Potassium Hydroxide → [3-(5-Chloro-2-thienyl)-4-(2-methoxyethyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl]acetic acid

Of the compound from Example 169A, 3.2 g (9.25 mmol) were dissolved in 28 ml of methanol. Then 2.82 ml of 20% strength aqueous potassium hydroxide solution were added. The mixture was stirred at RT for 2 h. The methanol fraction was reduced to half on a rotary evaporator. The mixture was then diluted with water and extracted once with 15 ml of ethyl acetate. The aqueous phase was acidified with 920 μl of concentrated hydrochloric acid and extracted with twice 15 ml of ethyl acetate. The combined organic phases were dried over sodium sulphate, filtered and freed from the solvent on a rotary evaporator. Drying in an HV gave 2.34 g (80% of theory) of the title compound.

1. customThe methanol fraction was reduced to half on a rotary evaporator
2. additionThe mixture was then diluted with water
3. extractionextracted once with 15 ml of ethyl acetate
4. extractionextracted with twice 15 ml of ethyl acetate
5. dry with materialThe combined organic phases were dried over sodium sulphate
6. filtrationfiltered
7. customfreed from the solvent on a rotary evaporator
8. customDrying in an HV

ORD record

ord-e3d82ff195314e8c89c409279653e80b

Source dataset

uspto-grants-2012_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08202895B2