Triethylsilane → 4-benzyl-1-ethyl-5-(4-methoxyphenoxy)-3-methyl-1H-pyrazole
Reaction equation
[CH2:1]([N:3]1[C:7]([O:8][C:9]2[CH:14]=[CH:13][C:12]([O:15][CH3:16])=[CH:11][CH:10]=2)=[C:6]([CH:17]([C:19]2[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=2)O)[C:5]([CH3:25])=[N:4]1)[CH3:2].C([SiH](CC)CC)C>FC(F)(F)C(O)=O>[CH2:17]([C:6]1[C:5]([CH3:25])=[N:4][N:3]([CH2:1][CH3:2])[C:7]=1[O:8][C:9]1[CH:10]=[CH:11][C:12]([O:15][CH3:16])=[CH:13][CH:14]=1)[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1Participants
Procedure
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).
Workup
- concentrationThe mixture was concentrated
- additionsaturated sodium hydrogen carbonate (6 ml) was added
- extractionThe mixture was extracted three times with 8 ml of dichloromethane
- dry with materialThe combined extracts were dried over magnesium sulphate
- filtrationfiltered
- customevaporated
- customThe residue was purified by flash chromatography on silica gel
- washfor the elution
Sources & evidence
- ORD record
- ord-134b508dfcef47dba57a0eaa3789c728
- Source dataset
- uspto-grants-2004_03
- Patent number
- US06699887B2
Reaction notes
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