To a degassed solution of tert-butyl 4-hydroxynaphthalen-1-ylcarbamate (13.3 g, 51.3 mmol) and DBU (12.6 mL, 51.3 mmol) in MeCN (80 mL) under nitrogen was added 2,4-dichloropyrimidine (7.65 g, 51.3 mmol) in acetonitrile (19 mL) and the reaction mixture was heated to reflux for 4 hr. The solvent was evaporated in vacuo and the residue was taken up into DCM (100 mL) and was washed with water (2×100 mL) and brine (100 mL), then dried (MgSO4) and evaporated in vacuo. The residue was purified by flash column chromatography (SiO2, 330 g, EtOAc in isohexane, 0-50%, gradient elution) to afford the title compound as a pale pink solid (6.80 g, 34%); Rt 2.50 min (Method 2); m/z 372/374 (M+H)+, (ES+)+.
