反应详情

(S)-ethyl 6-bromo-1-(1-(tert-butoxycarbonyl)piperidin-3-yl)-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carboxylate (Intermediate 30, 10.847 g, 22.58 mmol) was taken up in dichloromethane (10 mL) and added HCl 4M in Dioxane (113 mL, 451.63 mmol) while stirring at RT for 1 h. The solvent was removed in vacuo and the residue was triturated with DCM, ether and EtOAc to give the desired product as a yellow solid. (S)-ethyl 6-bromo-4-oxo-1-(piperidin-3-yl)-1,4-dihydro-1,8-naphthyridine-3-carboxylate (8.50 g, 90%) was recovered as the HCl salt. MS (ES)(M+H)+: 381 for C16H18BrN3O3.[HCl].

1. customThe solvent was removed in vacuo
2. customthe residue was triturated with DCM, ether and EtOAc