Reaction #2028893

Reaction equation

aldehyde

4-[4-formyl-5-phenyl-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide

sodium borohydride

→

desired product

Yield 46.0%

4-[4-hydroxymethyl-5-phenyl-3-(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide

Yield 46.0%

Solvents

methanol

Conditions

Workup

1. 1
   OtherThe reaction was quenched with the addition of an aqueous 1M KHSO4 solution (3 mL)
2. 2
   ExtractionThe mixture was extracted with dichloromethane
3. 3
   Otherthe organic solution dried
4. 4
   Concentrationconcentrated
5. 5
   OtherThe residue was chromatographed on silica (1:1 hexane:ethyl acetate)

Procedure

To a solution of the aldehyde prepared in Step 2 (165 mg, 0.41 mmol) in methanol (3.5 mL) at 0° C. was added sodium borohydride (16 mg, 0.41 mmol). The reaction solution was kept at 0° C. for 2.5 hours. The reaction was quenched with the addition of an aqueous 1M KHSO4 solution (3 mL). The mixture was extracted with dichloromethane and the organic solution dried and concentrated. The residue was chromatographed on silica (1:1 hexane:ethyl acetate) to give the desired product (36 mg, 46%): m.p. 179°-180° C.; 1H NMR d 7.91 (m, 2H), 7.53-7.40 (m, 5H), 6.75 (s, 2H), 4.53 (d, 2h, J=5.0 Hz), 4.30 (t, 1H, J=5.0 Hz).

Source