To a solution of the above 5-chloro-2,4-dichloropyrimidine (73 mg, 0.4 mmol) in EtOH (2 mL) were added tert-butyl trans-4-aminomethylcyclohexylcarbamate (100 mg, 0.44 mmol) and DIPEA (77 μL, 0.44 mmol). The reaction mixture was heated at 40° C. for 1 h. The reaction mixture was concentrated in vacuo and the resulting residue was diluted with EtOAc. The solution was washed with brine. The aqueous layer was re-extracted with EtOAc (×2). The combined organic phase was dried over anhydrous Na2SO4 and concentrated in vacuo to yield 148 mg (99%) of {4-[(2,5-dichloro-pyrimidin-4-ylamino)-methyl]-cyclohexyl}-carbamic acid tert-butyl ester.
