Ammonium Chloride → tert-butyl 8-(4-aminophenylsulfonyl)-3,4-dihydrobenzofuro[3,2-c]pyridine-2(1H)-carboxylate

Participants

Reaction Steps

To a solution of product from step A (96 mg, 0.20 mmol) in ethanol (4.0 mL) and water (2.0 mL) was added iron powder (57 mg, 1.02 mmol) and ammonium chloride (12 mg, 0.22 mmol). After refluxing for 3 h, the reaction mixture was filtered through a bed of celite and the celite bed washed repeatedly with ethyl acetate. The filtrate was dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to give a crude product which was purified by flash column chromatography (SiO2, 3:2 hexanes/ethyl acetate) to give the product tert-butyl 8-(4-aminophenylsulfonyl)-3,4-dihydrobenzofuro[3,2-c]pyridine-2(1H)-carboxylate (76 mg, 87%) as an off-white solid: 1H NMR (CDCl3, 300 MHz) δ 8.22-8.19 (m, 1H), 7.88 (dd, J=8.7, 1.8 Hz, 1H), 7.81-7.75 (m, 2H), 7.67 (d, J=8.4 Hz, 1H), 6.97-6.91 (m, 2H), 4.48 (s, 2H), 3.54-3.52 (m, 2H), 3.23-3.16 (m, 2H), 1.55 (s, 9H).

Provenance & Evidence