Carbon Dioxide → 5-Methylbenzimidazol-2-one

Participants

Reaction Conditions

Reaction Steps

24.4 g (0.2 mol) of 3,4-diaminotoluene, 18 g of water and 5.5 g (0.04 mol) of potassium carbonate were introduced into a 200 ml reactor. After sealing, CO2 was injected up to a pressure of 35 bar. The mixture was then heated to 230° C., and this temperature maintained for 12 hours. During the heating period, the pressure rose to up to 80 bar. After the reaction was completed, the mixture was cooled, the excess CO2 pressure was let down, and the aqueous slurry of crystals was removed. The aqueous catalyst solution was separated off through a filter, the solid was washed with water until it no longer contained carbonate, and was dried. 27.7 g (93.7% of theory) of 5-methylbenzimidazolone of m.p. = 301-303° C. were isolated.

Provenance & Evidence