Isopropyl iodide → 3-Iodo-1-isopropyl-1H-pyrazole

Participants

Reaction Steps

3-iodo-1H-pyrazole (250 mg, 1.29 mmol) was added as a solution in DMF (0.8 mL) to a 1.0 M THF solution of NaHMDS (1.5 mL, 1.5 mmol) that had been pre-cooled in an ice water bath. Additional portions of DMF (2×0.35 mL) were used to ensure complete transfer. 2-iodopropane was added in one portion and the reaction mixture was allowed to warm to r.t. After 3.5 h, the reaction mixture was diluted with saturated aqueous NH4Cl (5 mL), water (20 mL), and EtOAc (20 mL). The phases were separated, and the aqueous phase was extracted with EtOAc (20 mL). The combined organic phase was dried over Na2SO4, filtered, and concentrated to afford a crude residue that was purified by silica gel chromatography to provide 3-iodo-1-isopropyl-1H-pyrazole (4.02). LCMS-ESI+ (m/z): [M+H]+ calcd for C6H10IN2: 236.99; found: 236.94.

Provenance & Evidence