62802-42-0

Colorless to light yellow liquid

2-Chloro-5-fluoropyrimidine is used to prepare 2,4-disubstituted-5-fluoropyrimidine , which is a biologically active molecule seen in anticancer agents like 5-fluorouracil.

Synthesis of 2-chloro-5-fluoropyrimidine: add 2,4-Dichloro-5-fluoropyrimidine and reducing metal powder to the solvent, stir to raise the temperature to the reaction temperature, slowly add acid dropwise, and keep the temperature until the reaction is completed Finish. Filtration, phase separation or direct evaporation of the solvent, and distillation under reduced pressure to remove the solvent to obtain 2-chloro-5-fluoropyrimidine.

Step A: Synthesis of 2-chloro-5-fluoropyrimidine To 2,4-dichloro-5-fluoropyrimidine (15.0 g, 89.8 mmol) was added tetrahydrofuran (100 mL) and zinc powder (17.6 g, 269 mmol). The reaction mixture was heated to 70 °C with vigorous stirring, followed by the slow dropwise addition of acetic acid (5.14 mL, 89.8 mmol) over a period of 1 hour. After completion of the dropwise addition, the reaction mixture was heated to reflux for 5 hours. Upon completion of the reaction, the reaction mixture was diluted with dichloromethane and filtered through a diatomaceous earth pad to remove solid impurities. The filtrate was concentrated under reduced pressure and purified by silica gel column chromatography to afford the target product 2-chloro-5-fluoropyrimidine (6.00 g, 50% yield).

[1] A. Dunaiskis. “LARGE SCALE SYNTHESIS OF 2-CHLORO-5-FLUOROPYRIMIDINE.” Organic Preparations and Procedures International 27 1 (1995): 600–602.
[2] A. DUNAISKIS. “ChemInform Abstract: Large Scale Synthesis of 2-Chloro-5-fluoropyrimidine.” ChemInform 26 52 (1995).