Diisopropylethylamine → Ethyl 1-ethyl-6-methyl-4-(tetrahydro-2H-pyran-4-ylamino)-1H-pyrazolo[3,4-b]pyridine-5-carboxylate

Participants

Reaction Conditions

Reaction Steps

4-Aminotetrahydropyran hydrochloride (Intermediate 21, 0.413 g, 3.0 mmol) was added to a mixture of Intermediate 58 (0.268 g, 1.0 mmol) and N,N-diisopropylethylamine (0.87 ml, 5.0 mmol) in acetonitrile (3 ml). The resulting mixture was heated at 85° C. for 24 hours. Volatiles were removed in vacuo and the residue was dissolved in chloroform (1.5 ml) and applied to a SPE cartridge (silica, 5 g). The cartridge was eluted successively with Et2O, EtOAc and EtOAc-MeOH (9/1). Fractions containing the desired product were combined and concentrated in vacuo to give the desired product contaminated with starting material (Intermediate 51). Further purification using a SPE cartridge (silica, 5 g) eluting with ethyl acetate-cyclohexane (1:3) afforded Intermediate 59 (0.248 g). LCMS showed MH+=333; TRET=2.75 min.

Provenance & Evidence