Trifluoroacetic acid → 2-[4-(2-Aminoethyl)-phenoxy]-isonicotinonitrile

Participants

Reaction Steps

{2-[4-(4-Cyanopyridin-2-yloxy)-phenyl]-ethyl}-carbamic acid tert-butyl ester (5.57 g, 8.2 mmol) was dissolved with magnetic stirring in CH2Cl2 (100 mL) in a 250 mL round bottom flask equipped with a dry nitrogen line at 25° C. To this solution was added trifluoroacetic acid (10 mL), and the reaction mixture was kept at 25° C. for 3 h. The solution was concentrated in vacuo. The residue was taken up in H2O (50 mL) and EtOAc (75 mL) and treated with conc. ammonium hydroxide (NH4OH) to adjust the pH to 9-10. The layers were separated, and the aqueous fraction was extracted twice with EtOAc. The pooled organic fractions were filtered and concentrated in vacuo to afford 2-[4-(2-aminoethyl)-phenoxy]-isonicotinonitrile (3.52 g, 89%) as a beige waxy solid: 1H NMR (400 MHz, CDCl3) δ 8.32 (d, J=5.1 Hz, 1H), 7.27 (m, 2H), 7.19 (d, J=5.1 Hz, 1H), 7.15 (s, 1H), 7.07 (d, J=8.4 Hz, 2H), 3.00 (t, J=6.9 Hz, 2H), 2.78 (t, J=6.9 Hz, 2H), 1.63 (s, 2H); ESIMS m/z 240.1 ([M+H]+).

Provenance & Evidence