Formic Acid → 4-Methylbenzimidazole

Reaction equation

[NH2:1][C:2]1[C:7]([NH2:8])=[CH:6][CH:5]=[CH:4][C:3]=1[CH3:9].Cl.[OH-].[NH4+].[CH:13](O)=O>>[CH3:9][C:3]1[C:2]2[N:1]=[CH:13][NH:8][C:7]=2[CH:6]=[CH:5][CH:4]=1

Participants

Reactant 4

HCID 284Formic Acid

HCID 313Hydrochloric Acid

HCID 14923Ammonium Hydroxide

HCID 175932,3-Diaminotoluene

Product 1

HCID 15193414-Methylbenzimidazole

Procedure

To a flask were added 2.0 g 2,3-diaminotoluene, 1.0 g 90% formic acid and 30 ml 5M hydrochloric acid and the mixture was heated to 90 C under nitrogen for 4 hours. After cooling to 22 C, the mixture was basified with aqueous ammonium hydroxide and the product was removed by filtration and washed with water. The product was purified by column chromatography using pure ethyl acetate resulting in 1.0 g brown solid.