Methoxy Trinitroanisol

Trinitroanisol may also be prepared by the interaction of methyl iodide and silver picrate, and by the nitration of anisic acid, during which the carboxyl group is lost, but the most convenient method appears to be that of Jackson70 and his collaborators by which a methoxy group is substituted for chlorine in a nucleus already nitrated. A methyl alcohol solution of picryl... 

Since the methoxy group exercises a greater effect in promoting substitution than the chlorine Atom does, it is to be expected that dinitroanisol would take on a third nitro group more easily than dinitrochlorobenzene (to form picryl chloride), and with less expense for acid and for heat. The reactions indicated below are probably the best for the large-scale commercial production of trinitroanisol. 

Trinitroanisole was first obtained by Cahours [2a] by the direct nitration of anisole. The reaction proceeds very vigorously, as file presence of a methoxy group greatly facilitates the introduction of nitro groups and some highly coloured by-products are formed [20]. For this reason it is preferable to prepare trinitroanisole via chlo-rodinitrobenzene (p. 547). 

Methoxy-3,5-dinitropyridine and MeO gives, as the stable adduct (32), the T,3-complex relative to the MeO group, and not the 1,1-complex (33) that is expected by analogy with 2,4,6-trinitroanisole. ... 

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