On March 31, 1994, Suzuki, Hitomi; Mori, Tadashi published an article.Quality Control of 2-Chloro-4-methyl-1-nitrobenzene The title of the article was Ozone-mediated nitration of chloro- and bromobenzenes and some methyl derivatives with nitrogen dioxide. High ortho-directing trends of the chlorine and bromine substituents. And the article contained the following:
In the presence of ozone, chloro- and bromobenzenes are nitrated smoothly with nitrogen dioxide at low temperatures, giving a mixture of the corresponding nitro derivatives in nearly quant. yield. The nitration products are generally ortho-rich as compared with those obtained by the conventional procedures based on the use of HNO3 or mixed acid. The ortho:para isomer ratios of the products can be reversed from ortho-rich (o:p = 1.14 and 1.09) to para-predominant (o:p = 0.45 and 0.68) simply by altering the initial concentration of the substrate. This enigmatic phenomenon was interpreted in terms of the equilibrium between the monomer and the dimer forms of the cation radical derived from a halobenzene and the difference in their relative reactivity toward nitrogen dioxide. Similar preference for substitution ortho to the halogen substituent was observed with 4-chloro- and 4-bromotoluenes, which concurrently suffer extensive ipso attack by the present reagent system, giving 4-methyl-2-nitrophenol as a common side product. The experimental process involved the reaction of 2-Chloro-4-methyl-1-nitrobenzene(cas: 38939-88-7).Quality Control of 2-Chloro-4-methyl-1-nitrobenzene
The Article related to regioselective nitration halobenzene, nitrogen dioxide ozone mediated nitration, solvent effect nitration halobenzene, Benzene, Its Derivatives, and Condensed Benzenoid Compounds: Nitro and Nitroso Compounds and other aspects.Quality Control of 2-Chloro-4-methyl-1-nitrobenzene
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics