GENERAL METHODS: 3-Chlorobenzoylacetonitrile (1.0 mmol) and PIDA (2.2 mmol) were dissolved in ethanol (8 mL), and the reaction was stirred under reflux conditions for 0.5 hours. The reaction process was monitored by thin layer chromatography (TLC). After completion of the reaction, the reaction mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent ratio 20:1 petroleum ether/ethyl acetate) to afford the target product ethyl 3-chlorobenzoylformate. Note: The solvent used in this synthesis step is methanol (MeOH).
