Hydrochloric Acid → Methyl 1-[2-(4'-aminobiphenyl-4-yl)-2-oxoethyl]cyclopentanecarboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a 100 mL flask fitted with a reflux condenser was added methyl 1-[2-(4′-nitro-1,1′-biphenyl-4-yl)-2-oxoethyl]cyclopentanecarboxylate (1.68 g, 4.40 mmol) dissolved in 85% aqueous ethanol (55 mL), followed by addition of 2 N aqueous hydrochloric acid solution (2.20 mL) and finely powdered iron (0) (2.46 g, 44.1 mmol). The reaction mixture was heated to 85° C. over 2 h. Upon cooling, the darkly-colored reaction mixture was filtered under reduced pressure through 2 cm Celite®/2 cm silica, in order to remove iron particulates and polar impurities. The yellow filtrate was concentrated under reduced pressure, resulting in a solid that was triturated with 20 mL diethyl ether/20 mL hexane to afford methyl 1-[2-(4′-amino-1,1′-biphenyl-4-yl)-2-oxoethyl]cyclopentanecarboxylate as a light tan solid (1.20 g, 76%). LC-MS ret. time 2.71 min, m/z 338.1 (MH+); 1H NMR (300 MHz, CDCl3) δ 1.55-1.84 (overlapping signals, 6H), 2.25-2.35 (m, 2H), 3.44 (s, 2H), 3.67 (s, 3H), 7.40-8.10 (overlapping signals, 8H).

Herkunft & Nachweise