反应详情

To a stirred solution of 4′-methyl-5-(5-trifluoromethyl-tetrazol-1-yl)-biphenyl-3-carboxylic acid methyl ester (3.7 mmol, 1.34 g) in 50 ml of THF was added a solution of LiOH.H2O (18.5 mmol, 776.3 mg) in 12 mL of water. The reaction mixture was heated to reflux for 3.5 hours, then cooled to room temperature. Solvent was removed under reduced pressure, and the pH of the liquid residue was adjusted to 2.0 by addition of 2N aqueous HCl solution. The mixture was extracted with ethyl acetate and the combined ethyl acetate layers were dried over anhydrous Na2SO4 and concentrated in vacuo to give 4′-methyl-5-(5-trifluoromethyl-tetrazol-1-yl)-biphenyl-3-carboxylic acid as light yellow solid (1.25 g, 97% yield).

1. temperatureThe reaction mixture was heated
2. temperatureto reflux for 3.5 hours
3. customSolvent was removed under reduced pressure
4. additionthe pH of the liquid residue was adjusted to 2.0 by addition of 2N aqueous HCl solution
5. extractionThe mixture was extracted with ethyl acetate
6. dry with materialthe combined ethyl acetate layers were dried over anhydrous Na2SO4
7. concentrationconcentrated in vacuo