7-Bromo-2-chlorothieno[3,2-d]pyrimidine (200 mg, 0.81 mmol) was dissolved in 2-butanol (4 mL) and then potassium carbonate (223 mg, 1.61 mmol) and 3,4,5-trimethoxybenzenamine (110 mg, 0.81 mmol) were added. After blowing nitrogen to the reaction mixture for 10 minutes, Pd2(dba)3 (50 mg, 0.048 mmol) and Xphos (35 mg, 0.073 mmol) were added. The reaction mixture was stirred at 80° C. for 2.5 hours and then filtered with celite. The filtrate was diluted with ethyl acetate and washed with brine. The organic layer was dried with magnesium sulfate, filtered with celite, and then concentrated. Purification by chromatography (15% ethyl acetate/hexane) yielded the target compound (120 mg, 43% yield).
