反应详情

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).

1. concentrationThe mixture was concentrated
2. additionsaturated sodium hydrogen carbonate (6 ml) was added
3. extractionThe mixture was extracted three times with 8 ml of dichloromethane
4. dry with materialThe combined extracts were dried over magnesium sulphate
5. filtrationfiltered
6. customevaporated
7. customThe residue was purified by flash chromatography on silica gel
8. washfor the elution