Hydrochloric Acid → Methyl 5-amino-1-benzothiophene-2-carboxylate

Participants

Reaction Steps

A suspension of 584 (3.52 g, 14.8 mmol) in methanol (100 ml) was treated with Fe powder (6.63 g, 118.7 mmol). The resulting suspension was heated to reflux, and 12M HCl (8.5 ml) was slowly added over 15 min. The resulting green dark suspension was refluxed for an additional 3 h, then cooled and concentrated. The residue was taken up in EtOAc and washed with saturated aqueous NaHCO3, then brine, dried over MgSO4, filtered and concentrated to afford (2.57 g, 84%). 1H NMR: (DMSO) δ (ppm): 7.92 (s, 1H), 7.65 (d, J=8.8 Hz, 1H), 7.05 (d, J=1.5 Hz, 1H), 6.88 (dd, J=1.8, 8.4 Hz, 1H), 5.27 (s, 2H), 3.85 (s, 3H). LRMS: 207.0 (Calc.). 208.1 (found).

Provenance & Evidence