Water → 3-(5-Hexenyl)-1-methyluracil

A mixture of sodium hydride (86 mg, 3.6 mmol) and 1-methyluracil (500 mg, 4 mmol) in dimethyl sulfoxide (25 ml) was stirred for 15 minutes, and then 6-bromo-1-hexene (647 mg, 4 mmol) was added. After stirring for 20 hours, the reaction mixture was poured into water (50 ml) and extracted with 20% ethanol-dichloromethane (3×50 ml). The combined organic layers were washed with saturated aqueous sodium chloride solution (20 ml) and dried over sodium sulfate. The solvent was evaporated under vacuum to give a residue which was purified by column chromatography (silica, ethyl acetate) to give 3-(5-hexenyl)-1-methyluracil (598 mg, 72% yield).