Trityl chloride → 1-Methyl-5-triphenylmethylaminopyrazole-4-carbaldehyde

Participants

Reaction Steps

To a suspension of 5-amino-1-methylpyrazole-4-carbaldehyde (25 g, 200 mmol) and triethylamine (22.2 g, 220 mmol) in dichloromethane (500 ml) was added triphenylmethyl chloride (61.3 g, 220 mmol) at room temperature. The mixture was stirred at room temperature for 70 hours. The reaction mixture was washed with successively 10% aqueous citric acid solution, brine and 10% aqueous sodium hydrogencarbonate solution. The extract was dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The residue was triturated with ethyl acetate to give 1-methyl-5-triphenylmethylaminopyrazole-4-carbaldehyde (67.6 g) as a colorless solid.

Provenance & Evidence