The general procedure for synthesizing methyl 3-oxovalerate from propionyl chloride was as follows: in a mixed solvent of 520 mL of methylene chloride and 30 mL of methyl ethyl ketone, 116 g (1.0 mol) of methyl acetoacetate, 77.8 g (1.05 mol) of calcium hydroxide, and 106.5 g (1.15 mol) of propionyl chloride were added, and the reaction conditions were the same as those in Example 1. After completion of the reaction, the pH of the reaction mixture was adjusted with ammonia to 9.1. 117 g of methyl 3-oxovalerate was finally obtained, which was analyzed by gas chromatography (GC) with a purity of 79.0% and a yield of 71.0%.
