Ammonium Chloride → 3-benzyloxy-1-methyl-1H-pyrazol-4-ylacetonitrile

Temperature

-78 °C

To a mixture of potassium t-butoxide (2.24 g) and dimethoxyethane (10 ml) was added a solution of p-toluenesulfonylmethyl isocyanide (2.05 g) in dimethoxyethane (10 ml) and the mixture was stirred at −78° C. for 5 min. Then a solution of 3-benzyloxy-1-methyl-1H-pyrazole-4-carbaldehyde (2.16 g) in dimethoxyethane (10 ml) was added. After stirring at said temperature for 1 hr, the mixture was stirred for 1 hr. while raising the temperature to room temperature. To the obtained mixture was added methanol (380 ml), and the mixture was refluxed for 1 hr. After cooling, the reaction solution was poured into saturated aqueous ammonium chloride solution and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried (MgSO4) and concentrated. The residue was subjected to silica gel column chromatography, and 3-benzyloxy-1-methyl-1H-pyrazol-4-ylacetonitrile (1.86 g, yield 82%) was obtained as a colorless oil from a fraction eluted with ethyl acetate-hexane (1:2, volume ratio).

1. stirringAfter stirring
2. customfor 1 hr
3. stirringthe mixture was stirred for 1 hr
4. temperaturewhile raising the temperature to room temperature
5. temperaturethe mixture was refluxed for 1 hr
6. temperatureAfter cooling
7. extractionthe mixture was extracted with ethyl acetate
8. washThe ethyl acetate layer was washed with saturated brine
9. dry with materialdried (MgSO4)
10. concentrationconcentrated

ORD record

ord-eff547795e414cdd9b7878b9e4443ea7

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07241785B2