2-Chloro-5-trifluoromethylbenzaldehyde

Chemical Properties

Colorless liquid

Uses

2-Chloro-5-(trifluoromethyl)benzaldehyde may be used as reactant in the three-component reaction of 2-halogenated aromatic aldehydes, 1H-benzo[d]imidazol-5-amine and cyclohexane-1,3-diones to afford imidazoquinolinoacridinone derivatives. It may be used in the gas-phase chemical derivatization of poly(tetrafluoroethylene) and poly(ethylene terephthalate) using gas plasma.

Synthesis

General procedure for the synthesis of 2-chloro-5-trifluoromethylbenzaldehyde from 2-chloro-5-trifluoromethylbenzyl alcohol: 2-chloro-5-trifluoromethylbenzyl alcohol (5.0 mmol), copper acetate (Cu(OAc)2, 9.1 mg, 0.05 mmol), and 2,2,6,6-tetramethylpiperidinium-1-oxyl radical (TEMPO, 7.8 mg, 0.05 mmol ) in a solvent mixture of acetonitrile (CH3CN, 5 mL) and water (H2O, 10 mL) was stirred at room temperature for the reaction. The reaction process was monitored by thin-layer chromatography (TLC) and the eluent was petroleum ether/ethyl acetate (4:1). After completion of the reaction, dichloromethane (10 mL) was added to the reaction mixture for extraction. The organic phase was separated and the aqueous phase was extracted twice more with dichloromethane (10 mL x 2). All organic phases were combined, dried with anhydrous sodium sulfate and concentrated under reduced pressure to obtain the crude product. The crude product was purified by column chromatography with the eluent of petroleum ether/ethyl acetate (10:1) to obtain the target product 2-chloro-5-trifluoromethylbenzaldehyde.

References

[1] Tetrahedron Letters, 2014, vol. 55, # 10, p. 1677 - 1681
[2] Collection of Czechoslovak Chemical Communications, 1982, vol. 47, # 3, p. 967 - 983