Triethylsilane → 4-benzyl-1-ethyl-5-(4-methoxyphenoxy)-3-methyl-1H-pyrazole

Participants

Reaction Steps

A solution containing 54 mg of [1-ethyl-5-(4-methoxyphenoxy)-3-methyl-1H-pyrazol-4-yl]-phenyl-methanol and 28 μl of triethylsilane in 2 ml of trifluoroacetic acid was stirred at room temperature for 22 h. The mixture was concentrated and saturated sodium hydrogen carbonate (6 ml) was added. The mixture was extracted three times with 8 ml of dichloromethane. The combined extracts were dried over magnesium sulphate, filtered and evaporated. The residue was purified by flash chromatography on silica gel using ethyl acetate/petroleum ether (bp 40-60° C.) (1:4) for the elution to give 33 mg of 4-benzyl-1-ethyl-5-(4-methoxyphenoxy)-3-methyl-1H-pyrazole as a yellow oil. Mass spectrum (ES) m/z 323 [M+H]+, 364 [M+H+CH3CN]+. 1H NMR (DMSO-d6) 1.19 (t, 3H), 2.00 (s, 3H), 3.46 (s, 2H), 3.70 (s, 3H), 3.80 (q, 2H), 6.82-6.89 (m, 4H), 7.01 (d, 2H), 7.12 (t, 1H), 7.20 (t, 2H).

Provenance & Evidence