Abstract
Hydrogenation of a mixture of ortho -
and para -dinitro derivatives of 1,4-dimethoxybenzene
in ethyl acetate under palladium catalysis, allows 3,6-dimethoxybenzene-1,2-diamine
to be isolated as the sole product; this diamine is then converted
into 4,7-dimethoxy-2-methyl-1H -benzimidazole,
a building block for the preparation of imidazobenzo(hydro)quinones.
Key words
benzimidazoles - diamines - heterocycles - hydroquinones - reduction
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