Chloride → HCID 131728274, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 6-hydroxymethyl-benzo[b]thiophene-2-carboxylic acid ethyl ester (2.52 g, 10.7 mmol) and triethylamine (3.00 mL, 21.5 mmol) in anhydrous THF (80 mL) at 0° C. was added metahnesulfonyl chloride (1.24 mL, 16.0 mmol). The resulting mixture was allowed to stir at 0° C. for 30 min, diluted with EtOAc (400 mL), washed with saturated NaHCO3, water and brine. The organic layer was dried over Na2SO4. After filtration, the filtrate was concentrated and the residue was dissolved in anhydrous DMF (60 mL). After sodium azide (1.41 g, 21.6 mmol) was added, the mixture was heated at 50° C. for 30 min. After cooling to rt, the mixture was diluted with EtOAc (300 mL) and water (60 mL). The organic layer was further washed with water and brine, and then dried over Na2SO4. After filtration, the filtrate was concentrated and the residue was dissolved in THF (60 mL) and water (6 mL). Triphenylphosphine (3.64 g, 13.9 mmol) was added and the mixture was allowed to stir at rt overnight and then concentrated. The residue was dissolved in ether (400 mL) and 4M HCl in dioxane (6 mL) was added dropwise. The solid formed was washed with ether (5×30 mL) and dried to give 6-aminomethyl-benzo[b]thiophene-2-carboxylic acid ethyl ester, hydrochloride salt as a pale solid. 1H NMR (DMSO-d6, 200 MHz) δ 8.66 (brs, 2H), 8.24-8.10 (m, 2H), 8.06 (d, J=8.6 Hz, 1H), 7.62 (dd, J=8.4, 1.6 Hz, 1H), 4.34 (q, J=7.4 Hz, 2H), 4.13 (s, 2H), 1.32 (t, J=7.0 Hz, 3H). MS (EI): cal'd 236.1 (MH+), exp 236.1 (MH+).

Provenance & Evidence