反应详情

温度

0 °C

Add methanol (3 mL), tetrahydrofuran (3 mL), and water (2 mL) to a flask containing methyl 5-(4H-1,2,4-triazol-3-yl)pentanoate (0.5 g; 1.0 equiv; 2.73 mmoles). Add lithium hydroxide (0.261 g; 4.0 equiv; 10.92 mmoles) in one portion, and stir at room temperature for 90 minutes. Cool the solution to 0° C. and add 5N hydrogen chloride (2.18 mL; 4.0 equiv; 10.92 mmoles) slowly. Concentrate the mixture and then azeotrope the residue with toluene (4×10 mL). Add dichloromethane (30 mL) followed by magnesium sulfate. Filter, and rinse the filter cake with 100 mL 10% ethanol in dichloromethane. Concentrate to provide 5-(4H-1,2,4-triazol-3-yl)pentanoic acid (1.6 g; >100%) as an alcoholic adduct: MS (m/z): 170 (M+1).

1. concentrationConcentrate the mixture
2. filtrationFilter
3. washrinse the filter cake with 100 mL 10% ethanol in dichloromethane
4. concentrationConcentrate