To a solution of tert-butyl [3-(cyclopropylamino)phenyl]carbamate (5.51 g, 15.4 mmol) in tetrahydrofuran (100 mL) were added N-ethyl-N-isopropylpropane-2-amine (8.06 mL, 46.2 mmol) and 2-chloro-5-nitropyrimidin-4-yl thiocyanate (6.66 g, 30.7 mmol), and the mixture was stirred at room temperature for 1 hr. To the reaction mixture was added water (100 mL), and the mixture was extracted with ethyl acetate (2×50 mL). The combined organic layer was washed with saturated brine (30 mL), and filtered through a silica gel pad. The obtained filtrate was concentrated under reduced pressure to give tert-butyl {3-[cyclopropyl(5-nitro-4-thiocyanatopyrimidin-2-yl)amino]phenyl}carbamate as a brown amorphous solid. The obtained compound was used for the next reaction without further purification.
