A solution of 8-bromo-3-methyl-2-(methylthio)quinazolin-4(3H)-one (500 mg, 1.753 mmol), tributyl(1-ethoxyvinyl)stannane (Synthonix, Wake Forest, N.C.; 0.652 mL, 1.929 mmol), and Pd(PPh3)4 (81 mg, 0.070 mmol) in toluene (9.0 mL) was stirred under argon at 100° C. for 19 h, then at 110° C. for 1 d. The reaction was cooled to 25° C. and concentrated onto silica gel. Chromatographic purification (silica gel, 0-50% EtOAc/Hexanes) furnished 8-acetyl-3-methyl-2-(methylthio)quinazolin-4(3H)-one (128.7 mg, 0.518 mmol, 30% yield) as a white solid: m/z (ESI, +ve) 249.2 (M+H)+. 8-(1-ethoxyvinyl)-3-methyl-2-(methylthio)quinazolin-4(3H)-one (35.5 mg, 0.128 mmol, 7% yield) as a colorless oil: m/z (ESI, +ve) 277.1 (M+H)+.
