Hydrochloric Acid → 1-tert-Butyl-1H-pyrazole

Participants

Reaction Steps

A mixture of 1,1,3,3-tetramethoxypropane (37 g, 226 mmol), tert-butyl-hydrazine hydrochloride (28 g, 226 mmol) and conc HCl (60 mL, 720 mmol) in EtOH (300 mL) was heated at reflux overnight. The mixture was poured into water and the resulting mixture was extracted with ether. The combined organics were washed with brine, dried (MgSO4) and concentrated in vacuo to give 1-tert-butyl-1H-pyrazole (25 g, 89% yield). 1H NMR (400 MHz, DMSO-d6): δ7.73 (s, 1 H), 7.38 (s, 1 H), 6.17 (s, 1 H), 1.47 (s, 9 H); MS (ESI) m/z: 125.1 [M+H]+.

Provenance & Evidence