1320266-90-7

General procedure for the synthesis of 8-chloro-3-isopropylimidazo[1,5-a]pyrazine from the compound (CAS:1320266-89-4): POCl3 (0.08 mL, 0.90 mmol) was added to Intermediate I (37 mg, 0.18 mmol) dissolved in 0.78 mL acetonitrile. A drop of DMF was added as a catalyst and the reaction mixture was stirred at 55 °C for 30 min. Upon completion of the reaction, the mixture was concentrated under vacuum and the resulting solid was dissolved in a methanolic solution of 2 M ammonia, followed by another vacuum concentration. The solid obtained was dissolved in a minimal amount of water and the product was extracted with dichloromethane (4 times). The organic layers were combined, washed with saturated NaHCO3 solution (1 time), dried over Na2SO4 and concentrated in vacuum to give intermediate J (33 mg, 98% yield). The product was characterized by 1H-NMR (300 MHz, CDCl3): δ 1.46 (d, 6H, J = 6.9 Hz), 3.29-3.38 (m, 1H), 7.33 (d, 1H, J = 4.8 Hz), 7.61 (d, 1H, J = 5.1 Hz), 7.82 (s, 1H). The mass spectrum (ESI) showed (M + H)+ of 196.

[1] Patent: WO2011/94628, 2011, A1. Location in patent: Page/Page column 106
[2] Patent: WO2015/74138, 2015, A1. Location in patent: Page/Page column 38; 39