Chloronitrobenzene production figures

The reaction of aniline and aniline derivatives with p-chloronitrobenzene is the critical coupling reaction practiced by Bayer and Monsanto for the manufacture of 4-nitrodiphenylamine, 2. Hydrogenation of 2 produces 4-aminodiphenylamine (4-ADPA), 3, which is a key intermediate in the p-phenylenediamine class of antioxidant used in rubber products (Figure 8). 

Nucleophilic aromatic substitution occurs only if the aromatic ring has an electron-withdrawing substituent in a position ortho or para to the leaving group. The more such substituents there are, the faster the reaction. As shown in Figure 16.18, only ortho and para electron-withdrawing substituents stabilize the anion intermediate through resonance a meta substituent offers no such resonance stabilization. Thus, p-ch oronitrobenzene and o-chloronitrobenzene react with hydroxide ion at 130 °C to yield substitution products, but m-chloronitrobenzene is inert to OH-. 

Where does the hydrogen atom in the product of hydro-de-diazoniation, 2-chloro-nitrobenzene (8.66), come from in CH3OD It was found (Bunnett and Takayama, 1968 b Broxton and Bunnett, 1979) that in the reaction of Scheme 8-47 the deuterium content of 2-chloronitrobenzene was 79%, a figure which is not close to either zero or 100%. For other substituted benzenediazonium ions a very wide range of D incorporation was observed. This range is consistent with hydro-de-diazoniation by both homolytic and a competitive anionic mechanism. The anionic pathway is favored by an increase in methoxide ion concentration. 

Figure 7.1 Reduction of 3-chloronitrobenzene in 5-mM aqueous hydrogen sulfide containing Hyde County natural organic matter (66 mg c L ) at pH 7.2 and 25°C. (a) Plot of concentration at time t, C, in relation to initial concentration, Co, indicating pseudo-first-order kinetics. The blank indicates no reaction in the absence of the organic matter. (6) Disappearance of the chloronitrobenzene, and appearance of reaction products, 3-chlorophenyUiydroxylamine, and 3-chloroaniUne. [Reproduced with permission from F. M. Dunnivant, R. P. Schwarzenbach, and D. L. Macalady, Environ. Sci. Technol. 26, 2133 (1992). Copyright 1992, American Chemical Society.]...

Production of o- and p-chloronitrobenzene in West Germany is around 60,000 tpa in the USA some 40,000 tpa are produced they are very versatile intermediates (Figure 5.45). 

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