Diisopropylethylamine → (S)-4-(5-chloro-1-methyl-1H-pyrazolo[4,3-d]pyrimidin-7-yl)-3-methylmorpholine

Participants

Reaction Steps

To a stirred solution of 5,7-dichloro-1-methyl-1H-pyrazolo[4,3-d]pyrimidine (200.0 mg, 0.98 mmol) in anhydrous DMF (2 mL) was added N,N-diisopropylethylamine (0.21 mL, 1.18 mmol, 1.2 eq.) followed by (S)-3-methylmorpholine (199.3 mg, 1.9 mmol, 2.0 eq.). The reaction mixture was stirred at RT under N2 for 4 h and diluted with ether (50 mL). The organic layer was washed with saturated aqueous solution of sodium bicarbonate, water and brine, dried over Na2SO4, filtered, and concentrated in vacuo. The resultant residue was purified by column chromotagraphy (Si-PPC, gradient 0 to 100% ethyl acetate in heptane) to afford the desired product (k-1) as a foam (245.4 mg, 93.0%). 1H NMR (CDCl3, 500 MHz) δ ppm 8.03 (s, 1H), 4.21 (broad d, J=6.2 Hz, 1H), 4.15 (s, 3H), 3.97 (d, J=10.7 Hz, 1H), 3.90 (d, J=9.8 Hz, 1H), 3.81 to 3.65 (m, 3H), 3.56 (d, J=12.4 Hz, 1H), 1.38 (d, J=6.6 Hz, 3H); LC-MS m/z (method A)=268 [M+H]+, RT=1.71 min.

Provenance & Evidence