Formaldehyde → (2-(2-bromo-5-fluorophenyl)-2H-1,2,4-triazol-3-yl)methanol
Reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([F:8])=[CH:4][C:3]=1[N:9]1[CH:13]=[N:12][CH:11]=[N:10]1.[CH2:14]=[O:15]>>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([F:8])=[CH:4][C:3]=1[N:9]1[C:13]([CH2:14][OH:15])=[N:12][CH:11]=[N:10]1Participants
Conditions
- Temperature
- 150 °C
Procedure
A suspension of 1-(2-bromo-5-fluorophenyl)-1H-1,2,4-triazole (3.63 g, 15 mmol) in 37% formaline (15 mL) in a sealed vessel was stirred in an oil bath heated at 150° C. for 9.5 h. After cooling, the mixture was extracted with CH2Cl2 (15 mL×2) and the combined extracts were washed with brine, dried (Na2SO4), filtered and concentrated. The residual crude oil was purified by column chromatography (SiO2, 0-7% MeOH/CH2C12) followed by trituration with Et2O to obtain 430 mg of the title compound as white crystalline solid: TLC Rf 0.5 (10% MeOH/CH2Cl2); HPLC rt=1.31 min; LC/MS m/z 272/274 (M+H); 1H NMR (CDCl3, 500 MHz) δ ppm 3.67 (1H, br.s, OH), 4.65 (2H, s, 9-OCH2), 7.13-7.22 (1H, m, 5-CH), 7.29 (1H, dd, J=8, 3 Hz, 3-CH), 7.71 (1H, dd, J=9.0, 5.3 Hz, 6-CH), 8.03 (1H, s, 8-CH); 13C NMR (CDCl3, 125.8 Hz) δ ppm 55.3 (9-OCH2), 116.2 (d, J=3.9 Hz, 1-C), 117.4 (d, J=25 Hz, 3-CH), 119.4 (d, J=22 Hz, 5-CH), 134.7 (d, J=8.3 Hz, 6-CH), 137.0 (d, J=10 Hz, 2-C), 151.3 (8-CH), 156.3 (7-C), 161.8 (d, J=252 Hz, 4-CF); HRMS (ESI) calcd for C9H8BrN3O (M+H) 271.9835; found 271.9828 (δ-2.5 ppm).
Workup
- temperatureAfter cooling
- extractionthe mixture was extracted with CH2Cl2 (15 mL×2)
- washthe combined extracts were washed with brine
- dry with materialdried (Na2SO4)
- filtrationfiltered
- concentrationconcentrated
- customThe residual crude oil was purified by column chromatography (SiO2, 0-7% MeOH/CH2C12)
Sources & evidence
- ORD record
- ord-71cdaede09304e91a026e95f218466c7
- Source dataset
- uspto-grants-2009_02
- Patent number
- US07491819B1
Reaction notes
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