Triethylamine → [1-(4-Chloromethyl-benzyl)-3,5-dimethyl-1H-pyrazol-4-yl]-acetic acid methyl ester

Participants

Reaction Steps

[1-(4-Hydroxymethyl-benzyl)-3,5-dimethyl-1H-pyrazol-4-yl]-acetic acid methyl ester (intermediate 16.1.1, 4.8 g, 16.7 mmol) was dissolved in 60 ml dichloromethane. Triethylamine (3.5 ml, 25 mmol) was added, followed by dropwise addition of methanesulfonyl chloride (1.29 ml, 16.7 mmol). After 12 h at room temperature, the mixture was washed with water, aqueous KHSO4 solution, water, aqueous NaHCO3 solution and with water. The organic layer was dried over MgSO4 and the solvent was evaporated under reduced pressure.

Provenance & Evidence