tert-Butyl isocyanate → (R)-1-tert-butyl-3-(5-(2-(2,5-difluorophenyl)pyrrolidin-1-yl)pyrazolo[1,5-a]pyrimidin-3-yl)urea

Participants

Reaction Steps

To a DCM (0.8 mL) solution of (R)-5-(2-(2,5-difluorophenyl)pyrrolidin-1-yl)pyrazolo[1,5-a]pyrimidin-3-amine (Preparation B; 25 mg, 0.079 mmol) was added 2-isocyanato-2-methylpropane (9.4 mg, 0.095 mmol) at ambient temperature drop-wise, followed by addition of DIEA (0.028 mL, 0.16 mmol). The reaction was stirred for 4 hours then concentrated, and the residue was directly purified by reverse-phase column chromatography, eluting with 5 to 65% acetonitrile/water to yield the final product as a pale-yellowish solid (27 mg, 82% yield). MS (apci) m/z=415.1 (M+H).

Provenance & Evidence