Isopropyl iodide → 4-Iodo-1-(propan-2-yl)-1H-pyrazole

To a slurry of sodium hydride (95%, 0.58 g, 23 mmol) in DMF (20 mL) was added a solution of 4-Iodo-1H-pyrazole (2023A) (4.07 g, 21 mmol) in DMF (20 mL) and the resulting mixture was stirred at rt for 10 min. Then 2-iodopropane (2.52 mL, 25.2 mmol) was added dropwise and the resulting mixture was stirred at rt overnight. The reaction mixture was concentrated, diluted with ethyl acetate, washed with water (4 times), brine, dried and concentrated to give an oily residue which was chromatographed (SiO2, 10%-20% ethyl acetate/hexane) to give 4-Iodo-1-isopropyl-1H-pyrazole 2023B (3.27 g, 66%). HPLC-MS tR=1.66 min (UV254 nm); mass calculated for formula C6H9IN2 235.98, observed LCMS m/z 237.0 (M+H).

1. stirringthe resulting mixture was stirred at rt overnight
2. concentrationThe reaction mixture was concentrated
3. additiondiluted with ethyl acetate
4. washwashed with water (4 times), brine
5. customdried
6. concentrationconcentrated
7. customto give an oily residue which
8. customwas chromatographed (SiO2, 10%-20% ethyl acetate/hexane)

ORD record

ord-0e228e79404c4ec3899b5a1d1ae6ee4e

Source dataset

uspto-grants-2009_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07504424B2