Product name：Methanone, (4-chlorophenyl)(1-fluorocyclopropyl)- (9CI)
Product use：Basic raw materials, organic intermediates, pharmaceutical intermediates
The synthesis process is as follows:
potassium fluoride; water; toluene; diethylene glycol;
Reactants are commercially availlable.
Bayer Aktiengesellschaft, US5434303, A1, (1995) c) Preparation of 1-fluoro-cyclopropyl 4-chlorophenyl ketone, of the formula STR17 which is required as starting material. 2000 g (34.5 mol) of potassium fluoride are introduced into 7 liters of diet hylene glycol, and the mixture is treated with 500 ml of toluene at room temperature. The toluene i s distilled off at 150°C., and the mixture is then allowed to cool to 100°C., and 1500 g (5 mol) o f 4-chloro-phenyl 1-bromo-3-chloro-n-propyl ketone are added in portions in the course of 15 minutes . The reaction mixture is heated for 4 hours at 150°C. and then cooled and poured into 10 liters o f water. The resulting mixture is extracted five times with 2 liters of toluene per extraction, and the combined organic phases are washed with water, dried over magnesium sulphate and concentrated by stripping off the solvent under reduced pressure. The residue which remains is distilled under a high vacuum, and the distillate collected is subjected to fractional distillation under a high vacuum, using a spinning band column. In this manner, 100 g (10percent of theory) of 1-fluorocyclopropyl 4- chlorophenyl ketone are obtained in the form of a liquid of boiling point 70°-76°C. at 0.03 mbar. 1 9 F NMR (188 MHz, CDCl3 /CFCl3): delta=191.7 ppm 1 H NMR (200 MHz, CDCl3 /TMS): delta=1.39-1.62 ppm (m, 4H, cyclopropyl-H), 7.44 and 7.96 ppm (AA'BB' system, 4H arom. H).