反应详情

After suspending N1,4-dimethyl-5-cyano-2-ethoxybenzamide (92 g) in acetonitrile (11), tert-butyl dicarbonate (110 g) and dimethylaminopyridine (2.6 g) were added and the mixture was stirred at room temperature overnight. The reaction mixture was heated to 90° C. and stirred for 3 hours. tert-Butyl dicarbonate (110 g) was further added and the mixture was stirred at 50° C. overnight. After cooling to room temperature, the precipitated crystals were filtered off (24.3 g). The filtrate was concentrated and the residue was purified by silica gel column chromatography (solvent: n-hexane-ethyl acetate) to yield the title compound (81.1 g) as a white solid.

1. additionwere added
2. temperatureThe reaction mixture was heated to 90° C.
3. stirringstirred for 3 hours
4. stirringthe mixture was stirred at 50° C. overnight
5. temperatureAfter cooling to room temperature
6. filtrationthe precipitated crystals were filtered off (24.3 g)
7. concentrationThe filtrate was concentrated
8. customthe residue was purified by silica gel column chromatography (solvent: n-hexane-ethyl acetate)