Sodium Sulfide → HCID 18400155, compound

Participants

Reaction Steps

2,4-Dinitro-3-ethyl-6-methylaniline (see Example 2) is treated with sodium sulfide to afford 1,2-diamino-3-ethyl-6-methyl-4-nitrobenzene. Treatment with cyanogen bromide affords to 2-amino-4-ethyl-7-methyl-5-nitrobenzimidazole. This is converted to 2-diazo-4-ethyl-7-methyl-5-nitrobenzimidazole tetrafuoroborate with sodium nitrite and tetrafluoroboric acid. Thermal decomposition of the diazonium salt gives 4-ethyl-2-fluoro-7-methyl-5-nitrobenzimidazole. Conversion to 4-ethyl-2-fluoro-5-(2-imidazolinylamino)benzimidazole is completed according to Scheme 5.

Provenance & Evidence