Triethylamine → 3-Dimethylaminophenyl isocyanate

Participants

Reaction Steps

3-Dimethylaminobenzoic acid (1.65 g), diphenylphosphoryl azide (2.16 ml) and triethylamine (1.4 ml) were dissolved in tetrahydrofuran (20 ml), and the reaction mixture was kept at 60° C. for 1 hour to give 3-dimethylaminophenyl isocyanate. The reaction mixture was cooled to 0° C. Triethylamine (4.2 ml) and 3-aminomethyl-4-(3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl)-5-methyl[1,2,4]triazole di-p-toluenesulfonate (7.42 g) were added, and the mixture was stirred for 2 hours. The reaction mixture was concentrated. The residue was partitioned between ethyl acetate and water. The organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution and saturated brine, and dried over magnesium sulfate. The solvent was evaporated. The obtained residue was purified by silica gel column chromatography using a mixed solvent of ethyl acetate and methanol (10:1) as an eluent and by silica gel column chromatography using a mixed solvent of chloroform and methanol (50:1) as an eluent, and crystallized from ethyl acetate to give 140 mg of N-((4-(3-(2-chlorobenzoyl)-5-ethylthiophen-2-yl)-5-methyl[1,2,4]triazol-3-yl)methyl)-N'-(3-dimethylaminophenyl)urea.

Provenance & Evidence