Synthesis of 3,6-Dimethoxybenzene-1,2-diamine and of 4,7-Dimethoxy-2-methyl-1H-benzimidazole

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.

benzimidazoles - diamines - heterocycles - hydroquinones - reduction

References

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