4-Chloro-3-fluorobenzaldehyde

The reaction was carried out in an 80 mL Teflon-lined stainless steel reactor equipped with a magnetic stir bar. 4-Chloro-3-fluoroiodobenzene (1.0 mmol), rhodium(III) chloride hydrate (0.025 mmol), PPh3 (0.1 mmol), Et3N (1.2 mmol), and N,N-dimethylacetamide (2 mL) were added to the reactor in a glove box. The autoclave was tightened. CO and H2 were injected into the autoclave to bring the total pressure to 10 bar (1:1). The mixture was transferred to an oil bath preheated at 90°C for 12 hours. The reaction was controlled using a Haake-D3 temperature controller. After the reaction was complete, the reactor was cooled in ice water. The atmosphere was carefully vented.

Add 5 mL of CH₂Cl₂ to the reaction mixture. Add 10 mL of deionized water to the mixture and extract five times with the solvent N,N-dimethylacetamide. Dry the organic layer with anhydrous Na₂SO₄. Concentrate the organic layer by rotary evaporation. Purify the product by silica gel column chromatography using n-hexane/ethyl acetate as eluent.

white to light yellow crystal powder

4-Chloro-3-fluorobenzaldehyde is an organic intermediate that can be prepared from 4-chloro-3-fluoroiodobenzene in one step. It has been reported in the literature that it can be used to prepare piperidine derivatives.