HCID 69417566, compound → HCID 23235866, compound

Participants

Reaction Steps

A third intermediate compound, 1-(3-Fluoro-naphthalen-1-yl)-piperazine, was produced as follows: A solution of (3-fluoro-naphthalen-1-yl)-carbamic acid tert-butyl ester (4.78 g, 18.30 mmol) in dichloromethane (30 mL) and trifluoroacetic acid (10 mL) was refluxed for 2 hours. The mixture was diluted with diethyl ether and the solid that precipitated out was collected by vacuum filtration as the TFA salt (2.137 g). The filtrate was neutralized with 2N KOH and extracted with dichloromethane. The extracts were dried over anhydrous Na2SO4, filtered and concentrated to a brown residue. The residue was purified by column chromatography (5:1, hexanes/ethyl acetate) to afford 3-fluoro-naphthalen-1-ylamine (0.967 g, 33%). The TFA salt (2.137 g) was stirred in a heterogeneous solution of 2N KOH (10 mL) in dichloromethane (20 mL). The organic layer was separated and the aqueous layer was extracted with dichloromethane. The combined extracts were dried over anhydrous Na2SO4, filtered and concentrated to afford an additional amount of 3-fluoro-naphthalen-1-ylamine (1.193 g, 40%). 1H NMR (400 MHz, CDCl3) δ 7.78–7.64 (m, 2H), 7.48–7.42 (m, 1H), 7.41–7.34 (m, 1H), 6.90 (d, 1H), 6.54 (d, 1H), 4.30 (br s, 2H).

Provenance & Evidence