N-[4-(1,3-benzodioxol-5-yl)-1-benzyl-3-(2-hydroxyethoxy)-1H-pyrazol-5-yl]-4-(tert-butyl)benzenesulfonamide → N-[4-(1,3-benzodioxol-5-yl)-3-(2-hydroxyethoxy)-1H-pyrazol-5-yl]4-(tert-butyl)benzenesulfonamide

Participants

Reaction Steps

N-[4-(1,3-benzodioxol-5-yl)-1-benzyl-3-(2-hydroxyethoxy)-1H-pyrazol-5-yl]-4-(tert-butyl)benzenesulfonamide (Example 78) (15.8 g) was dissolved in acetic acid (500 ml). Under an atmosphere of nitrogen, Pearlmann's catalyst (JM type 91, 1.6 g) was added and the reaction was stirred for 48 h under 4 bars of hydrogen at 50° C. The reaction mixture was filtered on a short pad of Celite® and concentrated under reduced pressure. To the oily residue was added water (300 ml) and dichloromethane (300 ml). The phases were separated, the organic phase washed with a 5% aqueous solution of sodium bicarbonate (2×150 ml), dried over sodium sulfate and concentrated under reduced pressure. The residue was dissolved in methanol (300 ml), solid potassium carbonate (8 g) was added in one portion and the reaction mixture was stirred overnight and then concentrated under reduced pressure. Water (500 ml) was added to the resulting solid and the mixture as extracted with dichloromethane (3×500 ml). The organic fraction was dried on sodium sulfate and concentrated under reduced pressure. The red-yellow solid was re-crystallised in ethyl acetate yielding the title compound as a white solid (7.2 g)

Provenance & Evidence