tert-butyl 2-bromo-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylate

365996-05-0

365996-06-1

Method G - Step e: Synthesis of tert-butyl 2-bromo-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylate [0134] To a 100 mL DMF solution containing isoamyl nitrite (8.8 mL, 62.8 mmol) and copper(II) bromide (10.7 g, 48 mmol) was added tert-butyl 2-amino-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylate (10 g, 39.2 mmol) at 0°C. The reaction was carried out at 40°C and the reaction mixture was purified. The reaction mixture was stirred at 40°C for 30 min and then concentrated by evaporation. The concentrate was dissolved in 50 mL of water and extracted with dichloromethane (100 mL × 2). The organic phases were combined, washed with brine (30 mL × 2), and dried over anhydrous sodium sulfate. Purification by silica gel column chromatography (eluent: dichloromethane) afforded the target product tert-butyl 2-bromo-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylate (5.3 g, 42.4%) as a yellow solid.