Triethylamine → 1-(2-(4-((3,4-dihydro-2H-pyrano(2,3-c)pyridin-6-ylmethyl)amino)piperidin-1-yl)ethyl)-7-fluoro-1,5-naphthyridin-2(1H)-one hydrochloride

Participants

Reaction Steps

A mixture of 1-[2-(4-amino-1-piperidinyl)ethyl]-7-fluoro-1,5-naphthyridin-2(1H)-one dihydrochloride (145 mg, 0.399 mmol) in chloroform (5 ml) and MeOH (0.1 ml) was treated with triethylamine (161 μl, 1.162 mmol) and stirred for 0.25 h before addition of 3,4-dihydro-2H-pyrano[2,3-c]pyridine-6-carbaldehyde (for a synthesis see WO2004058144, Example 126(e)) (59 mg, 0.363 mmol). The reaction was stirred for 0.5 h before addition of NaBH(OAc)3 (231 mg, 1.089 mmol). The reaction was stirred for 0.5 h before addition of sat. aq NaHCO3 (50 ml). The reaction was then extracted with 20% MeOH in DCM (3×200 ml). The combined organic phases were dried, evaporated and the crude residue purified by chromatography on silica gel using a 0-20% MeOH/DCM gradient to provide the free base of the title compound (132 mg, 76%).

Provenance & Evidence