Sodium triacetoxyborohydride → 7-{4-[4-(2-Trifluoromethyl-3H-benzoimidazol-4-yl)-piperazin-1-yl]-butoxy}-3,4-dihydro-1H-[1,8]naphthyridin-2-one

Participants

Reaction Steps

To a suspension of 4-(7-oxo-5,6,7,8-tetrahydro-[1,8]-naphthyridin-2-yloxy)-butyraldehyde (0.297 g, 1.266 mmol, 1.32 eq) and 4-piperazin-1-yl-2-trifluoromethyl-1H-benzoimidazole (0.258 g, 0.953 mmol, 1 eq) in dichloroethane (5 mL) was added NaBH(OAc)3 (0.723 g, 3.413 mmol, 3.58 eq). The slurry was allowed to stir overnight at room temperature (18 h). Analysis by HPLC showed reaction mostly complete. The mixture was diluted with Ethyl Acetate and quenched with saturated NaHCO3. The organic phase was then washed with brine, dried over Na2SO4, filtered and evaporated in vacuo. Purification by silica gel chromatography (2% MeOH/CH2Cl2) followed by formation of the HCl salt using 1N HCl in ether provided the title compound (0.166 g, 35%). MS: APCI: M+1: 489.2 (Exact Mass: 488.21).

Provenance & Evidence