Acetonitrile → HCID 178510444, compound

Participants

Reaction Steps

To a solution of dry acetonitrile (10 mL) and dry tetrahydrofuran (30 mL) was added 5-amino-1H-pyrazole-4-carbonitrile (1.0 g, 9.25 mmol) followed by triethylamine (1.08 mL, 1.74 mmol). The resulting suspension was allowed to stir at room temperature for five minutes and then cooled to 0° C. A solution of (bromomethanetriyl)tribenzene (1.89 g, 5.84 mmol) in dry tetrahydrofuran (10 mL) was added drop-wise via an addition funnel equipped with a nitrogen inlet, at such a rate that the temperature did not rise above 5° C. The addition funnel was then rinsed with dry tetrahydrofuran (5 mL) and the reaction mixture was stirred at 0° C. for 10 minutes, then allowed to warm to room temperature and stirred for 2 hours. The volatiles were removed in vacuo and residue was dissolved in EtOAc (150 mL) and washed once water (100 mL), once with saturated aqueous sodium chloride, dried over Na2SO4, filtered and concentrated in vacuo. The crude product was applied to an 80 g silica gel cartridge using methylene chloride, and the column was eluted with a 10-30% EtOAc/hexanes gradient. The product containing fractions were combined to give 3-(Trityl-amino)-1H-pyrazole-4-carbonitrile (1.3 g, 41%) as an off-white semi-crystalline solid.

Provenance & Evidence