Cesium carbonate (3.1308 g, 9.6089 mmol) was added to a mixture of 6-bromoquinazolin-2-ol (1.0812 g, 4.8044 mmol) in tert-butyl alcohol (15 mL, 160 mmol), toluene (25 mL, 230 mmol) and 2-butanone (10 mL, 100 mmol). The mixture was heated at 110° C. for 1 hour in a sealed tube then cooled to room temperature and methanesulfonic acid 4-tert-butyl-cyclohexyl ester (2.2519 g, 9.6089 mmol) was added. The reaction was then heated at 110° C. overnight. The reaction mixture was cooled to room temperature then filtered through a pad of celite. The filtrate was concentrated under reduced pressure, adsorbed onto silica gel and purified by flash chromatography (80 g SiO2 column; 0-40% EtOAc in heptane eluent) to give the title compound in 20% yield. ESI-MS (M+H+): 365.1
