反应详情

4,5-Dimethoxy-1,2-dinitrobenzene was hydrogenated to the diamino compound according to general operating instructions 1, and said compound was cyclized with trimethyl orthobenzoate to 5,6-dimethoxy-2-phenyl-1H-benzimidazole (flash point 131-133° C.) as crude product according to general operating instructions 3. This benzimidazole derivative was reacted with 4-methylphenylboronic acid to 5,6-dimethoxy-1-(4-methylphenyl)-2-phenyl-1H-benzimidazole (flash point 145-148° C.) according to general operating instructions 14. After ether cleavage with hydrobromic acid according to general operating instructions 6 to 5,6-dihydroxy-1-(4-methylphenyl)-2-phenyl-1H-benzimidazole (1H-NMR of hydrobromide (D6-DMSO): δ=2.42 ppm s (3H); 6.68 s (1H); 7.22 s (1H); 7.40-7.62 m (10H)), it was alkylated with 6-bromohexanoic acid isopropyl ester according to general operating instructions 8. 6-[[5-Hydroxy-1-(4-methylphenyl)-2-phenyl-1H-benzimidazol-6-yl]oxy]hexanoic acid isopropyl ester