Dichloromethane → tert-butyl 4-(3-amino-6-(tetrahydro-2H-pyran-4-yl)pyrazin-2-yl)-2-fluorobenzoate

Participants

Reaction Steps

To a suspension of tert-butyl 4-(3-amino-6-(3,6-dihydro-2H-pyran-4-yl)pyrazin-2-yl)-2-fluorobenzoate (15 g, 40.4 mmol) in MeOH (800 mL) was added DCM (100 mL) until the suspension turned to a homogeneous solution. After degassed by N2 stream for 15 min, Pd/C (10 g, 9.40 mmol) was added to the reaction mixture. To this mixture, hydrogen balloon was equipped after flushed with hydrogen gas three times. The reaction mixture was stirred for 6 h. After the reaction mixture was filtered through Celite® pad, the volatile materials were removed in vacuo. The residue was dissolved in MeOH (200 mL) by heating and cooling down to room temperature and standing overnight. The brown precipitate was filtered off, which afforded 4.5 g of tert-butyl 4-(3-amino-6-(tetrahydro-2H-pyran-4-yl)pyrazin-2-yl)-2-fluorobenzoate. The filtrate was concentrated and dissolved in EtOH (200 mL) by heating. The second brown precipitate was filtered off to afford 3.9 g of tert-butyl 4-(3-amino-6-(tetrahydro-2H-pyran-4-yl)pyrazin-2-yl)-2-fluorobenzoate (55.7% combined yield). LCMS (m/z): 374.7 (MH+), 0.90 min.

Provenance & Evidence