Cornforth reagent → 5-Acetyl-4-tert-butyl-3-(4-methylphenyl)sulfonyloxypyrazole

Participants

Reaction Steps

4-tert-Butyl-5-(1-hydroxyethyl)-3-(4-methylphenyl)sulfonyloxypyrazole (3.8 g, 11.3 mmol) was dissolved in dichloromethane (100 ml) and PDC (4.26 g, 11.3 mmol) was added After stirring at ambient temperature for 2 h, the reaction mixture was poured directly onto a silica gel column and eluted with dichloromethane then 20% ethyl acetate/dichloromethane to give the required product (2.71 g) as a white solid. 1H NMR (360 MHz, CDCl3) δ 1.26 (9H, s), 2.46 (3H, s), 2.56 (3H, s), 7.36 (2H, d, J=8.2 Hz), 7.82 (2H, d, J=8.2 Hz), 10.70 (1H, br s); MS (ES+) m/e 337 [MH]+.

Provenance & Evidence