(R)-1-(1-phenylethyl)urea → (R)-1-(3-(ethylamino)-1-trityl-1H-pyrazolo[4,3-c]pyridin-6-yl)-3-(1-phenylethyl)urea

Participants

Reaction Conditions

Reaction Steps

6-Chloro-N-ethyl-1-trityl-1H-pyrazolo[4,3-c]pyridin-3-amine (3 g, 6.83 mmol), (R)-1-(1-phenylethyl)urea (1.68 g, 10.25 mmol), and BrettPhos pre-catalyst (546 mg, 0.68 mmol) were taken up in THF (13 mL). The resulting mixture was degassed for 5 min followed by addition of sodium tert-butoxide (6834 μL, 13.67 mmol) at room temperature. After the mixture was degassed again for 5 min, the reaction was heated to 50° C. under N2 for 6 h, Room temperature was attained, sat NH4Cl was added, and the mixture was extracted with EtOAc. The organic layer was washed with water, dried, filtered, and concentrated in vacuo. Purification of the residue by flash chromatography (0-100% EtOAc/Hexanes) gave (R)-1-(3-(ethylamino)-1-trityl-1H-pyrazolo[4,3-c]pyridin-6-yl)-3-(1-phenylethyl)urea. MS ESI calc'd. For C36H34N6O [M+1]+ 567. found 567.

Provenance & Evidence