Triethylamine → (2S)-2-(Hydroxymethyl)pyrrolidine-1-carbaldehyde

Participants

Reaction Steps

At a temperature of 0° C., a solution of 3-difluoromethyl-1-methyl-1H-pyrazole-4-carbonyl chloride (1.9 g, 10.0 mol) in dichloromethane (40 ml) was added dropwise to a stirred solution of (S)-pyrrolidin-2-yl-methanol (1.0 g, 10.0 mmol) and triethylamine (2.8 ml, 20.0 mmol) in dichloromethane 60 ml. The reaction mixture was stirred for 10 minutes at ambient temperature and then allowed to stand for 3 h at ambient temperature. The reaction mixture was washed with 1M NaOH (30 ml) and 2M HCl (30 ml) and then dried over Na2SO4. After removal of the solvent, the residue (1.76 g in the form of an oil) was purified by flash chromatography over silica gel (eluent:dichloromethane/methanol 9:1). 1.28 g (49% of theory) of (3-difluoromethyl-1-methyl-1H-pyrazol-4-yl)-((S)-(2-hydroxymethyl-pyrrolidin-1-yl)-methanone was obtained in form of an oil.

Provenance & Evidence