1,2-Dichloroethane → Tert-butyl 2-{[1-ethyl-4-(tetrahydro-2H-pyran-4-ylamino)-1H-pyrazolo[3,4-b]pyridin-5-yl]carbonyl}hydrazinecarboxylate

Participants

Reaction Steps

A suspension of Intermediate 17 (1.48 g), EDC (1.34 g) and HOBT (0.83 g) in DMF (20 ml) was stirred at room temperature for 30 min. t-Butyl carbazate (0.68 g) was then added and stirring continued under nitrogen for a further 66 h. The mixture was concentrated in vacuo and the residue divided into two portions for purification. Each portion was applied to an SPE cartridge (aminopropyl, 10 g) which was eluted with methanol and the combined eluents were concentrated in vacuo. Further purification was carried out by Biotage (silica, 40 g), eluting with cyclohexane:ethyl acetate (1:4). Fractions containing desired material were combined and concentrated in vacuo to afford Intermediate 18 (1.39 g). LCMS showed MH+=405; Tm=2.64 min.

Provenance & Evidence