Trinitrotoliiene o- N itrochlorobenzene m-Nitrocblorobeiizeiie p-Nitrocblorobenzene... 

Trinitrobenzene may be prepared by heating the sodium salt of 2 4 6-trinitrobenzoio acid with water ... 

Trinitrobenzene, 1,3,5-trinitrobenzene (indicator) dissolve 0.1 g in 100 mL alcohol pH range colorless 11.5-14.0 orange. 

Aromatic hydrocarbons can be purified as their picrates using the procedures described for amines. Instead of picric acid, 1,3,5-trinitrobenzene or 2,4,7-trinitrofluorenone can also be used. In all these cases, following recrystallisation, the hydrocarbon can be isolated either as described for amines or by passing a solution of the adduct through an activated alumina column and eluting with toluene or petroleum ether. The picric acid and nitro compounds are more strongly adsorbed on the column. 

Benzo[ghi]perylene (1,12-benzoperylene) [191-24-2] M 276,3, m 273°, 277-278.5°, 278-280°, Purified as light green crystals by recrystn from CfiH6 or xylene and sublimes at 320-340° and 0.05mm [UV Helv Chim Acta 42 2315 7959 Chem Ber 65 846 1932 Fluoresc. Spectrum J Chem Soc 3875 7954]. 1,3,5-Trinitrobenzene complex m 310-313° (deep red crystals from C6Hg) picrate m 267-270° (dark red crystals from CgH6) styphnate (2,4,6-trinitroresorcinol complex) m 234° (wine red crystals from CgH6). It recrystallises from propan-l-ol [J Chem Soc 466 7959]. 

Benzo[e]pyrene (1,2-benzpyrene) [192-97-2] M 252.3, m 178-179 , 178-180 . Purified by passage through an AI2O3 column (Woelm, basic, activity I) and eluted with CgHg and recrystd from 2 volumes of EtOH- CeHe (4 1). Forms colourless or light yellow prisms or needles. [J Chem Soc 3659 1954 Justus Liebigs Ann Chem 705 190 1967.] 1,3,5-Trinitrobenzene complex m 253-254° (orange needles from... 

Trinitrobenzene [99-35-4] M 213.1, m 122-123 . Crystd from glacial acetic acid, CHCI3, CCI4, EtOH aq EtOH or EtOH/ benzene, after (optionally) heating with dil HNO3. Air dried. Fused, and crystd under vacuum. 

Trinitrobenzene reacts with dry acetone in the presence of potassium methoxide to give a crystalline violet compound CgHsN OjK. Deduce its identity from the C NMR spectra 18. Conditions ( 03)280, 25 °C, 22.63 MHz. (a) //broadband decoupled spectrum (b) without decoupling (c) expanded section of (b). 

TRINITROBENZENE TRINITROBENZENESULFONIC ACID TRINITROBENZOIC ACID TRINITROCHLOROBENZENE TRINITROFLUORENONE... 

A crystalline addition product of indole with picryl chloride (i.e. l-chloro-2,4,6-trinitrobenzene), together with an unidentified amorphous substance, were obtained by the action of picryl chloride on indole magnesium iodide, and analogous products were obtained in the reaction between the indole Grignard reagent and 1-chloro-2,4,5-trinitrobenzene. 

Highly electron-deficient 1,3,6-trinitrobenzene (145) treated with phenyl acet-amidines 146 in ethanol provided low yields of a dinitroindole derivatives, probably 4,6-dinitroindoles 148 (77JOC435). Formation of indole derivatives 148 can be explained by nucleophilic substitution of the activated aromatic hydrogen leading to intermediates 147, which then cyclized to the final products 148 (Scheme 22). 

A novel indole ring formation involving DBU nucleophilic addition to 1,3,5-trinitrobenzene has appeared as shovm in Eq. 10.69. 

Current views (100) on the mechanism of bromination by NBS invoke the formation of molecular bromine and bromine atoms in low concentration, which subsequently act as the brominating agent. The bromination reaction was studied in detail in this laboratory under a variety of conditions using 93 (R = Ms) as a model. The product 94 (R = Ms) was indeed formed (42%) when NBS was substituted by 1.1 equivalents of bromine which was added at a slow rate to the reaction mixture. The yield was 68% when benzoyl peroxide was used as a catalyst. Using NBS alone or in the presence of reagents such as barium carbonate, pyridine, or s-trinitrobenzene, the yield was 60-70%. 

XONIUM COMPODNDS, TRIETHYLOXO-NroM E LUO BOR ATE, 46,113 0XONIUM COMPOUNDS, TRIMFTHYLOXO-NIUM PLUOBORATE, 46,120 0XONIUM COMPOUNDS, TRIMETHYLOXO-NIUM 2,4,6 TRINITROBENZENE-SULEONATE, 46, 122... 

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