Magnesium → 5-Amino-1-(4-fluorophenyl)-4-[3-(2-tert-butyldimethylsiloxyethyl)benzoyl]pyrazole

Into an oven dried flask containing magnesium turnings (0.386 g, 15.9 mmol) and tetrahydrofuran (10 ml) was added 3-(2-tert-butyldimethylsiloxyethyl)bromobenzene (5.0 g, 15.9 mmol) and the reaction mixture was heated at reflux. After 3 h, the reaction mixture was cooled to room temperature and 5-amino-1-(4-fluorophenyl)-4-(2-pyridylthiocarboxy)pyrazole (2.37 g, 7.6 mmol) was added and the stirring was continued for 16 h. The reaction mixture was concentrated in vacuo. The residue was dissolved in ethyl acetate and washed with aqueous ammonium chloride and brine and dried over sodium sulfate. The organics were removed in vacuo and the residue was purified by flash chromatography (elution gradient: 10-30% ethyl acetate/hexane) to give 5-amino-1-(4-fluorophenyl)-4-[3-(2-tert-butyldimethylsiloxyethyl)benzoyl]pyrazole (1.20 g).

1. customInto an oven dried flask
2. temperaturethe reaction mixture was heated
3. temperatureat reflux
4. waitthe stirring was continued for 16 h
5. concentrationThe reaction mixture was concentrated in vacuo
6. dissolutionThe residue was dissolved in ethyl acetate
7. washwashed with aqueous ammonium chloride and brine
8. dry with materialdried over sodium sulfate
9. customThe organics were removed in vacuo
10. customthe residue was purified by flash chromatography (elution gradient: 10-30% ethyl acetate/hexane)

ORD record

ord-5a505cf3240a4d159af2e7c71b6bba65

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06376527B1