反应详情

A solution of 17.4 g (0.075 mol.) of 3,4 dinitrobenzoylchloride in 250 ml of methylene chloride is treated at 0°-20° C. with a solution of 13 g. (0.15 mol.) of morpholine in 100 ml. of methylene chloride. The solution is kept at 20°-25° C. for 2 hrs., the solvent is evaporated and the residue triturated with water. Recrystallization from methanol affords 4-morpholinocarbonyl-1,2-dinitrobenzene (m.p. 136°-137° C.). 17.0 G. of 4-morpholinocarbonyl-1,2-dinitrobenzene in 340 ml. of methanol is hydrogenated for 3 hrs. at 45-50 psi in the presence of 1.7 g. of 5% palladized charcoal. The resulting solution of 1,2-diamino-4-morpholinocarbonylbenzene is filtered and concentrated to ~170 ml. 14.0 G. of 1,3-bis-methoxycarbonyl-S-methyl isothiourea, 170 ml. of water and 4 ml. of acetic acid are added to the diamine solution and the mixture is refluxed for 3 hrs. The solution is concentrated and cooled. Filtration and recrystallization from methanol-chloroform affords 5(6)-morpholinocarbonyl-2-carbomethoxyaminobenzimidazole (m.p. 224° C. dec.).

1. custom, the solvent is evaporated
2. customthe residue triturated with water
3. customRecrystallization from methanol